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button.textbook-directory-trigger{display:none}.textbook-drawer-overlay{z-index:1200;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);background:#123a3066;justify-content:flex-end;display:flex;position:fixed;inset:0}.textbook-drawer{background:var(--white,#fff);width:min(420px,100vw);height:100dvh;padding:24px;overflow-y:auto;box-shadow:-12px 0 50px #163f3820}.textbook-drawer header{z-index:1;background:var(--white,#fff);justify-content:space-between;align-items:center;gap:16px;margin-bottom:24px;padding:8px 0 16px;display:flex;position:sticky;top:0}.textbook-drawer header h2{margin:0;font-size:20px}.textbook-drawer header button{background:var(--paper,#f5faf7);border:1px solid var(--line);border-radius:var(--radius-control,12px);flex:none;justify-content:center;align-items:center;width:44px;height:44px;display:inline-flex}:is(.textbook-learning button:focus-visible,.textbook-learning select:focus-visible){outline:3px solid var(--subject-accent);outline-offset:3px}.textbook-reading-heading h2:focus{outline:none}@media (max-width:1180px){.textbook-workspace{grid-template-columns:1fr}.textbook-directory{display:none}.textbook-learning button.textbook-directory-trigger{text-align:left;justify-content:flex-start;max-width:100%;margin-bottom:16px;display:flex}.textbook-directory-trigger svg:last-child{margin-left:auto}.textbook-course-heading{gap:12px}.textbook-course-heading label{gap:6px;display:grid}.textbook-course-heading p span{display:block}.textbook-save-status{max-width:170px}}@media (max-width:600px){.textbook-learning{margin-top:12px}.textbook-subject-tabs{gap:8px;margin-bottom:14px}.textbook-subject-tabs button{flex:1;gap:6px;min-width:0;padding:10px 8px;font-size:15px}.textbook-subject-tabs button span{display:none}.textbook-course-heading{flex-wrap:wrap;margin-bottom:16px;padding:14px}.textbook-course-icon{display:none}.textbook-course-heading>div{flex:100%}.textbook-course-heading p span{display:inline}.textbook-save-status{max-width:none}.textbook-body{padding:20px 16px}.textbook-reading-heading h2{font-size:22px}.textbook-welcome{padding:26px 4px}.textbook-welcome h2{font-size:21px}.textbook-error{flex-wrap:wrap}.textbook-drawer{width:100%;padding:20px}.textbook-learning button.textbook-directory-trigger{width:100%;font-size:14px}.textbook-learning[data-subject=chinese]{margin-top:4px}.textbook-learning[data-subject=chinese] .textbook-subject-tabs{margin-bottom:9px}.textbook-learning[data-subject=chinese] .textbook-course-heading{gap:3px;margin-bottom:10px;padding:9px 11px}.textbook-learning[data-subject=chinese] .textbook-course-heading label{align-items:center;gap:6px;display:flex}.textbook-learning[data-subject=chinese] .textbook-course-heading label>span{white-space:nowrap;font-size:12px}.textbook-learning[data-subject=chinese] .textbook-course-heading select{min-height:44px;font-size:13px}.textbook-learning[data-subject=chinese] .textbook-course-heading p{display:none}.textbook-learning[data-subject=chinese] .textbook-save-status{font-size:11px}.textbook-learning[data-subject=chinese] .textbook-reading-heading{display:none}.textbook-learning[data-subject=chinese] .textbook-body{padding:14px 13px}.textbook-learning[data-subject=chinese] button.textbook-directory-trigger{margin-bottom:10px}}@media (prefers-reduced-motion:reduce){.textbook-subject-tabs button,.textbook-topics button{transition:none}.textbook-subject-tabs button:hover:not(:disabled):hover{transform:none}}