:root{color-scheme:light}
:root[data-theme="dark"]{color-scheme:dark;--theme-page:#151a18;--theme-surface:#1e2522;--theme-surface-2:#252e2a;--theme-text:#e4e9e3;--theme-muted:#a7b2aa;--theme-line:#37433d;--theme-accent:#a9c8a6;--theme-accent-soft:#2b3a30;--theme-shadow:0 12px 34px #080d0b50;--bg:var(--theme-page);--white:var(--theme-surface);--text:var(--theme-text);--muted:var(--theme-muted);--green:#91b796;--green2:#a9c7a5;--lime:#425a43;--line:var(--theme-line)}
:root[data-theme="dark"] body{background:var(--theme-page);color:var(--theme-text)}
:root[data-theme="dark"] header,:root[data-theme="dark"] .site-head,:root[data-theme="dark"] .home-head{background:var(--theme-surface);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] header a,:root[data-theme="dark"] .site-head a,:root[data-theme="dark"] .home-head a{color:inherit}
:root[data-theme="dark"] main,:root[data-theme="dark"] .summary,:root[data-theme="dark"] .card,:root[data-theme="dark"] .exercise-card,:root[data-theme="dark"] .library,:root[data-theme="dark"] .settings,:root[data-theme="dark"] .guide,:root[data-theme="dark"] .answer-panel,:root[data-theme="dark"] .question-paper,:root[data-theme="dark"] .part-review,:root[data-theme="dark"] .attempt-card,:root[data-theme="dark"] .response-section,:root[data-theme="dark"] .reading-shell,:root[data-theme="dark"] .setup-card,:root[data-theme="dark"] .setup-history{background-color:var(--theme-surface);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] p,:root[data-theme="dark"] .muted,:root[data-theme="dark"] .intro,:root[data-theme="dark"] .setup-intro,:root[data-theme="dark"] .attempt-meta,:root[data-theme="dark"] .side-subtitle{color:var(--theme-muted)}
:root[data-theme="dark"] input,:root[data-theme="dark"] select,:root[data-theme="dark"] textarea{background:var(--theme-surface-2);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] table,:root[data-theme="dark"] th,:root[data-theme="dark"] td{border-color:var(--theme-line)}

.theme-toggle{display:inline-flex;align-items:center;justify-content:center;gap:7px;flex:0 0 auto;margin-left:12px;padding:8px 11px;border:1px solid #dce4d8;border-radius:9px;background:#f2f6ee;color:#285943;font:650 11px/1.2 "Segoe UI",Arial,sans-serif;white-space:nowrap;cursor:pointer;transition:background .16s,border-color .16s,transform .16s}
.theme-toggle:hover{transform:translateY(-1px);border-color:#8eaa88}
.theme-toggle-icon{font-size:14px;line-height:1}
.theme-toggle-floating{position:fixed;z-index:1000;right:18px;top:14px;margin:0;box-shadow:0 12px 34px #203c3410}
.home-head .theme-toggle{margin-left:auto}
.home-auth .theme-toggle{margin-left:4px}
:root[data-theme="dark"] .theme-toggle{background:#29362f;border-color:#46584b;color:#d7e6d1;box-shadow:var(--theme-shadow)}

:root[data-theme="dark"] .listening-taskbar{background:#171e1a;border-color:var(--theme-line)}
:root[data-theme="dark"] .listening-taskbar button,:root[data-theme="dark"] .listening-taskbar a{color:var(--theme-muted)}
:root[data-theme="dark"] .listening-taskbar button:hover,:root[data-theme="dark"] .listening-taskbar a:hover,:root[data-theme="dark"] .listening-taskbar .active{background:var(--theme-surface);border-color:var(--theme-line);color:var(--theme-text)}
:root[data-theme="dark"] .welcome-aside,:root[data-theme="dark"] .book-card,:root[data-theme="dark"] .feature-card,:root[data-theme="dark"] .search-box,:root[data-theme="dark"] .home-account-menu,:root[data-theme="dark"] .home-auth-dialog{background:var(--theme-surface);color:var(--theme-text);border-color:var(--theme-line);box-shadow:var(--theme-shadow)}
:root[data-theme="dark"] .book-card.full-book{background:linear-gradient(145deg,var(--theme-surface),var(--theme-surface-2));border-color:var(--theme-line)}
:root[data-theme="dark"] .test-link,:root[data-theme="dark"] .home-auth a,:root[data-theme="dark"] .home-auth button{background:var(--theme-surface-2);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] .home-auth .home-auth-primary,:root[data-theme="dark"] .dictation-cta,:root[data-theme="dark"] .welcome-dictation{background:#37634d;color:#f3f7ef;border-color:#4a765e}
:root[data-theme="dark"] .welcome-dictation small,:root[data-theme="dark"] .dictation-cta small{color:#d7e5d6}
:root[data-theme="dark"] .book-status,:root[data-theme="dark"] .history-type,:root[data-theme="dark"] .level{background:var(--theme-accent-soft);color:var(--theme-accent)}
:root[data-theme="dark"] .section-choice,:root[data-theme="dark"] .history-table,:root[data-theme="dark"] .history-table td,:root[data-theme="dark"] .score-cards article,:root[data-theme="dark"] .metric-grid article{background:var(--theme-surface-2);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] .history-table th{background:var(--theme-accent-soft);color:var(--theme-text)}
:root[data-theme="dark"] .history-result,:root[data-theme="dark"] .history-detail,:root[data-theme="dark"] .detail-link,:root[data-theme="dark"] .text-button{color:var(--theme-accent)}
:root[data-theme="dark"] .mode-tab{color:var(--theme-muted)}
:root[data-theme="dark"] .mode-tab.active,:root[data-theme="dark"] .section-choice:hover,:root[data-theme="dark"] .section-choice:has(input:checked){border-color:#83a778}
:root[data-theme="dark"] .answer-row,:root[data-theme="dark"] .part-bottom,:root[data-theme="dark"] .exercise-footer{border-color:var(--theme-line)}
:root[data-theme="dark"] .question-paper td,:root[data-theme="dark"] .question-paper th,:root[data-theme="dark"] .explanation-content td,:root[data-theme="dark"] .explanation-content th{background:var(--theme-surface-2);border-color:var(--theme-line);color:var(--theme-text)}
:root[data-theme="dark"] .instruction,:root[data-theme="dark"] .tip-box,:root[data-theme="dark"] .hints{background:var(--theme-accent-soft);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] .blank{background:var(--theme-surface-2);color:var(--theme-text);border-color:#809675}
:root[data-theme="dark"] .blank.correct{background:#263a2e;border-color:#7fa987}:root[data-theme="dark"] .blank.wrong{background:#3a2b27;border-color:#bd806d}
:root[data-theme="dark"] .progress-track,:root[data-theme="dark"] .audio-track{background:var(--theme-surface-2)}
:root[data-theme="dark"] .play-button{background:#344d3b;color:#e4e9e3}
:root[data-theme="dark"] .exam-sidebar{background:var(--theme-surface-2);border-color:var(--theme-line)}
:root[data-theme="dark"] .nav-grid button,:root[data-theme="dark"] .part-bottom button,:root[data-theme="dark"] .actions button,:root[data-theme="dark"] .explanation-tools button{background:var(--theme-surface-2);color:var(--theme-text);border-color:var(--theme-line)}
:root[data-theme="dark"] .nav-grid button.active,:root[data-theme="dark"] .nav-grid button.answered{background:#2a3c30;border-color:#78977b;color:#dcebd8}
:root[data-theme="dark"] .nav-grid button.review{background:#3a3025;border-color:#9a7448;color:#e7c99f}
:root[data-theme="dark"] .setup-page{background:var(--theme-page);color:var(--theme-text)}
:root[data-theme="dark"] .setup-page .site-head{background:var(--theme-surface);border-color:var(--theme-line)}
:root[data-theme="dark"] .setup-page .setup-history,:root[data-theme="dark"] .setup-page .history-table{background:var(--theme-surface-2)}
:root[data-theme="dark"] .setup-page .history-table th{background:#29352e;color:#d6e2d2}
:root[data-theme="dark"] .setup-page .history-table td{color:#c6d1c8}
:root[data-theme="dark"] .skill-nav{background:#222b27;border-color:var(--theme-line)}
:root[data-theme="dark"] .skill-tab{color:var(--theme-muted)}
:root[data-theme="dark"] .skill-tab.active{background:#3c654e;color:#f0f5ed;box-shadow:0 4px 12px #090e0b55}
:root[data-theme="dark"] .feature-card,:root[data-theme="dark"] .feature-card.selected{background:#202825;color:var(--theme-text);border-color:#3b4941;box-shadow:var(--theme-shadow)}
:root[data-theme="dark"] .feature-card.selected{background:linear-gradient(120deg,#29392f,#222b27);border-color:#789778}
:root[data-theme="dark"] .feature-card.selected .feature-select{color:#c0d7b6}
:root[data-theme="dark"] .welcome h1 em,:root[data-theme="dark"] .eyebrow{color:#a9c7a5}
:root[data-theme="dark"] .feature-icon,:root[data-theme="dark"] .coming-card .feature-icon{background:#304438;color:#c6d9bf}
:root[data-theme="dark"] .feature-card.selected .feature-icon{background:#496d54;color:#f1f5eb}
:root[data-theme="dark"] .step-hint i{background:#2e4033;color:#c5d8b8}
:root[data-theme="dark"] .home-account-trigger{background:#29372e!important;border-color:#405144!important;color:#d9e6d4!important}
:root[data-theme="dark"] .home-account-menu a,:root[data-theme="dark"] .home-account-menu button,:root[data-theme="dark"] .home-plan{color:var(--theme-text)}
:root[data-theme="dark"] .home-auth-dialog input{background:#18201c;color:var(--theme-text)}
@media(max-width:700px){.theme-toggle{margin-left:4px;padding:8px 9px;font-size:10px}.theme-toggle-floating{right:10px;top:10px}}