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0}.feature-group+.feature-group{margin-top:3.2rem}.group-head{display:flex;align-items:center;gap:.9rem;font-size:1rem;margin:0 0 1.3rem}.group-head:after{content:"";flex:1;height:2px;background:var(--ink);opacity:.15}.group-badge{background:var(--yellow);border:2px solid var(--ink);border-radius:999px;box-shadow:3px 3px 0 var(--ink);padding:.45rem 1.1rem}.group-teach .group-badge{background:var(--ink);color:var(--card)}.group-sub{color:var(--muted);font-size:.95rem;margin:-.7rem 0 1.4rem}.feature-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:1.4rem}.card{background:var(--card);border:2px solid var(--ink);border-radius:var(--r);box-shadow:var(--shadow);padding:1.4rem 1.5rem}.card h3,.card h4{font-size:1.15rem;margin:.4em 0}.card p{margin:0;color:var(--muted)}.card-icon{font-size:1.8rem;line-height:1;display:inline-block}.step-list{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:1.4rem;counter-reset:step}.step{position:relative;padding-top:2.2rem}.step-num{position:absolute;top:-1.1rem;left:1.2rem;width:2.4rem;height:2.4rem;display:grid;place-items:center;font-family:var(--font-head);font-size:1.15rem;font-weight:700;background:var(--yellow);border:2px solid var(--ink);border-radius:50%;box-shadow:3px 3px 0 var(--ink)}.levels{padding:clamp(2.5rem,7vw,4.5rem) 0}.levels-sub{text-align:center;color:var(--muted);max-width:38rem;margin:-1.6em auto 1.8em}.level-tabs{display:flex;flex-wrap:wrap;justify-content:center;gap:.8rem;margin-bottom:1.6rem}.level-tab{font-family:var(--font-head);font-size:.95rem;color:var(--ink);background:var(--card);border:2px solid var(--ink);border-radius:999px;box-shadow:3px 3px 0 var(--ink);padding:.5rem 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var(--ink)}.mc-question{font-family:var(--font-head);font-size:1.05rem;font-weight:700;margin:0 0 1rem}.answer-row{display:flex;flex-wrap:wrap;gap:.7rem}.typed-input,.cloze-gap input{font:inherit;color:var(--ink);background:var(--bg);border:2px solid var(--ink);border-radius:6px;box-shadow:2px 2px 0 var(--ink) inset;padding:.6rem .9rem}.typed-input{flex:1 1 12rem;min-width:0}.typed-input:focus-visible,.cloze-gap input:focus-visible{outline:3px solid var(--accent);outline-offset:2px}.typed-input.is-correct,.cloze-gap input.is-correct{background:var(--yellow)}.typed-input.is-wrong,.cloze-gap input.is-wrong{background:var(--accent);color:var(--card)}.check-btn{font-family:var(--font-head);font-size:.95rem;color:var(--ink);background:var(--yellow);border:2px solid var(--ink);border-radius:6px;box-shadow:2px 2px 0 var(--ink);padding:.6rem 1.2rem;cursor:pointer}.check-btn:disabled{background:var(--bg);cursor:default;box-shadow:none}.cloze-text{margin:0 0 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1.7rem}.duel-head{display:flex;align-items:center;justify-content:space-between;gap:.8rem;font-family:var(--font-head);font-weight:700;margin-bottom:1rem}.duel-vs{background:var(--yellow);border:2px solid var(--ink);border-radius:999px;padding:.1rem .6rem;font-size:.8rem;box-shadow:2px 2px 0 var(--ink)}.duel-status{display:block;font-family:var(--font-body);font-weight:400;font-size:.75rem;color:var(--muted);text-align:right;min-height:1.1em}.duel-timer{height:.9rem;border:2px solid var(--ink);border-radius:999px;background:var(--bg);overflow:hidden;margin-bottom:1.2rem}.duel-timer-bar{height:100%;width:100%;background:var(--yellow);transition:width .1s linear}.duel-timer-bar.low{background:var(--accent)}.duel-q{font-family:var(--font-head);font-size:1.25rem;font-weight:700;margin:0 0 1.1rem}.duel-options{display:grid;grid-template-columns:1fr 1fr;gap:.8rem}@media(max-width:540px){.duel-options{grid-template-columns:1fr}.level-card{min-height:0}}.duel-option{font-family:var(--font-head);font-size:.98rem;text-align:left;color:var(--ink);background:var(--bg);border:2px solid var(--ink);border-radius:var(--r);box-shadow:3px 3px 0 var(--ink);padding:.8rem 1rem;cursor:pointer;transition:transform .1s ease,box-shadow .1s ease}.duel-option:hover:not(:disabled){transform:translate(-2px,-2px);box-shadow:5px 5px 0 var(--ink)}.duel-option:disabled{cursor:default}.duel-option.is-correct{background:var(--yellow)}.duel-option.is-wrong{background:var(--accent);color:var(--card)}.duel-option:disabled:not(.is-correct):not(.is-wrong){opacity:.55}.duel-result{font-family:var(--font-head);font-weight:700;margin:1.2rem 0 0}.duel-actions{display:flex;flex-wrap:wrap;gap:.9rem;margin-top:1.2rem}.faq{padding:clamp(2.5rem,7vw,4.5rem) 0}.faq-list{max-width:720px;margin:0 auto;display:grid;gap:1rem}.faq-item{background:var(--card);border:2px solid var(--ink);border-radius:var(--r);box-shadow:var(--shadow)}.faq-item summary{list-style:none;cursor:pointer;font-family:var(--font-head);font-size:1.08rem;font-weight:700;padding:1.1rem 3rem 1.1rem 1.4rem;position:relative}.faq-item summary::-webkit-details-marker{display:none}.faq-item summary:after{content:"+";position:absolute;right:1.3rem;top:50%;transform:translateY(-50%);font-size:1.5rem}.faq-item[open] summary:after{content:"−"}.faq-link{margin-top:.6em}.faq-item p{margin:0;padding:0 1.4rem 1.3rem;color:var(--muted)}.cta{padding:clamp(2.5rem,7vw,4.5rem) 0 clamp(3.5rem,8vw,5.5rem)}.cta-box{background:var(--yellow);border:2px solid var(--ink);border-radius:var(--r);box-shadow:6px 6px 0 var(--ink);padding:clamp(2rem,6vw,3.5rem);text-align:center}.cta-box h2{margin-bottom:.4em}.cta-box p{margin-bottom:1.6em;color:var(--ink)}@media(max-width:480px){.chip-1{top:-6%;left:0}.chip-2{bottom:-8%;right:0}.chip-3{bottom:-8%;left:0}.flip-hint{top:calc(100% + 2.8rem)}}@media(max-width:400px){.hero{padding-bottom:6.5rem}.chip-3{bottom:-32%}.flip-hint{top:calc(100% + 6rem)}}@media(max-width:820px){.hero-grid{grid-template-columns:1fr;gap:3.5rem;text-align:center}.lead{margin-inline:auto}.hero-actions{justify-content:center}}@media(prefers-reduced-motion:reduce){.flip-inner{transition:none}}