:root{--bg: oklch(97% .012 90);--surface: #ffffff;--ink: oklch(22% .02 280);--ink-soft: oklch(48% .02 280);--ink-faint: oklch(65% .015 90);--accent: oklch(58% .19 300);--accent-strong: oklch(50% .2 300);--accent-soft: oklch(94% .03 300);--success: oklch(58% .14 150);--success-bg: oklch(94% .05 150);--danger: oklch(56% .15 25);--danger-bg: oklch(95% .035 25);--warn-ink: oklch(48% .13 80);--warn-bg: oklch(93% .06 80);--border: oklch(91% .008 90);font-family:Inter,system-ui,-apple-system,Segoe UI,sans-serif}@keyframes popCorrect{0%{transform:scale(1)}45%{transform:scale(1.035)}to{transform:scale(1)}}@keyframes shakeWrong{0%,to{transform:translate(0)}20%{transform:translate(-6px)}40%{transform:translate(6px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}@keyframes slideInRight{0%{opacity:0;transform:translate(20px)}to{opacity:1;transform:translate(0)}}@keyframes slideInLeft{0%{opacity:0;transform:translate(-20px)}to{opacity:1;transform:translate(0)}}@keyframes pinPop{0%{transform:scale(.85)}to{transform:scale(1)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes popIn{0%{opacity:0;transform:scale(.92) translateY(8px)}to{opacity:1;transform:scale(1) translateY(0)}}@keyframes floatBadge{0%{transform:translateY(-4px);opacity:0}to{transform:translateY(0);opacity:1}}@keyframes spin{to{transform:rotate(360deg)}}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-size:16px;line-height:1.5}#app{max-width:430px;margin:0 auto;padding:24px 20px 40px}.screen-forward{animation:slideInRight .26s ease}.screen-back{animation:slideInLeft .26s ease}h1,h2,h3,.font-display{font-family:Poppins,sans-serif}.header-nav{display:flex;align-items:center;gap:8px;margin-bottom:18px}.header-title-row{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;margin-bottom:8px}.header-title-row h1{flex:1;min-width:0;font-size:20px;font-weight:800;margin:0;line-height:1.3}.header-reset-row{display:flex;justify-content:flex-end;margin-bottom:18px}.header-meta{color:var(--ink-soft);font-size:13px;margin:0 0 20px}.btn-icon{all:unset;box-sizing:border-box;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;background:var(--surface);border:1px solid var(--border);border-radius:100px;box-shadow:0 1px 4px #0000000d;flex-shrink:0}.btn-icon:active{background:var(--bg)}.btn-back{all:unset;box-sizing:border-box;cursor:pointer;display:inline-flex;align-items:center;gap:6px;max-width:62%;background:var(--surface);border:1px solid var(--border);color:var(--ink);font-weight:600;font-size:13.5px;padding:10px 16px;border-radius:100px;box-shadow:0 1px 4px #0000000d}.btn-back:active{background:var(--bg)}.btn-back .label{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.btn-reset{all:unset;box-sizing:border-box;cursor:pointer;display:inline-flex;align-items:center;gap:6px;background:var(--danger);color:#fff;font-family:Poppins,sans-serif;font-weight:700;font-size:13px;padding:11px 18px;border-radius:100px;flex-shrink:0;box-shadow:0 3px 10px #bc494547}.btn-reset:active{transform:scale(.97);box-shadow:0 1px 4px #bc49454d}.grid{display:grid;grid-template-columns:1fr;gap:12px;margin-top:16px}.card{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:16px;text-align:left;cursor:pointer;display:flex;align-items:center;gap:14px;transition:transform .15s ease,box-shadow .15s ease}.card:active{transform:scale(.98);background:var(--bg)}.card.static{cursor:default}.card.static:active{transform:none;background:var(--surface)}.card-icon{width:44px;height:44px;border-radius:14px;flex-shrink:0;display:flex;align-items:center;justify-content:center}.card-body{flex:1;min-width:0}.card h3{font-weight:700;font-size:16px;margin:0 0 3px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}.muted{color:var(--ink-soft);font-size:13px}.small{font-size:.8rem}.grade-badge{display:inline-block;background:var(--success-bg);color:var(--success);font-family:Poppins,sans-serif;font-weight:700;font-size:13px;padding:6px 10px;border-radius:100px;animation:floatBadge .3s ease}.tabs{display:flex;gap:20px;border-bottom:1px solid var(--border);margin-top:20px;margin-bottom:22px}.tab{background:none;border:none;padding:0 0 12px;font-weight:700;font-size:14px;color:var(--ink-faint);cursor:pointer;border-bottom:2px solid transparent}.tab.active{color:var(--ink);border-bottom-color:var(--accent)}.prose{font-size:15.5px;line-height:1.65}.prose h2{font-size:17px;font-weight:700;margin:20px 0 8px}.prose h3,.prose h4{font-weight:700;margin:16px 0 8px}.prose p{margin:0 0 12px}.prose ul{margin:0 0 12px;padding-left:20px}.prose li{margin-bottom:6px}.quiz-item{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:18px;box-shadow:0 2px 10px #0000000a;margin-bottom:14px}.badge{display:inline-block;font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;padding:4px 10px;border-radius:100px;margin-bottom:10px;background:var(--accent-soft);color:var(--accent-strong)}.badge.difficulty-1{background:var(--success-bg);color:var(--success)}.badge.difficulty-2{background:var(--warn-bg);color:var(--warn-ink)}.badge.difficulty-3{background:var(--danger-bg);color:var(--danger)}.question{font-family:Poppins,sans-serif;font-weight:700;font-size:16.5px;line-height:1.4;margin:0 0 16px}.options{display:flex;flex-direction:column;gap:10px;margin-bottom:14px}.option{all:unset;box-sizing:border-box;display:block;width:100%;text-align:left;background:var(--surface);color:var(--ink);border:2px solid var(--border);border-radius:14px;padding:13px 14px;cursor:pointer;font-weight:600;font-size:14.5px;line-height:1.4}button.option:active{background:var(--bg);transform:scale(.99)}.option.correct{border-color:var(--success);background:var(--success-bg);color:var(--success);animation:popCorrect .32s ease}.option.wrong{border-color:var(--danger);background:var(--danger-bg);color:var(--danger);animation:shakeWrong .32s ease}div.option{cursor:default}textarea{width:100%;border:2px solid var(--border);border-radius:14px;padding:12px 14px;font-family:inherit;font-size:14.5px;resize:vertical;min-height:90px}.btn{margin-top:10px;background:var(--accent);color:#fff;border:none;border-radius:14px;padding:14px;font-family:Poppins,sans-serif;font-weight:700;font-size:15px;cursor:pointer;width:100%}.btn.secondary{background:none;color:var(--ink);border:1px solid var(--border)}.btn.danger{background:var(--danger)}.feedback{background:var(--accent-soft);color:var(--accent-strong);border-radius:12px;padding:12px 14px;font-size:14px;line-height:1.5;margin-bottom:14px;animation:popIn .22s ease}.login{max-width:320px;margin:15vh auto 0;text-align:center;display:flex;flex-direction:column;align-items:center;gap:10px;animation:fadeIn .3s ease}.login-icon{width:64px;height:64px;border-radius:20px;background:var(--accent);display:flex;align-items:center;justify-content:center;margin-bottom:4px;box-shadow:0 8px 20px #8e57d84d}.login h1{font-size:26px;margin:0}.pin-boxes{display:flex;gap:8px;justify-content:center;position:relative;margin-top:8px}.pin-box{width:38px;height:48px;border-radius:12px;background:var(--surface);border:2px solid var(--border);display:flex;align-items:center;justify-content:center;font-family:Poppins,sans-serif;font-size:22px;font-weight:700;box-shadow:0 2px 6px #0000000a}.pin-box.filled{border-color:var(--accent);animation:pinPop .15s ease}.pin-hidden-input{position:absolute;top:0;right:0;bottom:0;left:0;opacity:0;border:none;font-size:16px;width:100%}.error{color:var(--danger);font-size:.9rem}.pending{display:flex;align-items:center;gap:8px;color:var(--ink-soft);font-size:13.5px;font-weight:600;margin-top:10px}.spinner{display:inline-block;width:14px;height:14px;border:2px solid var(--accent-soft);border-top-color:var(--accent);border-radius:50%;animation:spin .7s linear infinite}.voto-card{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:20px;box-shadow:0 2px 10px #0000000a}.voto-card-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px}.voto-card-header span{font-family:Poppins,sans-serif;font-weight:700;font-size:15.5px}.last-feedback{font-style:italic;color:var(--ink-soft);font-size:14px;line-height:1.55;margin:0;border-left:3px solid var(--accent-soft);padding-left:12px}.sound-toggle{position:fixed;top:16px;right:16px;width:38px;height:38px;border-radius:50%;background:var(--surface);border:1px solid var(--border);box-shadow:0 2px 8px #0000000f;display:flex;align-items:center;justify-content:center;cursor:pointer;z-index:80;padding:0}.modal-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;background:#140f2347;backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px);display:flex;align-items:center;justify-content:center;padding:20px;z-index:100;animation:fadeIn .18s ease}.modal{position:relative;background:var(--surface);border-radius:22px;padding:24px 22px 22px;max-width:360px;width:100%;box-shadow:0 20px 50px #0003;animation:popIn .22s ease}.modal h3{font-size:19px;font-weight:800;margin:0 0 10px}.modal p{margin:0 0 22px;color:var(--ink-soft);font-size:14.5px;line-height:1.5}.modal-close{position:absolute;top:14px;right:16px;background:none;border:none;font-size:18px;font-weight:700;line-height:1;cursor:pointer;color:var(--ink-soft);padding:6px}.modal-actions .btn{margin-top:0}