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.small-muted{font-size:10px;color:#a3afb0;margin-top:9px}.backup-divider{border-top:1px solid #edf1ef;margin:26px 0}.file-label{cursor:pointer}.meter{height:7px;background:#ecf2f0;border-radius:20px;margin-top:22px;overflow:hidden}.meter-fill{height:100%;width:0%;background:linear-gradient(90deg,#72b39d,#d0bd72);transition:width .2s}.meter-caption{font-size:11px;color:#8d9e9e;margin-top:8px}.security-panel{border:1px solid #eadfd0;border-radius:13px;padding:21px 25px;background:#fffaf3;margin-top:20px}.security-panel b{font-size:13px;color:#815f3f}.security-panel p{font-size:11px;line-height:1.85;margin-top:8px;color:#947d67}.storage-info{margin-top:9px;color:#a28a71;font-size:10px}.toast{position:fixed;bottom:calc(25px + var(--safe-bottom));left:50%;transform:translateX(-50%);background:#263e49;color:white;padding:12px 18px;border-radius:10px;box-shadow:0 8px 33px 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@media(max-width:1180px){.sidebar{width:235px;flex-basis:235px}.content{padding:29px 27px 50px}.hero{padding:36px}.hero h1{font-size:32px}.subject-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:820px){.topbar{height:66px;padding:0 18px}.menu-toggle{display:block;margin-right:7px}.brand{margin-right:auto}.brand-mark{width:37px;height:37px;font-size:24px}.brand-text b{font-size:14px}.brand-text small{font-size:9px}.topbar-actions{gap:8px}.topbar-actions .online-indicator{font-size:10px}.mini-backup{display:none}.layout{min-height:calc(100vh - 66px)}.sidebar{position:fixed;z-index:65;top:0;left:0;height:100dvh;max-height:100dvh;width:min(320px,85vw);transform:translateX(-100%);transition:transform .24s;box-shadow:6px 0 30px #0e313125;padding-top:25px}.sidebar.open{transform:translateX(0)}.close-nav{display:block}.shade{position:fixed;z-index:60;inset:0;background:#12272d80}.shade.show{display:block}.content{padding:23px 19px 95px}.hero{grid-template-columns:1fr;min-height:252px;padding:30px 30px 35px}.hero-art{display:none}.stats-row{grid-template-columns:repeat(2,minmax(0,1fr))}.subject-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.backup-grid{grid-template-columns:1fr}.practice-heading{flex-direction:column;align-items:stretch}.practice-heading-right{width:100%}.search-box{width:100%}.bottom-nav{display:flex;position:fixed;bottom:0;left:0;right:0;z-index:40;background:#fff;box-shadow:0 -3px 20px #1c334610;border-top:1px solid var(--line);padding:8px 5px calc(7px + var(--safe-bottom));justify-content:space-around}.bottom-nav button{border:0;background:none;display:flex;flex-direction:column;gap:3px;align-items:center;min-width:58px;color:#7f9298;font-size:10px;padding:3px}.bottom-nav button.active{color:#bc713d;font-weight:750}.bottom-nav button span{font-size:21px;font-family:Georgia,serif}.main-footer{padding:20px 25px calc(90px + var(--safe-bottom))}.toast{bottom:calc(80px + var(--safe-bottom))}}
@media(max-width:520px){.topbar{padding:0 10px}.brand-mark{width:34px;height:34px}.brand-text b{font-size:12px}.brand-text small{font-size:8px}.online-indicator{font-size:0!important}.online-indicator::first-letter{font-size:12px}.hero{padding:27px 22px 30px}.hero h1{font-size:27px}.hero-copy>p{font-size:11px}.hero-actions{gap:8px}.hero .btn{padding:10px 12px;font-size:11px}.section-head h2{font-size:18px}.section-head{margin-top:28px}.section-head small{max-width:90px;text-align:right}.stats-row{gap:9px}.stat-card{min-height:115px;padding:14px 15px}.stat-val{font-size:27px}.stat-desc{font-size:9px}.stat-label{font-size:11px}.subject-grid{grid-template-columns:1fr}.subject-card{min-height:97px;gap:7px;padding:16px}.subject-card .subject-icon{width:27px;height:27px}.offline-note{flex-wrap:wrap;gap:12px;padding:16px}.offline-note .btn{width:100%}.study-toolbar{padding:10px;flex-wrap:wrap}.toolbar-left,.toolbar-right{justify-content:space-between;flex:1}.toolbar-right{width:100%}.question-panel{padding:17px 17px 21px}.question-meta{align-items:flex-start}.q-stem{font-size:15px}.mastery-bar{gap:7px}.mastery-label{width:100%;flex:auto}.mastery-chip{padding:9px 10px}.practice-footer{gap:4px}.practice-footer .btn{min-width:0;padding:10px 9px;font-size:11px}.question-jump input{width:42px}.question-jump label{display:none}.question-jump{gap:2px}.page-heading h1{font-size:27px}.page-heading p{font-size:12px}.panel{padding:19px}.toast{width:90%}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}

/* V2: accessibility and provenance improvements */
.source-caution{margin:16px 0 8px;border:1px solid #e2d9c8;background:#f9f6ee;border-radius:12px;padding:15px 18px;display:flex;gap:9px;align-items:baseline;line-height:1.65;font-size:12px;color:#554e40}.source-caution b{white-space:nowrap;color:#9c6332}.backup-reminder{background:#f0f5f3;border-left:3px solid #587c73;border-radius:4px;padding:9px 11px;font-size:12px;line-height:1.6;color:#284f48}.q-option:focus-visible,.btn:focus-visible,.nav-link:focus-visible,.mastery-chip:focus-visible,.cat-node:focus-visible,.bottom-nav button:focus-visible{outline:3px solid #b77b3c;outline-offset:3px}@media(max-width:520px){.source-caution{flex-direction:column;gap:3px;margin-top:14px}.q-option{min-height:49px}.mastery-chip{min-height:44px}}

/* Prevent Safari's automatic page zoom when editing smaller input controls. */
@media(hover:none) and (pointer:coarse){input,select,textarea{font-size:16px!important}.practice-footer .question-jump input{width:54px;min-height:44px}}

.ios-storage-tip{font-weight:650;color:#275e68;background:#eff6f6;border-radius:8px;padding:12px 14px;line-height:1.7}
.topic-callout{display:flex;align-items:center;gap:22px;justify-content:space-between;padding:24px;margin-top:26px;background:#edf5f2;border:1px solid #d5e5df;border-radius:14px}.topic-callout strong{font-size:17px;color:#284e49}.topic-callout p{font-size:12px;color:#6d8981;line-height:1.85;margin-top:8px}.topic-controls{display:flex;gap:18px;padding:20px;border:1px solid var(--line);border-radius:13px;background:#fff}.topic-controls label{display:grid;gap:8px;color:#6e8588;font-size:12px}.topic-controls select,.topic-controls input{min-height:44px;padding:10px 13px;border:1px solid #d6e2df;border-radius:8px;background:#f8fbfa;color:#28434c;min-width:170px}.topic-search-label{flex:1}.topic-controls input{width:100%}.topic-chapters{display:flex;flex-wrap:wrap;gap:8px;margin:20px 0}.chapter-chip{min-height:44px;border:1px solid #dce5e2;border-radius:100px;background:#fff;padding:10px 17px;color:#687f84;font-size:12px}.chapter-chip[aria-pressed="true"]{background:#24434a;color:#fff;border-color:#24434a}.topic-summary{display:flex;align-items:center;justify-content:space-between;gap:15px;margin:30px 0 8px}.topic-summary h2{font-size:27px;margin:8px 0}.topic-summary p{font-size:12px;color:#80928f;line-height:1.8}.topic-section{margin:30px 0}.topic-section h3{font-size:17px;display:flex;align-items:center;gap:12px;margin-bottom:14px}.topic-section h3>span{font-size:11px;color:#8c9c9a;font-weight:400}.topic-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:13px}.topic-card{min-width:0;display:flex;flex-direction:column;text-align:left;gap:10px;background:#fff;border:1px solid #e0e9e4;border-radius:13px;padding:21px;color:var(--ink);box-shadow:var(--shadow)}.topic-card:hover{border-color:#91b7a9;background:#fcfefd}.topic-path{font-size:11px;color:#92a49e;line-height:1.6}.topic-card strong{font-size:16px;line-height:1.6}.topic-card-count{display:flex;justify-content:space-between;gap:9px;color:#4b7970;font-size:12px;margin-top:auto}.topic-card-count>span{font-size:11px;color:#819a94}.topic-meter{height:4px;border-radius:5px;overflow:hidden;background:#edf2ef;margin-top:5px}.topic-meter>span{display:block;height:100%;background:#639f85}.topic-card-progress{font-size:11px;color:#93a59d}.topic-card:focus-visible,.chapter-chip:focus-visible{outline:3px solid #b77b3c;outline-offset:3px}@media(max-width:820px){.topic-callout{align-items:stretch;flex-direction:column;gap:15px}.topic-callout .btn{align-self:flex-start}.topic-grid{gap:11px}.topic-card{padding:17px}.topic-summary{align-items:flex-start}}@media(max-width:520px){.topic-controls{flex-direction:column;padding:16px;gap:14px}.topic-controls select{width:100%}.topic-grid{grid-template-columns:1fr}.topic-summary{flex-direction:column;gap:12px}.topic-summary .btn{width:100%}.topic-callout{padding:20px}.topic-callout .btn{width:100%}.topic-callout strong{font-size:16px}.topic-chapters{gap:7px}.chapter-chip{padding:10px 14px}}