:root{font-family:PingFang SC,Noto Sans SC,Microsoft YaHei,system-ui,sans-serif;color:#1a2233;background:linear-gradient(180deg,#f6f8fb,#eef3f8);--panel: rgba(255, 255, 255, .9);--panel-strong: #ffffff;--line: rgba(26, 34, 51, .08);--line-strong: rgba(26, 34, 51, .14);--text: #1a2233;--muted: #6b7688;--blue: #1f67b2;--blue-soft: rgba(31, 103, 178, .12);--danger: #b5483f;--shadow: 0 18px 48px rgba(18, 28, 43, .08)}*{box-sizing:border-box}html,body,#root{margin:0;min-height:100%}body{min-height:100vh;color:var(--text)}button,input{font:inherit}.shell{display:grid;grid-template-columns:240px 1fr;min-height:100vh;transition:grid-template-columns .22s ease}.shell--sidebar-collapsed{grid-template-columns:88px 1fr}.sidebar{padding:28px 18px;border-right:1px solid rgba(26,34,51,.06);background:linear-gradient(180deg,#ffffffdb,#f6faffd6),radial-gradient(circle at top left,rgba(31,103,178,.1),transparent 34%);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);transition:padding .22s ease}.sidebar--collapsed{padding:28px 12px}.brand{display:flex;align-items:center;gap:12px;margin-bottom:24px;position:relative}.brand-copy{transition:opacity .14s ease}.brand-copy--hidden{opacity:0;pointer-events:none;width:0;overflow:hidden}.brand-mark{width:44px;height:44px;border-radius:14px;display:grid;place-items:center;background:linear-gradient(135deg,#0f4f95,#5c93cf);color:#fff;box-shadow:0 12px 24px #1f67b22e}.brand-kicker{margin:0;font-size:11px;color:var(--muted);letter-spacing:.08em;text-transform:uppercase}.brand h1{margin:2px 0 0;font-size:20px}.sidebar-toggle{margin-left:auto;width:32px;height:32px;border-radius:10px;border:1px solid rgba(26,34,51,.1);background:#fff;color:var(--muted);display:inline-flex;align-items:center;justify-content:center;cursor:pointer}.sidebar--collapsed .sidebar-toggle{margin-left:0}.nav{display:grid;gap:8px}.nav--secondary{margin-top:18px;padding-top:14px;border-top:1px solid rgba(26,34,51,.08)}.nav-section-title{margin:0;padding:0 12px;color:var(--muted);font-size:12px;letter-spacing:.08em;text-transform:uppercase}.nav-section-title--hidden{display:none}.nav-item{min-height:54px;border:0;border-radius:14px;background:transparent;display:flex;align-items:center;gap:12px;padding:0 14px;color:var(--text);cursor:pointer;transition:background .16s ease,color .16s ease}.sidebar--collapsed .nav-item{justify-content:center;padding:0}.nav-item-label--hidden{display:none}.nav-item--active{background:linear-gradient(135deg,#e3f0ff,#f5faff);color:var(--blue);font-weight:600;box-shadow:inset 0 0 0 1px #1f67b214}.main{padding:18px 22px}.topbar{display:flex;justify-content:flex-start;gap:8px;align-items:center;margin-bottom:6px}.topbar h2{margin:0;font-size:26px;letter-spacing:-.02em}.topbar-copy{display:grid;gap:4px}.context-row{display:flex;gap:6px;flex-wrap:wrap;margin-top:0}.context-row span,.chip-row span{min-height:28px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:var(--blue-soft);color:var(--blue);font-size:12px}.primary-btn,.ghost-btn{min-height:38px;border-radius:999px;display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:0 14px}.primary-btn{border:0;background:linear-gradient(135deg,#1d5da2,#4681c1);color:#fff;cursor:pointer}.ghost-btn{border:1px solid var(--line-strong);background:var(--panel-strong);color:var(--text);cursor:pointer}.ghost-btn--small{min-height:30px;padding:0 12px}.panel{border:1px solid var(--line);border-radius:28px;background:linear-gradient(180deg,#fffffff0,#fafcffeb);box-shadow:0 20px 52px #121f3114;padding:16px}.panel--full{grid-column:1 / -1}.section-head,.topic-top,.content-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.section-head h3{margin:0;font-size:19px}.content-label{display:inline-block;font-size:12px;color:var(--muted)}.chip-row{display:flex;gap:8px;flex-wrap:wrap;margin-top:8px}.page-grid,.assistant-layout,.library-shell{display:grid;gap:16px;margin-top:20px}.page-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.assistant-layout{grid-template-columns:minmax(0,1.4fr) 320px}.library-shell{grid-template-columns:300px 320px minmax(0,1fr)}.list,.mini-list,.topic-list,.settings-list,.message-list{display:grid;gap:12px;margin-top:16px}.list-item,.mini-card,.topic-card,.setting-row,.message{border-radius:16px;border:1px solid var(--line);background:var(--panel-strong);padding:16px}.list-item,.setting-row{display:flex;justify-content:space-between;gap:12px;align-items:center}.list-item strong,.topic-card strong{display:block}.list-item span,.setting-row span,.message span{color:var(--muted);font-size:13px}.topic-card p,.message p{margin:6px 0 0;color:var(--muted);line-height:1.65}.danger-text{color:var(--danger)}.message{max-width:82%}.message--assistant{background:#fff}.message--user{margin-left:auto;background:#dfeefe;border-color:#1f67b21f}.chat-input{display:grid;grid-template-columns:1fr auto;gap:10px;margin-top:16px}.chat-input input{min-height:44px;border-radius:14px;border:1px solid var(--line-strong);padding:0 14px;background:#fff}.lesson-plan-page{margin-top:20px}.lesson-plan-page--simple{display:grid;gap:18px}.lesson-plan-topbar{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;margin-bottom:18px}.lesson-plan-topbar h2{margin:8px 0 0;font-size:36px}.lesson-plan-intro{margin:12px 0 0;max-width:62ch;color:var(--muted);line-height:1.75}.lesson-config-strip{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.lesson-config-strip span{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.lesson-plan-top-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.lesson-save-status{min-width:120px;padding:10px 14px;border-radius:16px;border:1px solid var(--line);background:#fff}.lesson-save-status span,.lesson-save-status strong{display:block}.lesson-save-status span{color:var(--muted);font-size:12px}.lesson-save-status strong{margin-top:4px;font-size:14px}.lesson-workspace-topbar{display:flex;justify-content:space-between;gap:20px;align-items:flex-start}.lesson-workspace-topbar h2{margin:8px 0 0;font-size:32px}.lesson-workspace-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.lesson-workspace-layout{display:grid;grid-template-columns:220px minmax(0,1fr) 320px;gap:18px;align-items:start}.lesson-outline-panel,.lesson-support-panel{position:sticky;top:24px}.lesson-main-column{min-width:0}.lesson-edit-blocks{display:grid;gap:14px;margin-top:16px}.lesson-edit-card{padding:18px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff);cursor:pointer}.lesson-edit-card--active{border-color:#1f67b238;box-shadow:inset 0 0 0 1px #1f67b214}.lesson-edit-card-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.lesson-edit-card-head h4{margin:8px 0 0;font-size:22px}.lesson-block-tip{margin:10px 0 0;color:var(--muted);font-size:12px}.lesson-block-textarea{width:100%;min-height:140px;margin-top:12px;padding:14px 16px;border-radius:16px;border:1px solid var(--line-strong);background:#fff;color:var(--text);font:inherit;line-height:1.8;resize:vertical}.lesson-support-tabs{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;margin-top:14px}.lesson-support-tab{min-height:38px;border-radius:999px;border:1px solid var(--line);background:#fff;color:var(--muted);cursor:pointer}.lesson-support-tab--active{border-color:#1f67b233;background:#eef5fc;color:var(--blue)}.lesson-support-section{display:grid;gap:14px;margin-top:16px}.lesson-plan-shell{display:grid;grid-template-columns:260px minmax(0,1fr) 320px;gap:18px}.lesson-outline-list,.lesson-version-list,.lesson-meta-list,.lesson-ai-actions{display:grid;gap:10px;margin-top:16px}.lesson-outline-item{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff;text-align:left;cursor:pointer}.lesson-outline-item span,.lesson-outline-item strong{display:block}.lesson-outline-item span{color:var(--muted);font-size:12px}.lesson-outline-item strong{margin-top:6px}.lesson-outline-item--active{border-color:#1f67b233;background:#f6fbff;box-shadow:inset 0 0 0 1px #1f67b21a}.lesson-doc{display:grid;gap:16px;margin-top:18px}.lesson-doc-section{padding:20px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff);cursor:pointer}.lesson-doc-section h4,.lesson-doc-section p,.lesson-doc-section ul{margin:10px 0 0}.lesson-doc-top{display:flex;justify-content:space-between;gap:12px;align-items:center}.lesson-doc-section--active{border-color:#1f67b22e;box-shadow:inset 0 0 0 1px #1f67b214;background:linear-gradient(180deg,#f8fbff,#fff)}.lesson-doc-label{color:var(--blue);font-size:12px}.lesson-inline-ai{min-height:32px;padding:0 12px;border-radius:999px;border:1px solid rgba(31,103,178,.12);background:#eef5fc;color:var(--blue);cursor:pointer}.lesson-doc-section ul{padding-left:18px;color:var(--muted);line-height:1.8}.lesson-edit-panel{margin-top:18px;padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.lesson-edit-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.lesson-edit-head h4{margin:8px 0 0;font-size:20px}.lesson-edit-tip{min-height:34px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.lesson-editor-textarea{width:100%;min-height:240px;margin-top:16px;padding:16px 18px;border-radius:18px;border:1px solid var(--line-strong);background:#fff;color:var(--text);font:inherit;line-height:1.8;resize:vertical}.lesson-process-card{margin-top:12px;padding:16px;border-radius:18px;background:#f8fbff;border:1px solid rgba(31,103,178,.08)}.lesson-process-card strong{display:block}.lesson-process-card p{color:var(--muted);line-height:1.7}.lesson-process-list{display:grid;gap:12px;margin-top:12px}.lesson-side{display:grid;gap:18px}.lesson-ai-prompt{margin-top:16px;padding:16px;border-radius:18px;background:linear-gradient(180deg,#f8fbff,#fff);border:1px solid rgba(31,103,178,.08)}.lesson-ai-prompt p{margin:8px 0 0;color:var(--muted);line-height:1.7}.lesson-ai-chip{min-height:38px;padding:0 14px;border-radius:999px;border:1px solid rgba(31,103,178,.12);background:#eef5fc;color:var(--blue);text-align:left;cursor:pointer}.lesson-ai-input{display:grid;gap:12px;margin-top:16px}.lesson-ai-input textarea{min-height:120px;padding:14px;resize:none;border-radius:18px;border:1px solid var(--line-strong);background:#fff;color:var(--muted);line-height:1.7}.lesson-ai-result{margin-top:16px;padding:16px;border-radius:18px;border:1px solid rgba(31,103,178,.1);background:linear-gradient(180deg,#fff,#f8fbff)}.lesson-ai-result strong{display:block;margin-top:10px}.lesson-ai-result p{margin:10px 0 0;color:var(--muted);line-height:1.7}.lesson-ai-result-text{margin:12px 0 0;white-space:pre-wrap;word-break:break-word;font:inherit;color:var(--muted);line-height:1.75}.lesson-ai-result-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:14px}.lesson-meta-item,.lesson-version-item{padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff}.lesson-meta-item span,.lesson-version-item span{display:block;color:var(--muted);font-size:12px}.lesson-meta-item strong,.lesson-version-item strong{display:block;margin-top:6px;line-height:1.6}.lesson-version-item p{margin:8px 0 0;color:var(--muted);line-height:1.6}.lesson-alt-list{display:grid;gap:10px;margin-top:16px}.lesson-alt-item,.lesson-empty-box{padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff}.lesson-alt-top{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.lesson-alt-top span{color:var(--muted);font-size:12px}.lesson-alt-item p,.lesson-empty-box p{margin:8px 0 0;color:var(--muted);line-height:1.65}.lesson-alt-item .ghost-btn{margin-top:12px}.exercise-workspace-page{margin-top:20px}.exercise-topbar{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;margin-bottom:18px}.exercise-topbar h2{margin:8px 0 0;font-size:36px}.exercise-intro{margin:12px 0 0;max-width:64ch;color:var(--muted);line-height:1.75}.exercise-config-strip{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.exercise-config-strip span{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.exercise-top-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.exercise-save-status{min-width:120px;padding:10px 14px;border-radius:16px;border:1px solid var(--line);background:#fff}.exercise-save-status span,.exercise-save-status strong{display:block}.exercise-save-status span{color:var(--muted);font-size:12px}.exercise-save-status strong{margin-top:4px;font-size:14px}.exercise-workspace-shell{display:grid;grid-template-columns:260px minmax(0,1fr) 320px;gap:18px}.exercise-outline-list,.exercise-outline-items{display:grid;gap:10px}.exercise-outline-list{margin-top:16px}.exercise-outline-group{padding:14px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.exercise-outline-group-head{display:flex;justify-content:space-between;gap:12px;align-items:center}.exercise-outline-group-head span,.exercise-outline-group p{color:var(--muted);font-size:12px}.exercise-outline-group p{margin:8px 0 0;line-height:1.65}.exercise-outline-items{margin-top:12px}.exercise-outline-item{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff;text-align:left;cursor:pointer}.exercise-outline-item span,.exercise-outline-item strong{display:block}.exercise-outline-item span{color:var(--muted);font-size:12px}.exercise-outline-item strong{margin-top:6px;line-height:1.55}.exercise-outline-item--active{border-color:#1f67b233;background:#f6fbff;box-shadow:inset 0 0 0 1px #1f67b21a}.exercise-set-preview{display:grid;gap:16px;margin-top:18px}.exercise-group-head{display:flex;justify-content:space-between;gap:14px;align-items:flex-start}.exercise-group-head h4{margin:8px 0 0;font-size:24px}.exercise-group-head p{max-width:34ch;margin:0;color:var(--muted);line-height:1.7}.exercise-question-list{display:grid;gap:14px}.exercise-question-card{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff);cursor:pointer}.exercise-question-card--active{border-color:#1f67b22e;box-shadow:inset 0 0 0 1px #1f67b214;background:linear-gradient(180deg,#f8fbff,#fff)}.exercise-question-top{display:flex;justify-content:space-between;gap:12px;align-items:center}.exercise-question-top span{color:var(--blue);font-size:12px}.exercise-question-card strong{display:block;margin-top:12px;font-size:18px}.exercise-question-card p{margin:12px 0 0;color:var(--muted);line-height:1.75;white-space:pre-wrap}.exercise-edit-panel{margin-top:18px;padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.exercise-edit-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.exercise-edit-head h4{margin:8px 0 0;font-size:20px}.exercise-edit-tip{min-height:34px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.exercise-edit-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:14px;margin-top:16px}.exercise-edit-field{display:grid;gap:8px}.exercise-edit-field--full{grid-column:1 / -1}.exercise-edit-field span{color:var(--muted);font-size:13px}.exercise-input,.exercise-textarea{width:100%;border-radius:18px;border:1px solid var(--line-strong);background:#fff;color:var(--text);font:inherit}.exercise-input{min-height:46px;padding:0 14px}.exercise-textarea{min-height:170px;padding:14px 16px;line-height:1.75;resize:vertical}.exercise-textarea--large{min-height:210px}.exercise-side{display:grid;gap:18px}.exercise-alt-top{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.exercise-alt-top span{color:var(--muted);font-size:12px}.exercise-export-box{padding:16px;border-radius:18px;border:1px solid rgba(31,103,178,.1);background:linear-gradient(180deg,#fff,#f8fbff)}.exercise-export-box strong{display:block}.exercise-export-box p{margin:8px 0 0;color:var(--muted);line-height:1.7}.lesson-plan-intro,.exercise-intro,.ppt-intro,.board-intro{display:none}.ppt-page{margin-top:20px}.ppt-topbar{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;margin-bottom:18px}.ppt-topbar h2{margin:8px 0 0;font-size:36px}.ppt-intro{margin:12px 0 0;max-width:62ch;color:var(--muted);line-height:1.75}.ppt-config-strip{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.ppt-config-strip span{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.ppt-top-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.ppt-save-status{min-width:120px;padding:10px 14px;border-radius:16px;border:1px solid var(--line);background:#fff}.ppt-save-status span,.ppt-save-status strong{display:block}.ppt-save-status span{color:var(--muted);font-size:12px}.ppt-save-status strong{margin-top:4px;font-size:14px}.ppt-workspace-shell{display:grid;grid-template-columns:250px minmax(0,1fr) 320px;gap:18px}.ppt-outline-list{display:grid;gap:10px;margin-top:16px}.ppt-outline-item{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff;text-align:left;cursor:pointer}.ppt-outline-item span,.ppt-outline-item strong,.ppt-outline-item em{display:block}.ppt-outline-item span,.ppt-outline-item em{color:var(--muted);font-size:12px;font-style:normal}.ppt-outline-item strong{margin:6px 0}.ppt-outline-item--active{border-color:#1f67b233;background:#f6fbff;box-shadow:inset 0 0 0 1px #1f67b21a}.ppt-stage-preview{margin-top:18px}.ppt-slide-canvas{padding:24px;border-radius:26px;border:1px solid rgba(31,103,178,.1);background:radial-gradient(circle at top right,rgba(31,103,178,.08),transparent 28%),linear-gradient(180deg,#fff,#f8fbff);min-height:360px}.ppt-slide-top{display:flex;justify-content:space-between;gap:12px;align-items:center}.ppt-page-badge,.ppt-layout-tag{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;font-size:12px}.ppt-page-badge{background:#eaf4ff;color:var(--blue)}.ppt-layout-tag{background:#f3f6fb;color:var(--muted)}.ppt-slide-canvas h3{margin:20px 0 0;font-size:30px;line-height:1.3}.ppt-bullet-list{margin:18px 0 0;padding-left:20px;display:grid;gap:10px;color:var(--muted);line-height:1.75}.ppt-visual-box{margin-top:22px;padding:16px;border-radius:18px;background:#f8fbfff2;border:1px solid rgba(31,103,178,.08)}.ppt-visual-box strong{display:block}.ppt-visual-box p{margin:8px 0 0;color:var(--muted);line-height:1.65}.ppt-edit-panel{margin-top:18px;padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.ppt-edit-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.ppt-edit-head h4{margin:8px 0 0;font-size:20px}.ppt-edit-tip{min-height:34px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.ppt-edit-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:14px;margin-top:16px}.ppt-edit-field{display:grid;gap:8px}.ppt-edit-field span{color:var(--muted);font-size:13px}.ppt-edit-field input,.ppt-edit-field textarea{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line-strong);background:#fff;color:var(--text);font:inherit;line-height:1.7}.ppt-edit-field textarea{min-height:120px;resize:vertical}.ppt-bullets-textarea{min-height:220px}.ppt-side{display:grid;gap:18px}.ppt-ai-card{margin-top:12px;padding:14px 16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#fffffff5}.ppt-ai-card h4{margin:0;font-size:18px}.ppt-ai-card p{margin:12px 0 0;color:var(--muted);line-height:1.7}.ppt-preview-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:1200;background:#0a101bd1;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);display:grid;place-items:center;padding:24px}.ppt-preview-shell{width:min(1180px,100%);display:grid;gap:18px}.ppt-preview-topbar{display:flex;justify-content:space-between;gap:16px;align-items:flex-start;color:#fff}.ppt-preview-topbar h3{margin:8px 0 0;font-size:28px}.ppt-preview-stage{min-height:68vh;padding:30px;border-radius:32px;background:radial-gradient(circle at top left,rgba(108,159,255,.16),transparent 24%),linear-gradient(180deg,#fffffffa,#f6fafffa);box-shadow:0 24px 80px #00000047}.ppt-preview-slide{max-width:880px;margin:0 auto}.ppt-preview-slide h2{margin:24px 0 0;font-size:42px;line-height:1.25}.ppt-preview-controls{display:flex;justify-content:space-between;gap:16px;align-items:center}.ppt-preview-dots{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}.ppt-preview-dot{width:12px;height:12px;border-radius:999px;border:0;background:#ffffff3d;cursor:pointer}.ppt-preview-dot--active{width:30px;background:#fff}.export-format-list{display:grid;gap:10px}.export-format-card{width:100%;padding:16px;border-radius:18px;border:1px solid var(--line);background:#fff;text-align:left;cursor:pointer}.export-format-card strong{display:block}.export-format-card p{margin:8px 0 0;color:var(--muted);line-height:1.65}.export-format-card--active{border-color:#1f67b23d;background:#f6fbff;box-shadow:inset 0 0 0 1px #1f67b21a}.export-success-box{padding:16px;border-radius:18px;border:1px solid rgba(31,103,178,.12);background:linear-gradient(180deg,#f8fbff,#fff)}.export-success-box strong{display:block}.export-success-box p{margin:8px 0 0;color:var(--muted);line-height:1.7}.board-page{margin-top:20px}.board-topbar{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;margin-bottom:18px}.board-topbar h2{margin:8px 0 0;font-size:36px}.board-intro{margin:12px 0 0;max-width:62ch;color:var(--muted);line-height:1.75}.board-config-strip{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.board-config-strip span{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.board-top-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.board-save-status{min-width:120px;padding:10px 14px;border-radius:16px;border:1px solid var(--line);background:#fff}.board-save-status span,.board-save-status strong{display:block}.board-save-status span{color:var(--muted);font-size:12px}.board-save-status strong{margin-top:4px;font-size:14px}.board-workspace-shell{display:grid;grid-template-columns:240px minmax(0,1fr) 320px;gap:18px}.board-outline-list{display:grid;gap:10px;margin-top:16px}.board-outline-item{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff;text-align:left;cursor:pointer}.board-outline-item span,.board-outline-item strong{display:block}.board-outline-item span{color:var(--muted);font-size:12px}.board-outline-item strong{margin-top:6px}.board-outline-item--active{border-color:#1f67b233;background:#f6fbff;box-shadow:inset 0 0 0 1px #1f67b21a}.board-stage-preview{margin-top:18px}.board-canvas{padding:24px;border-radius:28px;border:1px solid rgba(31,103,178,.08);background:linear-gradient(transparent 31px,#1f67b20a 32px),linear-gradient(90deg,transparent 31px,rgba(31,103,178,.03) 32px),linear-gradient(180deg,#fffef9,#fdfcf5);background-size:32px 32px,32px 32px,100% 100%}.board-header h3{margin:0;font-size:30px}.board-header p{margin:8px 0 0;color:var(--muted)}.board-column-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:24px}.board-column-card{min-height:220px;padding:18px;border-radius:20px;border:1px dashed rgba(31,103,178,.18);background:#ffffffc2;cursor:pointer}.board-column-card strong{display:block;font-size:18px}.board-column-card ul{margin:14px 0 0;padding-left:18px;display:grid;gap:10px;color:var(--muted);line-height:1.7}.board-column-card--active{border-style:solid;border-color:#1f67b238;background:#f4f9ffeb}.board-summary-box{margin-top:18px;padding:16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#ffffffe6}.board-summary-box strong{display:block}.board-summary-box p{margin:8px 0 0;color:var(--muted);line-height:1.7}.board-edit-panel{margin-top:18px;padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.board-edit-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.board-edit-head h4{margin:8px 0 0;font-size:20px}.board-edit-tip{min-height:34px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.board-edit-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:16px}.board-edit-field{display:grid;gap:8px}.board-edit-field span{color:var(--muted);font-size:13px}.board-edit-field input,.board-edit-field textarea{width:100%;padding:14px 16px;border-radius:18px;border:1px solid var(--line-strong);background:#fff;color:var(--text);font:inherit;line-height:1.7}.board-edit-field textarea{min-height:160px;resize:vertical}.board-side{display:grid;gap:18px}.board-ai-card{margin-top:12px;padding:14px 16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#fffffff5}.board-ai-card h4{margin:0;font-size:18px}.board-ai-list{margin:12px 0 0;padding-left:18px;display:grid;gap:8px;color:var(--muted);line-height:1.7}.board-ai-card p{margin:12px 0 0;color:var(--muted);line-height:1.7}.prep-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.prep-quick-entry{display:grid;gap:14px}.prep-entry-form{display:grid;grid-template-columns:minmax(0,1.4fr) 180px auto;gap:10px}.prep-entry-form input,.prep-entry-form select{min-height:42px;border-radius:12px;border:1px solid var(--line-strong);padding:0 12px;background:#fff}.prep-topic-chip-row span{min-height:30px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eaf4ff;color:var(--blue);font-size:12px}.topics-grid{grid-template-columns:1.25fr .75fr}.topics-category-row{margin-top:12px;display:flex;flex-wrap:wrap;gap:8px}.topic-filter-chip{min-height:34px;padding:0 12px;border-radius:999px;border:1px solid var(--line);background:#fff;color:var(--text);cursor:pointer}.topic-filter-chip--active{border-color:#1f67b23d;background:#eaf4ff;color:var(--blue)}.topic-card--briefing{background:linear-gradient(180deg,#fff,#f7fbff)}.topic-subscribe-panel{display:grid;gap:12px;margin-top:14px}.topic-list--detailed{grid-template-columns:repeat(2,minmax(0,1fr))}.topic-card--detailed{padding:18px;border-radius:20px}.topic-card-actions{display:flex;flex-wrap:wrap;gap:8px}.topic-teaching-grid{margin-top:12px;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.topic-teaching-card{padding:12px;border-radius:14px;border:1px solid var(--line);background:#fff}.topic-teaching-card span{display:block;color:var(--blue);font-size:12px}.topic-teaching-card p{margin:8px 0 0;color:var(--muted);line-height:1.6}.materials-grid{grid-template-columns:300px minmax(0,1fr)}.prep-entry-page{grid-template-columns:minmax(0,1fr)}.prep-entry-hero{display:grid;gap:16px;padding:28px;background:radial-gradient(circle at top right,rgba(79,142,204,.12),transparent 28%),linear-gradient(180deg,#fbfdff,#fff)}.prep-entry-copy{max-width:640px}.prep-entry-kicker{min-height:28px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.prep-entry-copy h3{margin:12px 0 0;font-size:36px;line-height:1.08}.prep-entry-copy p{margin:12px 0 0;color:var(--muted);line-height:1.8}.prep-entry-books{display:grid;gap:14px}.prep-entry-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.prep-entry-book{border:1px solid var(--line);border-radius:26px;background:linear-gradient(180deg,#fffffffa,#f7faffeb);padding:16px;text-align:left;cursor:pointer;display:grid;gap:16px;box-shadow:0 18px 32px #182a4414;transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease}.prep-entry-book:hover{transform:translateY(-2px);border-color:#1f67b22e;box-shadow:0 22px 38px #182a441f}.prep-entry-book-cover{min-height:240px;border-radius:22px;padding:18px;display:flex;flex-direction:column;justify-content:space-between;color:#fff}.prep-entry-book-cover span,.prep-entry-book-cover strong,.prep-entry-book-cover em{display:block}.prep-entry-book-cover span{width:fit-content;min-height:28px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#ffffff29;font-size:12px}.prep-entry-book-cover strong{margin-top:auto;font-size:32px;line-height:1.08}.prep-entry-book-cover em{margin-top:14px;font-style:normal;color:#ffffffe6}.prep-entry-book-meta strong,.prep-entry-book-meta p,.prep-entry-book-meta span{display:block}.prep-entry-book-meta strong{font-size:18px}.prep-entry-book-meta p{margin:8px 0 0;color:var(--muted)}.prep-entry-book-meta span{margin-top:14px;color:var(--blue);font-size:13px;font-weight:600}.prep-simple-grid{grid-template-columns:minmax(0,1fr)}.prep-simple-hero{display:grid;gap:18px}.prep-simple-selector{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.prep-book-tile{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);text-align:left;cursor:pointer;transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease}.prep-book-tile:hover{transform:translateY(-2px);border-color:#1f67b233;box-shadow:0 12px 30px #1c3f6914}.prep-book-tile strong,.prep-book-tile span,.prep-book-tile em{display:block}.prep-book-tile strong{font-size:18px}.prep-book-tile span{margin-top:8px;color:var(--muted)}.prep-book-tile em{margin-top:18px;color:var(--blue);font-style:normal;font-size:12px}.prep-simple-actions{display:flex;justify-content:flex-start}.prep-topic-chip-row{display:flex;flex-wrap:wrap;gap:8px}.prep-topic-chip-row span{min-height:32px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.materials-page-simple,.materials-by-book-page{grid-template-columns:280px minmax(0,1fr)}.materials-hero{display:grid;gap:16px}.materials-recommend-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:14px}.materials-recommend-card{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);display:grid;gap:12px}.materials-card-top{display:flex;justify-content:space-between;gap:10px;align-items:center}.materials-type-badge{min-height:28px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.materials-recommend-card strong{font-size:18px}.materials-recommend-card p{margin:0;color:var(--muted);line-height:1.7}.materials-card-actions{display:flex;gap:10px;margin-top:4px}.materials-quick-filter-panel,.materials-book-shelf-panel{align-self:start}.materials-book-shelf{display:grid;gap:12px;margin-top:14px}.materials-book-card{padding:16px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);text-align:left;cursor:pointer}.materials-book-card strong,.materials-book-card span,.materials-book-card em{display:block}.materials-book-card span{margin-top:8px;color:var(--muted)}.materials-book-card em{margin-top:14px;color:var(--blue);font-style:normal;font-size:12px}.materials-book-card--active{border-color:#1f67b238;box-shadow:inset 0 0 0 1px #1f67b214}.materials-book-detail-panel{min-width:0}.materials-book-summary{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-top:14px}.materials-book-summary-card{padding:16px;border-radius:18px;border:1px solid var(--line);background:#fff}.materials-book-summary-card span,.materials-book-summary-card strong{display:block}.materials-book-summary-card span{color:var(--muted);font-size:12px}.materials-book-summary-card strong{margin-top:8px;font-size:18px}.materials-bundle-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:14px}.materials-bundle-card{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);display:grid;gap:12px}.materials-bundle-card strong{font-size:18px}.materials-bundle-card p{margin:0;color:var(--muted);line-height:1.7}.materials-bundle-meta{color:var(--muted);font-size:12px}.materials-bundle-preview{padding:14px;border-radius:16px;border:1px solid rgba(31,103,178,.08);background:#fff}.materials-bundle-preview span,.materials-bundle-preview strong{display:block}.materials-bundle-preview span{color:var(--blue);font-size:12px}.materials-bundle-preview strong,.materials-bundle-preview p{margin-top:8px}.materials-bundle-foot{display:flex;justify-content:space-between;gap:10px;align-items:center}.materials-bundle-foot span{color:var(--muted);font-size:12px}.materials-inline-list{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin-top:14px}.plans-by-book-page{grid-template-columns:280px minmax(0,1fr)}.plans-book-shelf-panel{align-self:start}.plans-book-detail-panel{min-width:0}.plans-chapter-list{display:grid;gap:14px;margin-top:14px}.plans-chapter-card{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);display:grid;gap:12px}.plans-chapter-top{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.plans-chapter-top strong{display:block;font-size:18px}.plans-chapter-top p{margin:8px 0 0;color:var(--muted)}.plans-artifact-row{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.plans-artifact-chip{padding:12px;border-radius:16px;border:1px solid rgba(31,103,178,.08);background:#fff}.plans-artifact-chip strong,.plans-artifact-chip span{display:block}.plans-artifact-chip span{margin-top:6px;color:var(--muted);font-size:12px}.materials-search-row{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:10px}.materials-search-row input{min-height:42px;border-radius:12px;border:1px solid var(--line-strong);padding:0 12px;background:#fff}.materials-filter-panel{align-self:start}.materials-list-panel{min-width:0}.topic-card--compact{padding:14px;border-radius:16px}.topic-list--asset-pack{grid-template-columns:repeat(3,minmax(0,1fr))}.plans-grid,.dashboard-grid,.settings-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.progress-track{width:140px;height:8px;border-radius:999px;background:#e8eff8;overflow:hidden}.progress-bar{height:100%;border-radius:inherit;background:linear-gradient(90deg,#1d5da2,#67a9e7)}.lesson-hotspot-list{display:grid;gap:10px;margin-top:12px}.lesson-hotspot-item{padding:14px 16px;border-radius:18px;border:1px solid var(--line);background:#fff}.lesson-hotspot-item strong{display:block}.lesson-hotspot-item p{margin:8px 0 0;color:var(--muted);line-height:1.65}.hotspot-reference-list{display:grid;gap:10px;margin-top:12px}.hotspot-reference-card{padding:14px 16px;border-radius:16px;border:1px solid var(--line);background:#fff}.hotspot-reference-card strong,.hotspot-reference-card span{display:block}.hotspot-reference-card span{margin-top:6px;color:var(--blue);font-size:12px}.hotspot-reference-card p{margin:8px 0 0;color:var(--muted);line-height:1.65}.hotspot-mark{padding:0 6px;border-radius:6px;background:#fff3bf;color:#6a4c00}.library-home{margin-top:20px}.library-hero{display:grid;grid-template-columns:minmax(0,1.5fr) 360px;gap:18px;margin-bottom:18px}.library-hero-copy,.library-hero-metrics{border-radius:30px;padding:28px;border:1px solid rgba(31,103,178,.08);box-shadow:0 20px 50px #121f3114}.library-hero-copy{background:radial-gradient(circle at top right,rgba(106,167,230,.18),transparent 32%),linear-gradient(135deg,#0e417f,#1d5da2 52%,#4f8ecc);color:#fff}.library-eyebrow{margin:0 0 10px;font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:#ffffffc2}.library-hero-copy h3{margin:0;max-width:14ch;font-size:38px;line-height:1.05}.library-hero-copy p:last-child{margin:18px 0 0;max-width:58ch;line-height:1.8;color:#ffffffd6}.library-hero-metrics{display:grid;gap:12px;background:linear-gradient(180deg,#fffffff5,#f4f8fdeb)}.hero-metric-card{padding:18px;border-radius:20px;background:#fff;border:1px solid rgba(26,34,51,.06)}.hero-metric-card strong,.hero-metric-card span{display:block}.hero-metric-card strong{font-size:34px;color:var(--blue)}.hero-metric-card span{margin-top:6px;color:var(--muted);font-size:13px}.book-shelf{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:20px;margin-top:18px}.shelf-card{display:grid;gap:16px;padding:16px;border-radius:26px;border:1px solid var(--line);background:linear-gradient(180deg,#fffffffa,#f7faffeb);box-shadow:0 22px 42px #182a441a}.book-cover{position:relative;min-height:312px;padding:22px 20px 18px;border-radius:24px;overflow:hidden;display:flex;flex-direction:column;justify-content:space-between;color:#fff;box-shadow:inset 0 1px #ffffff2e}.book-cover:before{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(circle at top right,rgba(255,255,255,.24),transparent 34%),linear-gradient(180deg,rgba(255,255,255,.08),transparent 48%);pointer-events:none}.book-cover:after{content:"";position:absolute;top:14px;bottom:14px;left:12px;width:8px;border-radius:999px;background:#fff3;box-shadow:inset -2px 0 4px #0000001f}.book-cover span,.book-cover strong,.book-cover em{position:relative;z-index:1}.book-cover span{display:inline-flex;align-items:center;min-height:30px;width:fit-content;padding:0 10px;border-radius:999px;background:#ffffff29;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);font-size:12px;letter-spacing:.04em}.book-cover strong{margin-top:auto;padding-left:16px;font-size:34px;line-height:1.08;letter-spacing:.02em}.book-cover em{margin-top:14px;padding-left:16px;font-style:normal;font-size:15px;color:#ffffffe6}.cover-blue{background:linear-gradient(160deg,#0f4f95,#1f67b2 44%,#67a9e7)}.cover-navy{background:linear-gradient(160deg,#1f2f54,#2d4b81 46%,#7da3d8)}.cover-cyan{background:linear-gradient(160deg,#006276,#0688a1 48%,#7bd1dd)}.shelf-meta{display:grid;gap:8px}.shelf-meta h4{margin:0;font-size:30px;line-height:1.15}.shelf-meta p{margin:0;color:var(--muted);font-size:15px}.shelf-meta p{display:none}.shelf-meta .primary-btn{justify-self:flex-start;margin-top:8px}.shelf-tags{display:flex;gap:8px;flex-wrap:wrap}.shelf-tags span,.section-subcopy{color:var(--muted)}.shelf-tags span{min-height:30px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;font-size:12px}.section-subcopy{margin:8px 0 0;font-size:14px}.reader-shell{display:grid;grid-template-columns:280px minmax(0,1fr);gap:18px;margin-top:14px}.reader-menu,.reader-content{min-height:720px}.back-link{display:inline-flex;align-items:center;gap:6px;padding:0;border:0;background:transparent;color:var(--blue);cursor:pointer}.reader-book{display:grid;gap:6px;margin-top:14px;padding:14px;border-radius:24px}.reader-book strong{font-size:24px}.reader-book span,.reader-book em{color:#ffffffe0;font-size:14px}.reader-book--cover{position:relative;overflow:hidden;color:#fff;box-shadow:0 18px 34px #121f312e}.reader-book--cover:before{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(circle at top right,rgba(255,255,255,.24),transparent 30%),linear-gradient(180deg,rgba(255,255,255,.08),transparent 45%)}.reader-book--cover strong,.reader-book--cover span,.reader-book--cover em{position:relative;z-index:1}.reader-book-badge{width:fit-content;min-height:30px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#ffffff29}.reader-book em{font-style:normal}.reader-menu-group{margin-top:14px}.reader-menu-group--compact{margin-top:16px}.reader-menu-label{margin:0 0 12px;color:var(--muted);font-size:12px;letter-spacing:.08em;text-transform:uppercase}.reader-task-card{padding:16px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);display:grid;gap:10px}.reader-task-card strong{display:block;font-size:17px}.reader-task-card p{margin:0;color:var(--muted);line-height:1.7}.reader-task-card .ghost-btn{justify-self:flex-start}.reader-nav,.catalog-list,.reader-list,.image-grid{display:grid;gap:12px;margin-top:14px}.reader-nav-item,.catalog-item{width:100%;text-align:left;border:1px solid var(--line);background:var(--panel-strong);border-radius:16px;padding:12px 14px;cursor:pointer}.reader-nav-item{display:flex;align-items:center;gap:10px}.reader-nav-item--active,.catalog-item--active{border-color:#1f67b23d;box-shadow:inset 0 0 0 1px #1f67b21f;background:#f7fbff;color:var(--blue)}.catalog-item span{display:block;font-size:12px;color:var(--blue)}.catalog-item strong,.reader-card strong,.image-card strong{display:block}.catalog-item strong{margin-top:4px;font-size:15px;color:var(--text)}.catalog-item p,.reader-card p{margin:8px 0 0;color:var(--muted);line-height:1.7}.catalog-workspace{display:grid;grid-template-columns:300px minmax(0,1fr);gap:16px;min-height:100%}.catalog-column,.chapter-stage{min-width:0}.catalog-tree{display:grid;gap:14px;margin-top:14px}.catalog-group{padding:14px;border-radius:24px;border:1px solid var(--line);background:linear-gradient(180deg,#f8fbff,#fff)}.catalog-panel-head p{margin:8px 0 0;color:var(--muted);line-height:1.7}.catalog-group-head{display:flex;justify-content:space-between;gap:12px;align-items:center;padding-bottom:8px;margin-bottom:8px;border-bottom:1px solid rgba(26,34,51,.08)}.catalog-group-head span{font-weight:700;color:var(--text)}.catalog-group-head em{font-style:normal;color:var(--muted);font-size:12px}.catalog-list--compact{margin-top:0}.catalog-inline-link{margin-top:8px;color:var(--blue);font-size:12px;font-weight:600}.chapter-stage{display:grid;align-content:start;gap:12px}.chapter-stage-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start;padding:18px;border-radius:26px;border:1px solid var(--line);background:radial-gradient(circle at top right,rgba(79,142,204,.12),transparent 28%),linear-gradient(180deg,#fbfdff,#fff)}.chapter-stage-head h3{margin:4px 0 6px;font-size:26px;line-height:1.08}.chapter-stage-head p{margin:0;color:var(--muted);line-height:1.7}.chapter-head-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px}.chapter-head-actions .ghost-btn,.chapter-head-actions .primary-btn{white-space:nowrap}.chapter-stage-meta{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}.chapter-stage-meta span{min-height:26px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:11px}.chapter-context-strip{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}.chapter-context-strip span{min-height:30px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.chapter-status-strip{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.status-tile{padding:12px 14px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:linear-gradient(180deg,#fff,#f8fbff)}.status-tile strong,.status-tile span{display:block}.status-tile span{margin-top:4px;color:var(--muted);font-size:12px;line-height:1.45}.chapter-entry-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.chapter-entry-card{padding:16px;border-radius:20px;text-align:left;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#f8fbff);cursor:pointer;box-shadow:0 12px 24px #111c2b0a}.chapter-entry-card strong,.chapter-entry-card span{display:block}.chapter-entry-card strong{font-size:16px}.chapter-entry-card span{margin-top:6px;font-size:12px;color:var(--muted)}.chapter-entry-card--active{border-color:#1f67b23d;background:linear-gradient(180deg,#edf6ff,#fff);box-shadow:inset 0 0 0 1px #1f67b21f}.chapter-toolbar{display:flex;gap:8px;flex-wrap:wrap}.chapter-toolbar--wide .chapter-tool{min-width:108px;justify-content:center}.chapter-tool{min-height:34px;border-radius:999px;border:1px solid var(--line);background:var(--panel-strong);padding:0 12px;display:inline-flex;align-items:center;gap:8px;cursor:pointer;font-size:12px}.chapter-tool--active{border-color:#1f67b23d;background:#eaf4ff;color:var(--blue);box-shadow:inset 0 0 0 1px #1f67b21f}.chapter-stage-body{min-width:0}.chapter-preview{display:grid;gap:12px}.book-tools-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:72;background:#0e141f61;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);display:flex;justify-content:flex-end}.book-tools-drawer{width:min(1180px,96vw);height:100%;background:#f4f8fd;border-left:1px solid rgba(26,34,51,.08);box-shadow:-22px 0 42px #0c141f33;display:flex;flex-direction:column}.book-tools-head{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;padding:20px 22px 16px;border-bottom:1px solid rgba(26,34,51,.08);background:#ffffffc7}.book-tools-head strong{display:block;font-size:20px}.book-tools-head p{margin:8px 0 0;color:var(--muted);line-height:1.7}.book-tools-shell{display:grid;grid-template-columns:260px minmax(0,1fr);gap:18px;min-height:0;flex:1;padding:18px 22px 22px}.book-tools-nav{display:grid;align-content:start;gap:10px}.book-tools-content{min-width:0;overflow:auto}.chapter-summary-card--compact .chip-row{margin-top:10px}.chapter-summary-top{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.chapter-main-card{display:grid;gap:16px;padding:20px;background:radial-gradient(circle at top right,rgba(79,142,204,.1),transparent 30%),linear-gradient(180deg,#fbfdff,#fff)}.chapter-main-card-top{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(260px,.9fr);gap:16px;align-items:start}.chapter-main-copy h4{margin:8px 0 0;font-size:28px;line-height:1.08}.chapter-main-copy p{margin:10px 0 0;color:var(--muted);line-height:1.75}.chapter-main-side{padding:16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#ffffffd6}.chapter-main-side strong{display:block}.chapter-main-side p{margin:8px 0 0;color:var(--muted);line-height:1.7}.chapter-main-actions{display:flex;flex-wrap:wrap;gap:10px}.chapter-material-notice{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:14px 16px;border-radius:18px;border:1px solid rgba(31,103,178,.1);background:#ffffffe0}.chapter-material-notice strong,.chapter-material-notice span{display:block}.chapter-material-notice strong{font-size:14px}.chapter-material-notice span{color:var(--blue);font-size:13px;text-align:right}.chapter-detail-entry{display:flex;justify-content:space-between;gap:14px;align-items:center}.chapter-detail-entry p{margin:8px 0 0;color:var(--muted);line-height:1.65}.chapter-detail-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:70;background:#0e141f5c;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);display:flex;justify-content:flex-end}.chapter-detail-drawer{width:min(980px,96vw);height:100%;background:#f4f8fd;border-left:1px solid rgba(26,34,51,.08);box-shadow:-22px 0 42px #0c141f33;display:flex;flex-direction:column;animation:chapterDrawerIn .22s ease}@keyframes chapterDrawerIn{0%{transform:translate(18px);opacity:.72}to{transform:translate(0);opacity:1}}.chapter-detail-drawer-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;padding:18px 20px;border-bottom:1px solid rgba(26,34,51,.08);background:#fff}.chapter-detail-drawer-head p{margin:8px 0 0;color:var(--muted)}.chapter-detail-drawer-body{flex:1;overflow-y:auto;padding:16px 18px 24px;display:grid;gap:12px}.chapter-info-strip{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:12px}.chapter-center-head{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.chapter-center-head p{margin:8px 0 0;color:var(--muted);line-height:1.7}.chapter-ability-row{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px}.chapter-resource-grid,.qa-card-list,.topic-hook-grid,.mapping-grid{display:grid;gap:12px;margin-top:12px}.chapter-resource-grid,.chapter-resource-grid--wide{grid-template-columns:repeat(3,minmax(0,1fr))}.chapter-resource-card,.qa-card,.topic-hook-card,.mapping-card{padding:16px 18px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.chapter-resource-card--button,.qa-question-item{width:100%;text-align:left;cursor:pointer}.chapter-resource-card--button{transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease}.chapter-resource-card--button:hover{transform:translateY(-2px);border-color:#1f67b233;box-shadow:0 12px 24px #15223414}.chapter-resource-card strong,.chapter-resource-card span,.topic-hook-card strong,.topic-hook-card span,.mapping-card strong{display:block}.chapter-resource-card span{margin-top:8px;color:var(--muted);font-size:13px}.qa-card-head,.topic-hook-top{display:flex;justify-content:space-between;gap:12px;align-items:center}.qa-card-head span,.topic-hook-top span{color:var(--blue);font-size:12px}.qa-card h5{margin:12px 0 0;font-size:18px;line-height:1.5}.qa-card p,.topic-hook-card p{margin:10px 0 0;color:var(--muted);line-height:1.75}.qa-interaction-grid{display:grid;grid-template-columns:320px minmax(0,1fr);gap:14px;margin-top:16px}.qa-question-list,.citation-detail-list,.mapping-detail-list{display:grid;gap:12px}.qa-question-item{padding:16px 18px;border-radius:18px;border:1px solid var(--line);background:#fff}.qa-question-item span,.qa-question-item strong{display:block}.qa-question-item span{color:var(--muted);font-size:12px}.qa-question-item strong{margin-top:8px;line-height:1.6}.qa-question-item--active{border-color:#1f67b23d;background:#f7fbff;box-shadow:inset 0 0 0 1px #1f67b21f}.qa-answer-panel{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.qa-answer-panel h5{margin:14px 0 0;font-size:22px;line-height:1.45}.qa-answer-panel p{margin:12px 0 0;color:var(--muted);line-height:1.8}.citation-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}.citation-row span{min-height:28px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;background:#eef5fc;color:var(--blue);font-size:12px}.citation-detail-card,.mapping-detail-card{padding:14px 16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#fffffff5}.citation-detail-card strong,.mapping-detail-card span,.mapping-detail-card h5{display:block}.citation-detail-card strong,.mapping-detail-card span{color:var(--blue);font-size:12px}.citation-detail-card p,.mapping-detail-card p{margin:8px 0 0;color:var(--muted);line-height:1.75}.mapping-detail-card h5{margin:8px 0 0;font-size:16px;line-height:1.55;color:var(--text)}.topic-hook-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.mapping-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.mapping-card .chip-row,.topic-hook-card .chip-row{margin-top:14px}.chapter-summary-card{background:linear-gradient(180deg,#fff,#fbfdff)}.summary-grid,.chapter-overview-grid{display:grid;gap:14px}.summary-grid,.chapter-overview-grid,.ebook-meta-strip{grid-template-columns:repeat(2,minmax(0,1fr))}.outline-list{display:grid;gap:10px;margin-top:12px}.quick-link-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}.outline-action{position:relative;padding:0 0 0 14px;border:0;background:transparent;text-align:left;color:var(--muted);line-height:1.7;cursor:pointer}.outline-action:before{content:"";position:absolute;top:10px;left:0;width:6px;height:6px;border-radius:999px;background:var(--blue)}.outline-action:hover{color:var(--blue)}.ebook{margin-top:18px;padding:28px;border-radius:20px;border:1px solid var(--line);background:linear-gradient(180deg,#fffffffa,#fffefb);box-shadow:0 22px 44px #1522340f}.ebook-header span{color:var(--blue);font-size:13px}.ebook-header-top{display:flex;justify-content:space-between;gap:12px;align-items:center}.ebook-header-top em{font-style:normal;color:var(--muted);font-size:12px;letter-spacing:.08em;text-transform:uppercase}.ebook-header h4{margin:10px 0 8px;font-size:28px}.ebook-header p,.ebook-section p,.ebook-block p{color:var(--muted);line-height:1.8}.ebook-section{display:grid;gap:14px;margin-top:18px}.ebook-meta-strip{display:grid;gap:14px;margin-top:20px;padding:18px;border-radius:18px;background:#1f67b20d}.ebook-meta-strip p{margin:8px 0 0}.ebook-paragraph{display:grid;grid-template-columns:44px minmax(0,1fr);gap:14px;align-items:start}.ebook-paragraph-index{min-height:32px;border-radius:999px;display:inline-flex;align-items:center;justify-content:center;background:#ecf4ff;color:var(--blue);font-size:12px;font-weight:700}.ebook-section p,.ebook-block h5{margin:0}.ebook-block{margin-top:24px;padding-top:20px;border-top:1px solid var(--line)}.ebook-block h5{font-size:16px}.mindmap-stage,.knowledge-map-stage{display:none}.graph-canvas{margin-top:20px;overflow:auto;border-radius:30px;border:1px solid rgba(31,103,178,.08);background:#f9fbff;box-shadow:inset 0 0 0 1px #ffffff6b}.graph-surface{position:relative;margin:0 auto;background-image:radial-gradient(rgba(79,107,255,.12) 1px,transparent 1px);background-size:24px 24px}.mindmap-surface,.knowledge-map-surface{background-color:#fbfdff}.graph-svg{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;pointer-events:none}.graph-link{fill:none;stroke:var(--graph-color, #4f6bff);stroke-width:4px;stroke-linecap:round;opacity:.84}.graph-link--soft{stroke-width:3px;opacity:.62}.graph-link--bold{stroke-width:5px;opacity:.86}.graph-node{position:absolute;transform:translate(-50%,-50%);display:grid;align-content:center;gap:4px;text-align:center;z-index:1}.graph-node strong,.graph-node span{display:block}.graph-node--root,.graph-node--map-center{width:224px;min-height:112px;padding:18px 20px;border-radius:32px;background:linear-gradient(135deg,#2433a9,#4f6bff);color:#fff;box-shadow:0 26px 46px #2d45cf3d}.graph-node--root strong,.graph-node--map-center strong{font-size:34px;line-height:1.06}.graph-node--root span,.graph-node--map-center span{font-size:12px;color:#ffffffd1}.graph-node--branch,.graph-node--cluster{width:188px;min-height:78px;padding:14px 16px;border-radius:24px;background:var(--graph-color, #4f6bff);color:#fff;box-shadow:0 16px 30px color-mix(in srgb,var(--graph-color, #4f6bff) 28%,transparent)}.graph-node--branch strong,.graph-node--cluster strong{font-size:20px;line-height:1.15}.graph-node--branch span,.graph-node--cluster span{font-size:11px;color:#ffffffd1}.graph-node--leaf,.graph-node--map-leaf{min-height:44px;padding:0 18px;border-radius:999px;display:inline-flex;align-items:center;justify-content:center;background:#fff;border:3px solid var(--graph-color, #4f6bff);color:#24324a;box-shadow:0 12px 22px #111c2b14}.graph-node--leaf strong,.graph-node--map-leaf strong{font-size:14px;font-weight:600}.graph-node--leaf span,.graph-node--map-leaf span{display:none}.reader-card,.image-card{padding:18px;border-radius:20px;border:1px solid var(--line);background:var(--panel-strong)}.exercise-panel{display:grid;gap:16px}.exercise-summary-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.exercise-head-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.exercise-workbench-grid{display:grid;grid-template-columns:320px minmax(0,1fr);gap:14px}.exercise-list{display:grid;gap:14px}.exercise-card{padding:18px;border-radius:22px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.exercise-card--button{width:100%;text-align:left;cursor:pointer;transition:transform .18s ease,border-color .18s ease,box-shadow .18s ease}.exercise-card--button:hover{transform:translateY(-1px);border-color:#1f67b22e;box-shadow:0 14px 22px #111c2b0f}.exercise-card--active{border-color:#1f67b23d;background:linear-gradient(180deg,#eef7ff,#fff);box-shadow:inset 0 0 0 1px #1f67b21a}.exercise-card-top span,.exercise-card-top strong{display:block}.exercise-card-top span{color:var(--blue);font-size:12px}.exercise-card-top strong{margin-top:8px;font-size:18px;line-height:1.45}.exercise-card-body{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:16px}.exercise-card-body h5{margin:0;font-size:14px}.exercise-card-body p{margin:8px 0 0;color:var(--muted);line-height:1.7}.exercise-detail-card{padding:18px;border-radius:24px;border:1px solid var(--line);background:linear-gradient(180deg,#fff,#fbfdff)}.exercise-detail-head{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.exercise-detail-head h4{margin:8px 0 0;font-size:28px}.exercise-detail-head p{margin:10px 0 0;color:var(--muted);line-height:1.75}.exercise-mapping-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:16px}.exercise-mapping-card{padding:14px 16px;border-radius:18px;border:1px solid rgba(31,103,178,.08);background:#fffffff5}.exercise-mapping-card span,.exercise-mapping-card strong{display:block}.exercise-mapping-card span{color:var(--blue);font-size:12px}.exercise-mapping-card strong{margin-top:8px;line-height:1.6}.exercise-mapping-card p{margin:8px 0 0;color:var(--muted);line-height:1.7}.exercise-next-actions{display:grid;gap:10px;margin-top:16px;padding-top:16px;border-top:1px solid rgba(26,34,51,.08)}.exercise-footer-copy p{margin:10px 0 0;color:var(--muted);line-height:1.75}.outline-action--static{cursor:default}.outline-action--static:hover{color:var(--muted)}.exercise-footer-card{background:linear-gradient(180deg,#fff,#f8fbff)}.image-grid{grid-template-columns:repeat(auto-fit,minmax(180px,1fr))}.graph-node-button{position:absolute;border:0;background:transparent;padding:0;cursor:pointer}.graph-node-button:focus-visible .graph-node{outline:2px solid rgba(31,103,178,.65);outline-offset:4px}.book-feature-stack{display:grid;gap:14px}.book-overview-metrics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin-top:12px}.book-overview-tile{padding:14px 16px;border-radius:16px;border:1px solid rgba(31,103,178,.12);background:linear-gradient(180deg,#fff,#f7fbff)}.book-overview-tile strong,.book-overview-tile span{display:block}.book-overview-tile strong{font-size:24px;color:var(--blue)}.book-overview-tile span{margin-top:6px;color:var(--muted);font-size:12px}.book-overview-list,.cross-search-list,.pitfall-list{display:grid;gap:10px;margin-top:12px}.book-overview-row,.cross-search-item{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:12px 14px;border-radius:14px;border:1px solid var(--line);background:#fff}.book-overview-row span,.cross-search-item span{color:var(--blue);font-size:12px}.book-overview-row p,.cross-search-item p{margin:4px 0 0}.book-overview-row em{font-style:normal;color:var(--muted);font-size:12px}.book-plan-table{margin-top:8px;border:1px solid var(--line);border-radius:16px;overflow:hidden}.book-plan-head,.book-plan-row{display:grid;grid-template-columns:110px 2.3fr 110px 2fr 1.8fr;gap:10px;padding:12px 14px}.book-plan-head{background:#eef5fc;color:var(--blue);font-size:12px;font-weight:700}.book-plan-row{border-top:1px solid rgba(26,34,51,.06);font-size:13px}.coverage-grid{margin-top:12px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.coverage-card{padding:14px 16px;border-radius:16px;border:1px solid var(--line);background:#fff}.status-chip{margin-top:10px;min-height:26px;padding:0 10px;border-radius:999px;display:inline-flex;align-items:center;font-size:12px}.status-chip--good{background:#e8f8ef;color:#177245}.status-chip--warn{background:#fff4df;color:#9a5a00}.status-chip--bad{background:#ffecec;color:#b42318}.resource-pack-checks{display:flex;gap:14px;flex-wrap:wrap;margin-top:12px}.resource-pack-checks label{min-height:34px;border:1px solid var(--line);border-radius:999px;padding:0 12px;display:inline-flex;align-items:center;gap:6px;background:#fff}.cross-search-row{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:10px;margin-top:12px}.cross-search-row input{min-height:40px;border-radius:999px;border:1px solid var(--line);padding:0 14px;background:#fff}.pitfall-card{padding:14px 16px;border-radius:16px;border:1px solid var(--line);background:#fff}.pitfall-card-top{display:flex;justify-content:space-between;gap:10px;align-items:center}.pitfall-card-top span{font-size:12px;color:var(--blue)}.asset-filter-row{margin-top:12px;display:grid;gap:10px}.asset-filter-group{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.asset-filter-group span{color:var(--muted);font-size:12px}.asset-filter-chip{min-height:30px;border-radius:999px;border:1px solid var(--line);background:#fff;padding:0 10px;cursor:pointer;font-size:12px}.asset-filter-chip--active{border-color:#1f67b23d;background:#eaf4ff;color:var(--blue);box-shadow:inset 0 0 0 1px #1f67b21a}.asset-table{border:1px solid var(--line);border-radius:16px;overflow:hidden}.asset-table-head,.asset-table-row{display:grid;grid-template-columns:1.5fr 90px 1.6fr 90px 1.4fr 120px;gap:10px;padding:12px 14px;align-items:center}.asset-table-head{background:#eef5fc;color:var(--blue);font-size:12px;font-weight:700}.asset-table-row{border-top:1px solid rgba(26,34,51,.06);background:#fff;font-size:13px}.asset-table-row em{font-style:normal}.image-placeholder{height:140px;border-radius:16px;margin-bottom:12px;background:linear-gradient(135deg,#1f67b21a,#1f67b205),repeating-linear-gradient(135deg,#1f67b214 0,#1f67b214 12px,#ffffffb3 12px,#ffffffb3 24px)}.collapse-toggle{width:100%;display:flex;justify-content:space-between;align-items:center;gap:12px;padding:0;border:0;background:transparent;cursor:pointer;color:inherit}.collapse-toggle h3{margin:0;font-size:19px}.collapse-chevron{flex-shrink:0;color:var(--muted);transition:transform .22s ease}.collapse-toggle--open .collapse-chevron{transform:rotate(180deg)}.collapse-body{margin-top:16px;padding-top:16px;border-top:1px solid var(--line)}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:1000;display:grid;place-items:center;padding:24px;background:#111a2766;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px)}.modal-card{width:min(760px,100%);max-height:calc(100vh - 48px);overflow:auto;border-radius:28px;border:1px solid rgba(255,255,255,.22);background:#fffffff5;box-shadow:0 24px 60px #0f172a38;padding:24px}.modal-head{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.modal-kicker{margin:0 0 6px;color:var(--blue);font-size:12px}.modal-head h3{margin:0;font-size:28px}.modal-description{margin:10px 0 0;color:var(--muted);line-height:1.7}.modal-close{border:0;background:transparent;color:var(--muted);cursor:pointer}.modal-body{display:grid;gap:18px;margin-top:22px}.modal-section h4{margin:0 0 12px;font-size:16px}.modal-chapter-box,.modal-field-row{border-radius:18px;border:1px solid var(--line);background:#fbfdff}.modal-chapter-box{padding:18px}.modal-chapter-box strong{display:block}.modal-chapter-box p{margin:8px 0 0;color:var(--muted);line-height:1.7}.modal-field-list{display:grid;gap:10px}.modal-field-row{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:14px 16px}.modal-field-row span{color:var(--muted);font-size:14px}.modal-preview-list{display:flex;flex-wrap:wrap;gap:10px}.modal-preview-list span{min-height:34px;padding:0 12px;border-radius:999px;display:inline-flex;align-items:center;background:#eaf4ff;color:var(--blue);font-size:13px}.modal-actions{display:flex;justify-content:flex-end;gap:12px;margin-top:24px}.drawer-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:1000;display:flex;justify-content:flex-end;background:#111a2757;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px)}.drawer-panel{width:min(560px,100%);height:100vh;overflow:auto;padding:24px;background:#fffffffa;box-shadow:-20px 0 40px #0f172a1f}.drawer-head{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.drawer-body{display:grid;gap:20px;margin-top:24px}.drawer-section h4{margin:0 0 12px;font-size:16px}.drawer-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.drawer-field{display:grid;gap:8px}.drawer-field span{color:var(--muted);font-size:13px}.drawer-field select,.drawer-field input,.drawer-textarea{border-radius:16px;border:1px solid var(--line-strong);background:#fff;padding:12px 14px;font:inherit}.drawer-chip-grid{display:flex;flex-wrap:wrap;gap:10px}.drawer-choice-chip{min-height:40px;padding:0 16px;border-radius:999px;border:1px solid var(--line);background:#fff;color:var(--text);cursor:pointer}.drawer-choice-chip--active{border-color:#1f67b22e;background:#eef5fc;color:var(--blue);box-shadow:inset 0 0 0 1px #1f67b214}.drawer-textarea{min-height:120px;resize:none;color:var(--muted);line-height:1.7}.drawer-checkboxes{display:grid;gap:10px}.drawer-check{display:flex;align-items:center;gap:10px;padding:12px 14px;border-radius:16px;border:1px solid var(--line);background:#fbfdff}.drawer-actions{display:flex;justify-content:flex-end;gap:12px;margin-top:24px}.hotspot-selector-list{display:grid;gap:10px}.hotspot-selector-item{display:grid;grid-template-columns:auto minmax(0,1fr);gap:10px;align-items:flex-start;padding:12px;border-radius:14px;border:1px solid var(--line);background:#fff}.hotspot-selector-item--active{border-color:#1f67b23d;background:#f7fbff}.hotspot-selector-item strong{display:block}.hotspot-selector-item p{margin:8px 0 0;color:var(--muted);line-height:1.65}.hotspot-target-grid{display:flex;flex-wrap:wrap;gap:8px}@media(max-width:1180px){.shell{grid-template-columns:1fr}.sidebar{border-right:0;border-bottom:1px solid rgba(26,34,51,.06)}.page-grid,.assistant-layout,.library-shell,.reader-shell,.catalog-workspace,.library-hero,.lesson-plan-shell,.exercise-workspace-shell,.ppt-workspace-shell,.board-workspace-shell,.chapter-status-strip,.chapter-entry-grid,.chapter-resource-grid,.chapter-summary-top,.chapter-info-strip,.topic-hook-grid,.mapping-grid,.exercise-workbench-grid,.exercise-mapping-grid,.qa-interaction-grid,.summary-grid,.chapter-overview-grid,.exercise-summary-grid,.exercise-card-body,.ebook-meta-strip,.book-overview-metrics,.coverage-grid,.cross-search-row,.asset-table-head,.asset-table-row,.ppt-edit-grid,.exercise-edit-grid,.board-edit-grid,.board-column-grid,.drawer-grid,.prep-entry-form,.topic-teaching-grid,.topic-list--detailed,.topic-list--asset-pack,.materials-grid{grid-template-columns:1fr}.reader-menu,.reader-content{min-height:auto}}@media(max-width:720px){.main,.sidebar{padding:18px}.topbar,.section-head,.topic-top,.chapter-center-head,.chapter-detail-entry,.chapter-detail-drawer-head,.exercise-detail-head,.qa-card-head,.topic-hook-top,.content-head,.modal-head,.lesson-plan-topbar,.exercise-topbar,.ppt-topbar,.board-topbar,.ppt-preview-topbar,.drawer-head,.lesson-edit-head,.exercise-edit-head,.ppt-edit-head,.board-edit-head,.lesson-alt-top{flex-direction:column;align-items:stretch}.chat-input{grid-template-columns:1fr}.context-row{gap:6px}.book-cover{min-height:220px}.book-cover strong,.shelf-meta h4,.ebook-header h4,.modal-head h3{font-size:24px}.library-hero-copy h3,.chapter-stage-head h3{font-size:28px}.chapter-stage-head{flex-direction:column;align-items:stretch}.chapter-head-actions,.chapter-ability-row,.exercise-head-actions{justify-content:flex-start}.chapter-entry-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.lesson-plan-topbar h2,.exercise-topbar h2,.ppt-topbar h2,.ppt-slide-canvas h3{font-size:28px}.ppt-preview-slide h2{font-size:30px}.board-topbar h2,.board-header h3{font-size:28px}.ppt-preview-controls{flex-direction:column}.ebook{padding:20px}.ebook-paragraph,.modal-field-row,.modal-actions{grid-template-columns:1fr}.ebook-paragraph,.modal-actions,.drawer-actions{display:grid}.drawer-panel,.chapter-detail-drawer{width:100%}.book-plan-head,.book-plan-row{grid-template-columns:1fr}}
