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input,.blank-field select{padding:13px 11px;font-size:.73rem}.result{padding:16px 14px}.result h3{font-size:.78rem}.result>p{font-size:.71rem}.result details{font-size:.65rem}.result details pre{font-size:.64rem;padding:10px}.account-panel{padding:33px 20px}.account-panel>p:not(.panel-footnote){font-size:.77rem}.account-details>div{font-size:.72rem}.account-panel .button{font-size:.75rem}.page-subtitle{font-size:.78rem;line-height:1.8}.toast{font-size:.71rem;padding:13px 16px}.login-page{display:flex;flex-direction:column;min-height:100svh!important}.login-intro{padding:26px 25px 26px;min-height:0}.login-message{padding:30px 0 0;margin:0}.login-message h1{font-size:2rem;margin:15px 0 14px;line-height:1.17}.login-message p{font-size:.74rem;line-height:1.8;margin-bottom:0;max-width:295px;color:#a89aba}.login-message p br{display:none}.login-eyebrow{font-size:.47rem;letter-spacing:.11em}.login-code,.login-footer{display:none}.login-intro .brand-mark{width:33px;height:33px;border-radius:10px;font-size:25px}.login-intro .brand-name{font-size:17px}.login-intro .brand-name>span{font-size:10px}.login-form-wrap{padding:32px 25px 36px;flex:1}.login-form-inner{max-width:390px}.welcome-symbol{display:none}.login-form-inner .eyebrow{font-size:.51rem}.login-form-inner h2{font-size:1.55rem}.login-subtitle{font-size:.76rem;margin:10px 0 25px}#login-form{gap:17px}#login-form label{font-size:.72rem}#login-form input{font-size:16px;padding:13px}#login-form .button{font-size:.8rem}.invite-note{margin-top:24px;padding-top:20px}.invite-note p{font-size:.65rem}.copy-dialog{padding:22px 18px}.copy-dialog h2{font-size:1.1rem}.copy-dialog p{font-size:.73rem}.copy-dialog textarea{font-size:.68rem}.copy-dialog .button{font-size:.76rem}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;transition:none!important;animation-duration:1.5s!important}.spinner{animation-duration:2s!important}}

/* Keep the account reachable in short desktop windows. */
.sidebar{overflow-y:auto;scrollbar-width:thin}.sidebar>.brand,.sidebar>nav,.sidebar-user{flex-shrink:0}
@media(max-height:760px) and (min-width:761px){.sidebar-note{padding-top:30px;margin-bottom:20px}.sidebar-label{margin-top:33px}.sidebar-note p{display:none}}


/* Theme controls stay reachable on login, desktop, and narrow phones. */
:root { color-scheme: light; --text-secondary:#6f657c; --text-caption:#786b86; --field:#fbf9fe; }
:root[data-theme="dark"] {
  color-scheme: dark; --bg:#17151f; --surface:#211e2b; --ink:#f1edf7;
  --muted:#b5acc3; --line:#393343; --purple:#a88af3; --purple-dark:#bea5ff;
  --purple-soft:#332943; --sidebar:#1c1925; --shadow:0 4px 24px #00000012;
  --text-secondary:#c2b6d1; --text-caption:#ac9ebd; --field:#292331;
}
.theme-toggle { display:inline-flex; align-items:center; justify-content:center; flex-shrink:0;
  width:42px; height:42px; border:1px solid var(--line); border-radius:12px;
  background:var(--surface); color:var(--text-secondary); }
.theme-toggle:hover { border-color:var(--purple); color:var(--purple); }
.theme-toggle .icon { width:20px; height:20px; }
.login-form-wrap { position:relative; }
.login-theme { position:absolute; top:24px; right:24px; }
.account-theme { display:flex; align-items:center; justify-content:space-between; gap:15px; padding:13px 0; font-size:.79rem; }
.account-theme select { max-width:175px; min-height:42px; padding:8px 12px; border:1px solid var(--line);
  border-radius:8px; background:var(--field); color:var(--ink); }
/* Keep small explanatory text legible in both themes. */
.topic-description,.task-row-copy small,.stat-label,.overall-progress>span,
.help-intro,.help-link small,.copy-note,.panel-footnote,.history-list small,
.progress-topic small,.task-tip p,.draft-status,.login-subtitle,.invite-note,
.account-panel>p:not(.panel-footnote),.account-details span,.quiet-note,.page-footer,
.login-form-inner #login-form label { color:var(--text-secondary); }
.eyebrow,.small-caption,.topbar-label,.runtime-pill,.lesson-meta,.progress-topic-title>span,
.task-breadcrumb,.task-tip>span,.editor-foot,.editor-bar,.code-label { color:var(--text-caption); }
.task-prompt { color:var(--text-secondary); }
.help-link strong,.help-link,.task-breadcrumb a,.text-button { color:#73538c; }
.solution-box>p { color:#746181; }
:root[data-theme="dark"] .topbar { background:var(--bg); border-color:var(--line); }
:root[data-theme="dark"] .panel { background:var(--surface); }
:root[data-theme="dark"] .hero { background:#30263f; border-color:#49375c; }
:root[data-theme="dark"] .hero-label,:root[data-theme="dark"] .hero p { color:#d1c0e7; }
:root[data-theme="dark"] .primary { color:#20162e; }
:root[data-theme="dark"] .secondary { background:#2b2536; border-color:#4b3e5c; color:#e7d8fa; }
:root[data-theme="dark"] .secondary:hover:not(:disabled) { background:#382d46; border-color:#80649f; }
:root[data-theme="dark"] .topbar-avatar,:root[data-theme="dark"] .avatar,:root[data-theme="dark"] .account-avatar {
  background:#443453; color:#e2c9ff; }
:root[data-theme="dark"] .purple,:root[data-theme="dark"] .tone-0 { background:#392e4b; color:#c2a4ff; }
:root[data-theme="dark"] .lime,:root[data-theme="dark"] .tone-1 { background:#2e3926; color:#c9df94; }
:root[data-theme="dark"] .tone-2 { background:#263447; color:#a1c5e7; }
:root[data-theme="dark"] .peach,:root[data-theme="dark"] .tone-3 { background:#422f27; color:#e8b58e; }
:root[data-theme="dark"] .topic-count,:root[data-theme="dark"] .task-number,:root[data-theme="dark"] .choice-letter {
  background:#302939; color:#c4b1d9; }
:root[data-theme="dark"] .task-number.done,:root[data-theme="dark"] .task-status.solved {
  background:#303e24; color:#d0e9a3; }
:root[data-theme="dark"] .task-status.assisted { background:#3e2e53; color:#d8b9ff; }
:root[data-theme="dark"] .stat-number small { color:#b1a5c0; }
:root[data-theme="dark"] .lesson,:root[data-theme="dark"] .history-list li+li,
:root[data-theme="dark"] .panel-footnote,:root[data-theme="dark"] .assistance-note,
:root[data-theme="dark"] .help-link,:root[data-theme="dark"] .invite-note { border-color:var(--line); }
:root[data-theme="dark"] .progress-track,:root[data-theme="dark"] .help-divider { background:#3b3347; }
:root[data-theme="dark"] .progress-track::-webkit-progress-bar { background:#3b3347; }
:root[data-theme="dark"] .progress-track::-webkit-progress-value { background:#b194ef; }
:root[data-theme="dark"] .progress-track::-moz-progress-bar { background:#b194ef; }
:root[data-theme="dark"] .pill { background:#30263d; border-color:#564265; color:#d5bde9; }
:root[data-theme="dark"] .difficulty { background:#2f3b24; color:#d5e7ae; }
:root[data-theme="dark"] .difficulty.medium { background:#463725; color:#efcea2; }
:root[data-theme="dark"] .difficulty.hard,:root[data-theme="dark"] .difficulty.very_hard { background:#3c2e4e; color:#dfc1ff; }
:root[data-theme="dark"] .step-badge { background:#3b2b4c; color:#d6b8f5; }
:root[data-theme="dark"] .empty-state,:root[data-theme="dark"] .empty-state h3 { color:var(--text-secondary); }
:root[data-theme="dark"] .time-label,:root[data-theme="dark"] .submit-note { color:#b4a5c4; }
:root[data-theme="dark"] .code-label,:root[data-theme="dark"] .editor-bar { background:#2d2539; border-color:var(--line); }
:root[data-theme="dark"] .code-block,:root[data-theme="dark"] .code-editor,
:root[data-theme="dark"] .solution-box .code-block,:root[data-theme="dark"] .order-block {
  background:#1c1924; border-color:#43364f; color:#dbc8ef; }
:root[data-theme="dark"] .code-input,:root[data-theme="dark"] .order-block pre { color:#e1cfef; }
:root[data-theme="dark"] .editor-foot { border-color:var(--line); }
:root[data-theme="dark"] .editor-bar i { background:#6c5b7c; }
:root[data-theme="dark"] .choice { border-color:#4b3d59; }
:root[data-theme="dark"] .choice:hover { background:#30263b; border-color:#8d6fac; }
:root[data-theme="dark"] .choice.selected { background:#392c4b; border-color:#b695ed; }
:root[data-theme="dark"] .choice.selected .choice-letter { background:#b497dd; color:#21162e; }
:root[data-theme="dark"] .choice-check { color:#c4a2ed; }
:root[data-theme="dark"] .order-index,:root[data-theme="dark"] .blank-field>span { color:#c5afd8; }
:root[data-theme="dark"] .icon-button { background:#33283f; color:#d5b9ee; border-color:#51405e; }
:root[data-theme="dark"] .blank-index { background:#44314f; color:#d9b9ec; }
:root[data-theme="dark"] .blank-field input,:root[data-theme="dark"] .blank-field select,
:root[data-theme="dark"] #login-form input { background:var(--field); border-color:#51415e; color:#e8d9f3; }
:root[data-theme="dark"] #login-form input::placeholder { color:#b7a5c5; }
:root[data-theme="dark"] .help-link strong,:root[data-theme="dark"] .help-link,
:root[data-theme="dark"] .text-button,:root[data-theme="dark"] .task-breadcrumb a { color:#ceadee; }
:root[data-theme="dark"] .help-icon { background:#3e3927; color:#e0d398; }
:root[data-theme="dark"] .hint-box { background:#393022; border-color:#5b4b31; }
:root[data-theme="dark"] .hint-box>strong,:root[data-theme="dark"] .hint-box p { color:#e7d1a5; }
:root[data-theme="dark"] .solution-box { background:#302439; border-color:#584267; }
:root[data-theme="dark"] .solution-box h3,:root[data-theme="dark"] .solution-box>p,
:root[data-theme="dark"] .assistance-note p { color:#d5bee6; }
:root[data-theme="dark"] .result { background:#33263e; border-color:#594366; color:#e1c9f0; }
:root[data-theme="dark"] .result.success { background:#2b3822; border-color:#4b6337; color:#d1e9b1; }
:root[data-theme="dark"] .result.incorrect,:root[data-theme="dark"] .notice { background:#3c2d23; border-color:#665039; color:#edcda7; }
:root[data-theme="dark"] .result.neutral { background:#302a3a; border-color:#51465f; color:#d7c8e5; }
:root[data-theme="dark"] .result-next { border-color:#4f633e; }
:root[data-theme="dark"] .result details pre { background:#18151e99; }
:root[data-theme="dark"] .welcome-symbol { background:#382a47; color:#d0aeee; }
:root[data-theme="dark"] .login-error,:root[data-theme="dark"] .draft-status.failed { color:#efb591; }
:root[data-theme="dark"] .mobile-nav { background:#211c2b; border-color:var(--line); }
:root[data-theme="dark"] .mobile-nav .nav-link { color:#b9a4cd; }
:root[data-theme="dark"] .mobile-nav .nav-link.active,
:root[data-theme="dark"] .mobile-nav .nav-link.active .icon { color:#d4b5ff; }
:root[data-theme="dark"] .mobile-brand .brand-name { color:#f1e6ff; }
:root[data-theme="dark"] .mobile-brand .brand-name>span { color:#bda5d4; }
:root[data-theme="dark"] .copy-dialog { background:var(--surface); border-color:#64506e; color:var(--ink); }
:root[data-theme="dark"] .copy-dialog p { color:var(--text-secondary); }
:root[data-theme="dark"] .copy-dialog textarea { background:var(--field); border-color:#574562; color:#e0c8ed; }
@media(max-width:560px) {
  .topbar-right { gap:10px; }
  .theme-toggle { width:38px; height:38px; border-radius:11px; }
  .login-theme { top:18px; right:18px; }
  .login-form-wrap { padding-top:62px; }
  .account-theme { align-items:flex-start; flex-direction:column; gap:9px; }
  .account-theme select { max-width:none; width:100%; }
}

@media(max-width:560px) { .code-input,.blank-field input,.blank-field select { font-size:16px; } }

/* Curriculum: compact catalogue plus a focused reading view for each lesson. */
.catalog-counts { margin:9px 0 0; color:var(--text-secondary); font-size:.74rem; line-height:1.65; }
.catalog-controls { display:grid; grid-template-columns:minmax(0,1.25fr) minmax(0,1fr); gap:15px; margin-bottom:13px; }
.catalog-controls label { display:grid; gap:8px; color:var(--text-secondary); font-size:.73rem; min-width:0; }
.catalog-controls input,.catalog-controls select { width:100%; min-width:0; border:1px solid var(--line);
  border-radius:10px; background:var(--surface); color:var(--ink); padding:13px 14px; min-height:46px; font-size:.84rem; }
.catalog-controls input::placeholder { color:var(--text-caption); }
.catalog-results-row { display:flex; align-items:center; justify-content:space-between; gap:15px; margin-bottom:20px; }
.catalog-results-row>p { margin:0; color:var(--text-secondary); font-size:.68rem; line-height:1.65; }
.catalog-results-row .text-button { flex-shrink:0; font-size:.7rem; padding:7px 0; }
.catalog-results-row [hidden] { display:none; }
.catalog-empty { grid-column:1/-1; padding:30px; }
.catalog-empty h3 { margin-bottom:10px; }
.catalog-empty p { color:var(--text-secondary); margin-bottom:0; }
.lesson-open { display:flex; align-items:center; justify-content:space-between; gap:10px; font-size:.73rem;
  line-height:1.6; color:#73538c; background:#f4eefb; border-radius:8px; padding:12px; margin-bottom:7px; }
.lesson-open:hover { background:#ebe0f8; }
.lesson-page-heading { max-width:960px; }
.lesson-page-layout { display:grid; grid-template-columns:minmax(0,1.3fr) minmax(260px,.8fr); gap:22px; align-items:start; }
.lesson-notes.panel { padding:0; }
.lesson-notes>summary { display:flex; align-items:center; justify-content:space-between; list-style:none;
  gap:15px; padding:23px 25px; font-weight:650; font-size:1rem; cursor:pointer; border-radius:var(--radius); }
.lesson-notes>summary::-webkit-details-marker { display:none; }
.notes-toggle { color:var(--purple); font-size:1.25rem; line-height:1; }
.lesson-notes[open] .notes-toggle { transform:rotate(180deg); }
.lesson-notes-body { padding:0 25px 25px; }
.lesson-introduction { white-space:pre-wrap; overflow-wrap:anywhere; color:var(--text-secondary); font-size:.9rem; line-height:1.9; }
.learning-objectives { border-top:1px solid var(--line); margin-top:22px; padding-top:20px; }
.learning-objectives h2 { font-size:.9rem; letter-spacing:-.02em; }
.learning-objectives ul { padding-left:19px; margin:12px 0 0; color:var(--text-secondary); font-size:.83rem; line-height:1.8; }
.learning-objectives li+li { margin-top:7px; }
.lesson-doc-link { display:inline-flex; align-items:center; gap:10px; font-size:.8rem; color:#73538c; line-height:1.7; margin-top:24px; }
.lesson-reading-note { border-top:1px solid var(--line); padding-top:16px; margin:20px 0 0; font-size:.7rem; line-height:1.8; color:var(--text-caption); }
.lesson-task-panel .panel-heading { margin-bottom:18px; }
.lesson-task-panel .task-row { padding:15px 0; }
.lesson-task-panel .task-list li+li { border-top:1px solid var(--line); }
.lesson-continue { width:100%; margin-bottom:14px; font-size:.8rem; }
:root[data-theme="dark"] .lesson-open { background:#35283f; color:#d7b9f2; }
:root[data-theme="dark"] .lesson-open:hover { background:#44304f; }
:root[data-theme="dark"] .lesson-doc-link { color:#d6b9f5; }
@media(max-width:1000px) { .lesson-page-layout { grid-template-columns:1fr; } }
@media(max-width:560px) {
  .catalog-counts { font-size:.65rem; }
  .catalog-controls { grid-template-columns:1fr; gap:13px; margin-bottom:10px; }
  .catalog-controls label { font-size:.74rem; }
  .catalog-controls input,.catalog-controls select { font-size:16px; padding:12px; }
  .catalog-results-row { align-items:flex-start; gap:12px; }
  .catalog-results-row>p { font-size:.62rem; max-width:195px; }
  .catalog-results-row .text-button { font-size:.65rem; padding:0; max-width:85px; text-align:right; }
  .lesson-open { font-size:.76rem; padding:13px; }
  .lesson-notes>summary { padding:21px; font-size:1rem; }
  .lesson-notes-body { padding:0 21px 22px; }
  .lesson-introduction { font-size:.9rem; line-height:1.85; }
  .lesson-page-layout { gap:17px; }
  .lesson-task-panel { padding:23px 21px; }
  .lesson-task-panel .task-row-copy strong { font-size:.85rem; }
  .lesson-task-panel .task-row-copy small { font-size:.7rem; }
  .lesson-doc-link { font-size:.82rem; }
  .lesson-reading-note { font-size:.73rem; }
}

.curriculum-release { margin:0 0 28px; border:1px solid #dfdfca; background:#f1f3e8; color:#566443; border-radius:12px; padding:17px 20px; font-size:.79rem; line-height:1.7; }
.curriculum-release strong { font-weight:600; }
.curriculum-release p { margin:4px 0 0; font-size:.75rem; }
:root[data-theme="dark"] .curriculum-release { background:#293124; border-color:#455239; color:#d0dcba; }
@media(max-width:560px) { .curriculum-release { font-size:.78rem; padding:17px; } .curriculum-release p { font-size:.73rem; } }
/* Long API identifiers and lesson titles must wrap even on 320px displays. */
.lesson summary>span:first-child { min-width:0; overflow-wrap:anywhere; }
.learning-objectives li,.lesson-page-heading h1 { overflow-wrap:anywhere; }