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button{text-align:start}.quiz-q{margin-block-end:18px}.quiz-q .stem{font-weight:650;margin-block-end:8px}.quiz-q .choices{display:flex;flex-direction:column;gap:6px}.quiz-q .choices button{font:inherit;text-align:start;padding:9px 14px;border-radius:var(--sk-radius);border:var(--control-edge) solid var(--grid);background:var(--surface);color:var(--ink);cursor:pointer}.quiz-q .choices button:hover:not(:disabled){border-color:var(--accent)}.quiz-q .choices button:disabled{cursor:default}.quiz-q .choices button.good{border-color:var(--good);background:var(--good-soft);color:var(--good-ink)}.quiz-q .choices button.bad{border-color:var(--crit);background:var(--crit-soft);color:var(--crit-ink)}.quiz-q .explain{margin-block-start:8px;color:var(--ink2);font-size:13.5px;border-inline-start:3px solid var(--accent);padding-inline-start:12px}.quiz-score{font-size:16px;font-weight:650;background:var(--accent-soft);color:var(--ink);border-radius:var(--sk-radius);padding:12px 16px}.quiz-score.perfect{background:var(--good-soft);color:var(--good-ink);font-weight:600}.quiz-q .stem .first-try{margin-inline-start:8px;font-size:12px;color:var(--good-ink);font-weight:600}.explain.nudge{color:var(--warn-ink)}.glossary-pop{position:fixed;z-index:40;width:360px;max-width:calc(100vw - 16px);background:var(--surface);color:var(--ink);border:var(--control-edge) solid var(--accent);border-radius:var(--sk-radius);padding:12px 16px;box-shadow:var(--sk-shadow-pop)}.glossary-pop b{font-family:var(--sk-font-display);font-size:16px;color:var(--accent-ink)}.glossary-pop p{margin:6px 0 0;font-size:13.5px}.explorer{background:var(--surface);border:var(--sk-border-w) solid var(--grid);border-radius:var(--sk-radius-l);box-shadow:var(--sk-shadow);clip-path:var(--sk-clip);padding:18px}.explorer form{display:flex;gap:8px}.explorer input{font:inherit;flex:1;min-width:0;padding:9px 14px;border-radius:var(--sk-radius);border:var(--control-edge) solid var(--grid);background:var(--surface-2);color:var(--ink)}.explorer input::placeholder{color:var(--muted)}.explorer input:focus-visible{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}.explorer button.go{font-size:15px;padding:9px 18px;border-radius:var(--sk-radius);border:none;background:var(--accent);color:var(--on-accent);box-shadow:0 var(--sk-press) 0 var(--accent-deep),var(--sk-glow);clip-path:var(--sk-clip);font-weight:700;cursor:pointer}.explorer button.go:disabled{opacity:.5;cursor:default;box-shadow:none}.explorer .answer{margin-block-start:14px;white-space:pre-wrap}.explorer .hint{color:var(--muted);font-size:12.5px;margin-block-start:10px}.explorer .offline{color:var(--muted);font-size:13.5px}.footer-note{color:var(--muted);font-size:12.5px;text-align:center;margin-block-start:48px}header.app .glossary-link{margin-inline-start:auto;font-weight:650}.glossary-list{margin:0}.glossary-row{display:grid;grid-template-columns:minmax(150px,210px) 1fr;gap:14px;padding:10px 4px;border-block-end:1px solid var(--grid)}.glossary-row dt{font-family:var(--sk-font-display);font-weight:700;font-size:15.5px;color:var(--accent-ink)}.glossary-row dt .stands-for{display:block;font-family:var(--sk-font-body);font-weight:400;font-size:12px;color:var(--muted)}.glossary-row dd{margin:0;color:var(--ink2);font-size:14px}@media (max-width: 560px){.glossary-row{grid-template-columns:1fr;gap:2px}}.vg-intro{color:var(--ink2);margin:0 0 14px}.vg-controls{display:flex;gap:14px;align-items:center;flex-wrap:wrap;margin-block-end:10px}.tabs{display:flex;flex-wrap:wrap;gap:6px}.tabs button{font:inherit;font-size:13.5px;font-weight:700;padding:6px 14px;border-radius:999px;border:var(--sk-border-w) solid var(--axis);background:var(--surface);color:var(--ink2);cursor:pointer}.tabs button[aria-selected=true]{background:var(--accent);border-color:var(--accent);color:var(--on-accent)}.vg-search{font:inherit;padding:8px 12px;border-radius:var(--sk-radius-s);border:var(--sk-border-w) solid var(--axis);background:var(--surface);color:var(--ink);min-width:min(240px,100%)}.vg-search::placeholder{color:var(--muted)}.vg-status{color:var(--muted);font-size:13px;margin:4px 0 10px}.vg-sense{display:grid;grid-template-columns:auto 1fr;column-gap:6px;row-gap:2px;margin-block-end:8px}.vg-sense:last-child{margin-block-end:0}.vg-n{color:var(--accent-ink);grid-row:1 / span 3}.vg-sense>:not(.vg-n){grid-column:2}.vg-def{color:var(--ink)}.vg-ex{color:var(--ink2)}.vg-used{font-size:12px;color:var(--muted)}.vg-derivation{display:block;font-size:12.5px;color:var(--warn-ink);font-style:italic;margin-block-end:6px}.gate-note{color:var(--muted);font-size:13px;margin:0 0 10px}.locked-note{color:var(--muted);font-size:13px}.locked-note.done{color:var(--good-ink);font-weight:600}.help-bar{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin:8px 0 4px;padding:10px 12px;border:1.5px dashed color-mix(in srgb,var(--accent) 45%,transparent);border-radius:var(--sk-radius);background:var(--accent-soft)}.help-label{font-weight:650;color:var(--accent-ink);font-size:13.5px}button.chip.help-chip{border-color:var(--accent);color:var(--accent-ink)}.help-status,.help-muted{font-size:12.5px;color:var(--ink2)}.practice-with-help{margin-block-end:14px}.practice-with-help .help-bar{margin-block-start:-6px}.daily-card{display:flex;align-items:center;gap:20px;background:var(--surface);border:var(--sk-border-w) solid var(--grid);border-radius:var(--sk-radius-l);box-shadow:var(--sk-shadow);clip-path:var(--sk-clip);padding:20px 24px;margin:20px 0 30px;flex-wrap:wrap}.daily-body{flex:1;min-width:min(240px,100%)}.daily-body h2{margin:0 0 4px;font-size:22px}.daily-body p{margin:0 0 12px;color:var(--ink2);font-size:14px}.goal-ring .ring-big{font-size:26px;font-weight:800;fill:var(--ink)}.goal-ring .ring-small{font-size:11px;fill:var(--muted);font-weight:700;font-family:var(--sk-font-body)}.streak{display:flex;flex-direction:column;align-items:center;min-width:64px}.streak .flame{font-size:30px}.streak b{font-size:22px;color:var(--warn-ink)}.streak-label{font-size:11px;color:var(--muted);font-weight:700}.duo-btn{font-size:15px;font-weight:800;padding:12px 22px;border-radius:var(--sk-radius);border:0;color:var(--on-accent);background:var(--accent);box-shadow:0 var(--sk-press) 0 var(--accent-deep),var(--sk-glow);clip-path:var(--sk-clip);cursor:pointer;text-align:start}.duo-btn:active{transform:translateY(calc(var(--sk-press) * .6));box-shadow:0 calc(var(--sk-press) * .4) 0 var(--accent-deep)}.home-heading{font-size:15px;color:var(--muted);margin:26px 0 12px}.tile-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(260px,100%),1fr));gap:14px}.menu-tile{display:flex;align-items:center;gap:16px;text-align:start;font:inherit;color:var(--ink);background:var(--surface);border:var(--sk-border-w) solid var(--grid);border-radius:var(--sk-radius-l);box-shadow:var(--sk-shadow);clip-path:var(--sk-clip);padding:16px;cursor:pointer;transition:transform .12s,border-color .12s}.menu-tile:hover{transform:translateY(-2px);border-color:var(--axis)}.menu-tile:active{transform:translateY(2px)}.menu-tile .tile-icon{flex:0 0 58px;height:58px;border-radius:var(--sk-radius);display:grid;place-items:center;font-size:28px;background:var(--hue);box-shadow:inset 0 calc(-1 * var(--sk-press)) 0 var(--hue-deep)}.menu-tile.current{border-color:var(--hue)}.menu-tile .tile-body{flex:1;display:flex;flex-direction:column;gap:2px}.menu-tile .tile-body b{font-size:16px;font-weight:800}.menu-tile .tile-sub{color:var(--ink2);font-size:13px}.menu-tile .tile-progress{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--muted);font-weight:700;margin-block-start:4px}.menu-tile .tile-bar{flex:1;height:8px;border-radius:999px;background:var(--ring-track);overflow:hidden}.menu-tile .tile-bar span{display:block;height:100%;border-radius:999px;background:var(--hue-deep)}.unit-banner{display:flex;align-items:center;justify-content:space-between;gap:16px;color:var(--hue-ink);background:var(--hue-soft);border:var(--sk-border-w) solid var(--hue);border-radius:var(--sk-radius-l);box-shadow:0 var(--sk-press) 0 var(--hue-deep);clip-path:var(--sk-clip);padding:20px 24px;margin:18px 0 8px}.unit-banner h2{margin:2px 0;font-size:24px}.unit-banner p{margin:0;font-size:13.5px}.unit-kicker{font-size:12px;font-weight:800}.unit-emoji{font-size:42px}.path{display:flex;flex-direction:column;align-items:center;padding:26px 0 10px}.path-row{--wave-dir: 1;--wave-scale: 1;display:flex;flex-direction:column;align-items:center;margin:14px 0;position:relative;max-width:340px;text-align:center;transform:translate(calc(var(--wave, 0px) * var(--wave-dir) * var(--wave-scale)))}[dir=rtl] .path-row{--wave-dir: -1}@media (max-width: 560px){.path-row{--wave-scale: .35}}.path-node{--node: var(--grid);--node-deep: var(--axis);width:76px;height:76px;border-radius:50%;border:2px solid var(--node-deep);background:var(--node);box-shadow:0 var(--sk-press) 0 var(--node-deep);font-size:30px;cursor:pointer;display:grid;place-items:center;color:var(--ink);transition:transform .12s}.path-node:active:not(:disabled){transform:translateY(3px)}.path-node.locked{cursor:not-allowed;filter:grayscale(1)}.path-node.done{--node: var(--sk-gold-soft);--node-deep: var(--sk-gold-deep);border-color:var(--sk-gold);color:var(--sk-gold-ink)}.path-node.done.gold{font-size:34px}.path-node.current{--node: var(--hue);--node-deep: var(--hue-deep);animation:node-pulse 1.6s ease-in-out infinite}@keyframes node-pulse{0%,to{box-shadow:0 var(--sk-press) 0 var(--node-deep),0 0 color-mix(in srgb,var(--sk-gold) 55%,transparent)}60%{box-shadow:0 var(--sk-press) 0 var(--node-deep),0 0 0 14px transparent}}.start-bubble{position:absolute;top:-34px;background:var(--surface);color:var(--accent-ink);border:2px solid var(--grid);border-radius:var(--sk-radius);padding:4px 12px;font-size:12px;font-weight:800;animation:bubble-bob 1.4s ease-in-out infinite;z-index:2}.start-bubble:after{content:"";position:absolute;inset-inline:0;margin-inline:auto;bottom:-6px;transform:rotate(45deg);width:10px;height:10px;background:var(--surface);border-right:2px solid var(--grid);border-bottom:2px solid var(--grid)}@keyframes bubble-bob{0%,to{transform:translateY(0)}50%{transform:translateY(-5px)}}.path-label{margin-block-start:8px}.path-label b{display:block;font-size:14.5px}.path-label span{color:var(--ink2);font-size:12.5px}.path-label.dim{opacity:.6}.path-row.trophy .path-node{font-size:34px}[hidden]{display:none!important}.step-bar{display:flex;gap:6px;background:var(--surface);border:var(--sk-border-w) solid var(--grid);border-radius:var(--sk-radius-l);box-shadow:var(--sk-shadow);padding:6px;margin:6px 0 18px;position:sticky;top:58px;z-index:4;overflow-x:auto}.step-tab{flex:1;min-width:74px;display:flex;flex-direction:column;align-items:center;gap:1px;font-size:12.5px;font-weight:800;color:var(--ink2);border:0;background:none;border-radius:var(--sk-radius);padding:7px 10px 6px;cursor:pointer}.step-tab .step-icon{font-size:17px}.step-tab.past{color:var(--muted)}.step-tab:hover{background:var(--surface-2)}.step-tab.active{background:var(--accent);color:var(--on-accent);box-shadow:0 min(3px,var(--sk-press)) 0 var(--accent-deep)}.step-continue{display:flex;justify-content:center;margin-block-start:22px}.step-continue.split-ends{justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}@media (max-width: 560px){header.app{position:static;padding-inline:16px}.step-bar{top:6px}.step-tab{min-width:58px;padding-inline:4px}}.host-splash{display:flex;align-items:center;justify-content:center;min-height:60vh;font-size:1.1rem;color:var(--ink2)}.host-banner{padding:10px 16px;background:var(--sk-gold-soft);color:var(--sk-gold-ink);border-block-end:var(--sk-border-w) solid var(--sk-gold-deep);font-size:.9rem}.host-banner a{color:inherit;font-weight:700;margin-inline-start:6px}.student-pill{margin-inline-start:auto;color:var(--ink2);font-size:.9rem}.back-portal{font-weight:700}