:root{--color-primary: #3380f7;--color-primary-hover: #2563eb;--color-primary-soft: #eff6ff;--color-bg-page: #fdfbf7;--color-bg-surface: #ffffff;--color-bg-muted: #f3f4f6;--color-text: #111827;--color-text-secondary: #6b7280;--color-text-tertiary: #9ca3af;--color-border: #e5e7eb;--shadow-sm: 0 1px 3px rgb(0 0 0 / 6%);--shadow-md: 0 2px 12px rgb(0 0 0 / 6%);--color-success: #166534;--color-success-bg: #dcfce7;--color-danger: #991b1b;--color-danger-bg: #fee2e2;--color-warning-bg: #fffbeb;--color-warning-border: #fde68a;--color-boy: #73a0d9;--color-girl: #d9a6bf;--radius-sm: 8px;--radius-md: 12px;--radius-lg: 16px;--text-display: 2rem;--text-h1: 1.5rem;--text-h2: 1.25rem;--text-h3: 1.125rem;--text-body: 1rem;--text-body-lg: 1.125rem;--text-caption: .875rem;--text-label: .875rem;--shell-max-width: 960px;--shell-padding-x: 24px}@media(max-width:1023px){:root{--shell-max-width: 720px;--shell-padding-x: 20px}}@media(max-width:767px){:root{--shell-max-width: 100%;--shell-padding-x: 16px;--text-h1: 1.375rem}}:root{--primary: var(--color-primary);--primary-dark: var(--color-primary-hover);--bg: var(--color-bg-page);--card: var(--color-bg-surface);--text: var(--color-text);--muted: var(--color-text-secondary);--border: var(--color-border);--pass: var(--color-success);--pass-bg: var(--color-success-bg);--fail: var(--color-danger);--fail-bg: var(--color-danger-bg);--radius: var(--radius-md);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,PingFang SC,Hiragino Sans GB,Microsoft YaHei,sans-serif}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font-size:var(--text-body);line-height:1.6}code{font-size:.9em;background:#eef2ff;padding:.1em .35em;border-radius:4px}.top{background:var(--card);border-bottom:1px solid var(--border);box-shadow:var(--shadow-sm)}.top-inner{display:flex;align-items:center;gap:20px;max-width:var(--shell-max-width);margin:0 auto;padding:14px var(--shell-padding-x);flex-wrap:wrap}.brand{font-size:var(--text-h3);font-weight:700;color:var(--primary);text-decoration:none;flex-shrink:0}.brand:hover{color:var(--primary-dark)}.top-actions{display:flex;align-items:center;gap:14px;margin-left:auto;flex-shrink:0}.top-site-link{color:var(--muted);text-decoration:none;font-size:var(--text-caption);font-weight:500}.top-site-link:hover{color:var(--primary)}.shell{max-width:var(--shell-max-width);margin:0 auto;padding:28px var(--shell-padding-x) 56px}.page-title,h1{margin:0 0 12px;font-size:var(--text-h1);font-weight:700;line-height:1.3}.lead{margin:0 0 20px;color:var(--muted);font-size:var(--text-body)}.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:20px;margin-bottom:16px;box-shadow:0 1px 3px #0f172a0f}.card h2{margin:0 0 14px;font-size:var(--text-h2);font-weight:600}.field{display:block;margin-bottom:14px}.field span{display:block;font-size:var(--text-label);font-weight:600;margin-bottom:6px;color:var(--muted)}.field input,.field select{width:100%;padding:10px 12px;font-size:1rem;border:1px solid var(--border);border-radius:8px}.target-display{font-size:var(--text-body-lg);font-weight:600;padding:16px;background:var(--color-bg-muted);border-radius:var(--radius-sm);min-height:3rem}.target-display mark.miss{background:#fecaca;color:var(--fail);padding:0 2px;border-radius:3px}.muted{color:var(--muted);font-weight:400;font-size:1rem}.hint{font-size:.9rem;color:var(--muted);margin:0 0 16px}.btn-row{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:12px}.btn{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:10px 18px;font-size:var(--text-body);font-weight:600;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--card);cursor:pointer}.btn:disabled{opacity:.5;cursor:not-allowed}.btn.primary{background:var(--primary);border-color:var(--primary);color:#fff}.btn.primary:hover:not(:disabled){background:var(--primary-dark)}.btn.assess{width:100%;margin-top:8px;min-height:48px;padding:14px;font-size:var(--text-h3);background:linear-gradient(135deg,var(--color-primary),var(--color-primary-hover));border:none;color:#fff}.rec-state{font-size:.9rem;color:var(--muted);margin:0 0 8px}.status-list{margin:0;padding-left:1.2rem;font-size:.9rem}.status-list li{margin-bottom:6px}.result-card.hidden{display:none}#result-title.pass{color:var(--pass)}#result-title.fail{color:var(--fail)}#result-summary{font-size:1rem;margin:0 0 8px}.meta{font-size:.85rem;color:var(--muted);margin:0 0 12px}.detail{display:grid;grid-template-columns:auto 1fr;gap:6px 12px;margin:0;font-size:.85rem}.detail dt{color:var(--muted);font-weight:600}.detail dd{margin:0;word-break:break-word}.notes ul{margin:0;padding-left:1.2rem;font-size:.9rem;color:var(--muted)}.notes li{margin-bottom:8px}.top-nav{display:flex;gap:4px 20px;flex:1;justify-content:center;flex-wrap:wrap}.top-nav a{color:var(--muted);text-decoration:none;font-weight:600;font-size:var(--text-body);padding:8px 4px;border-bottom:2px solid transparent;min-height:44px;display:inline-flex;align-items:center}.top-nav a.active{color:var(--primary);border-bottom-color:var(--primary)}.top-nav a:hover{color:var(--primary)}.top-actions a{color:var(--muted);text-decoration:none;font-weight:600;font-size:var(--text-caption);min-height:44px;display:inline-flex;align-items:center}.top-actions a:hover{color:var(--primary)}.top-actions .nav-logout{border:none;background:none;color:var(--muted);font-weight:600;font-size:var(--text-caption);cursor:pointer;padding:0;min-height:44px}.top-actions .nav-logout:hover{color:var(--primary)}.book-list,.lesson-list{list-style:none;margin:0;padding:0}.book-item,.lesson-list li{margin-bottom:8px}.book-link,.lesson-link{width:100%;text-align:left;padding:14px 16px;border:1px solid var(--border);border-radius:8px;background:#fff;cursor:pointer}.book-link:hover,.lesson-link:hover{border-color:var(--primary);background:#f8fbff}.book-pub,.lesson-name{display:block;font-weight:600}.book-grade,.book-isbn,.lesson-id{display:block;font-size:.85rem;color:var(--muted);margin-top:4px}.unit-block h2{font-size:1rem;margin:20px 0 10px;color:var(--muted)}.linkish{background:none;border:none;color:var(--primary);cursor:pointer;font:inherit;padding:0}.meta-line{color:var(--muted);font-size:.9rem;margin:-8px 0 16px}.summary{background:#f0f9ff;border:1px solid #bae6fd;border-radius:8px;padding:12px 14px;margin-bottom:16px;font-size:.95rem}.notice.warn{background:#fffbeb;border:1px solid #fcd34d;border-radius:8px;padding:12px 14px;margin-bottom:16px;font-size:.9rem}.notice a{color:var(--primary)}.line-row{display:flex;gap:12px;align-items:flex-start;padding:12px 0;border-bottom:1px solid var(--border)}.line-row:last-child{border-bottom:none}.line-text{flex:1;min-width:0}.line-text .en{margin:0;font-weight:600;font-size:var(--text-body-lg);line-height:1.5}.line-text .zh{margin:4px 0 0;font-size:var(--text-caption);color:var(--muted)}.follow-btn{flex-shrink:0;white-space:nowrap}.type-tag{font-size:.75rem;font-weight:500;color:var(--muted)}.loading,.error-box{padding:32px 16px;text-align:center;color:var(--muted)}.state-panel{max-width:var(--shell-max-width);margin:0 auto;padding:48px var(--shell-padding-x)}.loading{display:flex;flex-direction:column;align-items:center;gap:16px}.loading p{margin:0;font-size:var(--text-body)}.loading-spinner{width:36px;height:36px;border:3px solid var(--color-border);border-top-color:var(--primary);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@media(prefers-reduced-motion:reduce){.loading-spinner{animation:none;border-top-color:var(--color-border)}}.error-box{max-width:420px;margin:0 auto;padding:28px 24px;background:var(--card);border:1px solid var(--color-border);border-radius:var(--radius-md);box-shadow:var(--shadow-md)}.error-box__title{margin:0 0 8px;font-size:var(--text-h3);font-weight:700;color:var(--text)}.error-box__msg{margin:0 0 20px;font-size:var(--text-body);color:var(--muted);line-height:1.55}body.modal-open{overflow:hidden}.follow-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:1000;background:#0f172a73;display:flex;align-items:flex-end;justify-content:center;padding:0}.follow-sheet{width:100%;max-width:640px;max-height:92vh;overflow:auto;background:var(--card);border-radius:var(--radius-lg) var(--radius-lg) 0 0;padding:20px 24px 32px;box-shadow:0 -4px 24px #0f172a26}@media(min-width:768px)and (max-width:1023px){.follow-overlay{align-items:center;justify-content:center;padding:24px}.follow-sheet{max-width:560px;max-height:90vh;border-radius:var(--radius-lg);box-shadow:var(--shadow-md)}}@media(min-width:1024px){.follow-overlay{align-items:stretch;justify-content:flex-end}.follow-sheet{width:min(440px,38vw);max-width:none;max-height:none;height:100%;border-radius:var(--radius-lg) 0 0 var(--radius-lg);padding:24px 28px 32px;box-shadow:-8px 0 32px #0f172a1f}.follow-body{display:flex;flex-direction:column;min-height:calc(100% - 48px)}.follow-sheet .btn.assess{margin-top:auto}}.follow-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:12px}.follow-head h2{margin:0;font-size:var(--text-h2);font-weight:700}.icon-btn{min-width:44px;min-height:44px;padding:8px 12px;font-size:1.125rem;line-height:1}.translation{color:var(--muted);margin:0 0 12px}.follow-result.hidden{display:none}.pass-msg{color:var(--pass);font-weight:700;font-size:var(--text-h2);margin:0 0 8px}.fail-msg{color:var(--fail);font-weight:700;font-size:var(--text-h2);margin:0 0 8px}.follow-result-box{margin-top:16px;padding:16px;border-radius:var(--radius-sm)}.follow-result-box--pass{background:var(--pass-bg);border:1px solid #86efac}.follow-result-box--fail{background:var(--fail-bg);border:1px solid #fecaca}.follow-result-box .meta{margin:0;font-size:var(--text-caption)}.hint.subtle{margin-top:-8px;font-size:.85rem;color:var(--primary)}.hint.subtle[hidden]{display:none}.karaoke-target.karaoke-mode{line-height:1.6}.karaoke-unit{display:inline-block;margin-right:.2em;padding:0 2px;border-radius:4px;transition:background .1s,color .1s}.karaoke-unit.active{background:#fef08a;color:var(--text)}.review-list{list-style:none;margin:0;padding:0}.review-item{margin-bottom:10px}.review-link{width:100%;text-align:left;padding:14px 16px;border:1px solid var(--border);border-radius:8px;background:#fff;cursor:pointer}.review-link:hover{border-color:var(--primary);background:#f8fbff}.review-text{display:block;font-weight:600;margin-bottom:6px}.review-meta{display:flex;flex-wrap:wrap;gap:8px;align-items:center;font-size:.85rem;color:var(--muted)}.tag{font-size:.75rem;font-weight:700;padding:2px 8px;border-radius:999px}.tag.pass{background:var(--pass-bg);color:var(--pass)}.tag.fail{background:var(--fail-bg);color:var(--fail)}.featured-story h2{margin-top:0}.story-featured-btn{display:flex;gap:14px;align-items:flex-start;width:100%;padding:12px;border:1px solid var(--border);border-radius:8px;background:#f8fbff;cursor:pointer;text-align:left}.story-featured-btn:hover{border-color:var(--primary)}.story-thumb,.story-list-thumb{width:56px;height:56px;object-fit:cover;border-radius:8px;flex-shrink:0}.story-list-thumb{width:40px;height:40px;margin-left:auto}.block{display:block;margin-top:4px}.lesson-link{display:flex;align-items:center;gap:10px;width:100%}.preview-actions{margin:20px 0}.preview-action-btn{display:flex;gap:14px;align-items:flex-start;width:100%;padding:16px;text-align:left}.preview-action-icon{font-size:1.75rem;line-height:1}.textbook-card-list{list-style:none;margin:0;padding:0;display:grid;gap:12px}@media(min-width:1024px){.textbook-card-list{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.lesson-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.lesson-list li{margin-bottom:0}}.textbook-card-item{margin-bottom:12px}.textbook-card-btn{display:flex;gap:14px;width:100%;padding:14px 16px;border:1px solid var(--border);border-radius:var(--radius);background:var(--card);cursor:pointer;text-align:left}.textbook-card-btn:hover{border-color:var(--primary);background:#f8fbff}.textbook-card-icon{font-size:1.5rem;flex-shrink:0}.textbook-card-body{display:flex;flex-direction:column;gap:4px;min-width:0}.textbook-card-grade{font-size:1.05rem}.textbook-card-pub{font-size:.85rem;color:var(--muted)}.book-meta-line{display:block;font-size:.8rem;color:var(--muted)}.review-card-link{display:flex;gap:14px;align-items:flex-start}.review-thumb{font-size:1.75rem;flex-shrink:0;line-height:1.2}.review-card-body{flex:1;min-width:0}.vocab-word{color:var(--primary);font-weight:700}.grammar-item{margin-bottom:14px;padding-bottom:14px;border-bottom:1px solid var(--border)}.grammar-item:last-child{margin-bottom:0;padding-bottom:0;border-bottom:none}.grammar-rule{margin:0 0 8px;font-weight:600}.subtext{margin:4px 0 0;font-size:.85rem;color:var(--muted)}.exercise-row{margin-bottom:12px}.exercise-pairs{margin:6px 0 0;padding-left:1.2rem;font-size:.9rem;color:var(--muted)}.empty-state{padding:40px 24px;text-align:center;background:var(--card);border:1px solid var(--border);border-radius:var(--radius-md);box-shadow:var(--shadow-sm)}.empty-state__icon{font-size:2.5rem;line-height:1;margin-bottom:12px}.empty-state .muted{font-size:var(--text-body);line-height:1.6;max-width:28rem;margin:0 auto 8px}.empty-state .btn{margin-top:16px}@media(min-width:1024px){.review-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.review-item{margin-bottom:0}}@media(max-width:767px){.top-inner{gap:12px}.top-nav{order:3;width:100%;justify-content:flex-start}.top-actions{margin-left:0}}