:root{--bg:#faf8f4;--ink:#263b35;--green:#176b58;--muted:#738079;--line:#e3e7de;--soft:#e8efe5;--orange:#c9653e}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;font-size:15px;line-height:1.6}button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:default}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #d6a455;outline-offset:4px}[hidden]{display:none!important}.app{max-width:960px;margin:auto;padding:0 36px 110px}.topbar{display:flex;justify-content:space-between;align-items:center;padding:30px 0;border-bottom:1px solid var(--line);margin-bottom:45px}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink);font-weight:750;font-size:21px;letter-spacing:-.6px}.brand small{display:block;font-size:9px;letter-spacing:2px;font-weight:600;color:var(--muted)}.brand-icon{background:var(--green);color:white;border-radius:14px;width:48px;height:48px;display:flex;align-items:center;justify-content:center;position:relative;font-size:23px}.brand-icon span{font-size:10px;position:absolute;right:5px;top:3px}.tag,.eyebrow{font-size:10px;letter-spacing:2px;font-weight:750;color:var(--green)}h1{font-size:clamp(38px,5.8vw,58px);line-height:1.14;letter-spacing:-2.3px;margin:14px 0 20px;font-weight:750}h1 span{color:var(--green)}h2{font-size:22px;letter-spacing:-.6px;line-height:1.3;margin:0 0 12px}.lead{color:var(--muted);line-height:1.8;margin-bottom:30px}.hero-card{border:1px solid #d8e4d5;background:#edf2e8;border-radius:26px;padding:35px 34px;display:flex;align-items:center;gap:42px;overflow:hidden;margin:30px 0 38px}.hero-copy{flex:1}.hero-copy h2{font-size:27px;margin-top:17px}.hero-copy 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#b6c9af;border-radius:50%;width:230px;height:110px;transform:rotate(-35deg)}.o2{transform:rotate(35deg)}.o3{transform:rotate(90deg)}.element-art{width:105px;height:120px;border-radius:16px;background:var(--green);color:#fff;box-shadow:0 12px 25px #176b581c;display:flex;flex-direction:column;align-items:center;justify-content:center;z-index:1;transform:rotate(-8deg)}.element-art small{position:absolute;left:12px;top:7px;font-size:12px;color:#b5d4c6}.element-art strong{font-size:61px;line-height:1.1}.element-art span{font-size:12px;letter-spacing:1px}.electron{position:absolute;width:13px;height:13px;background:#d0a45b;border:3px solid #edf2e8;border-radius:50%;left:14px;top:75px}.e2{left:auto;right:26px;top:162px;background:var(--green)}.section-title{display:flex;justify-content:space-between;align-items:center;gap:12px}.section-title h2{font-size:18px;margin:0}.metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin:17px 0 28px}.metric{border:1px solid 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button{flex:1;background:none;border:0;border-radius:12px;font-size:11px;color:var(--muted);padding:7px}.bottom-nav button span{display:block;font-size:21px;line-height:1.3}.bottom-nav button.active{background:var(--soft);color:var(--green);font-weight:700}.panel{background:#fffdfa;border:1px solid var(--line);border-radius:23px;padding:26px}.field-label{display:block;font-size:12px;font-weight:650;margin-bottom:8px}input[type=search],#symbol-input{width:100%;border:1px solid #d7dfd5;border-radius:12px;padding:14px;background:#fafbf7;color:var(--ink)}.preset-row{display:flex;flex-wrap:wrap;gap:8px;margin:16px 0 25px}.preset-row button{border:1px solid var(--line);background:white;border-radius:25px;padding:8px 12px;font-size:11px;color:var(--green);font-weight:600}.preset-row button:hover{background:var(--soft)}.selection-head{display:flex;justify-content:space-between;font-size:11px;color:var(--muted);padding-bottom:12px}.selection-head 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30px;background:#e1e7dc}progress::-webkit-progress-bar{background:#e1e7dc;border-radius:10px}progress::-webkit-progress-value{background:var(--green);border-radius:10px}progress::-moz-progress-bar{background:var(--green)}.question-card{max-width:580px;margin:auto;text-align:center;padding:30px;background:#fffdfa;border-radius:25px;border:1px solid var(--line)}.symbol-prompt{font-size:96px;margin:16px 0 0;color:var(--green)}.name-prompt{font-size:48px;margin:32px 0 22px;overflow-wrap:anywhere}.options{display:grid;gap:10px;margin-top:26px}.option{display:flex;align-items:center;gap:15px;text-align:left;border:1px solid var(--line);border-radius:12px;background:white;padding:14px 18px;color:var(--ink);font-weight:600;min-height:54px}.option span{font-size:11px;font-weight:500;color:var(--muted)}.option:hover:enabled{border-color:var(--green);background:#f1f6ed}.option.correct{background:#e4f1df;border-color:#66a674}.option.wrong{background:#fbe9e3;border-color:#cf7757}.feedback{padding:16px 10px;margin:15px 0;border-radius:12px;font-weight:600;font-size:14px}.good{background:#edf5e8;color:var(--green)}.bad{background:#fbede5;color:#9e492b}#symbol-form{margin-top:25px;text-align:left}#symbol-input{font-size:32px;text-align:center;font-weight:700;letter-spacing:4px;margin-bottom:15px}.result-panel{max-width:650px;margin:auto;text-align:center}.result-score strong{font-size:72px;letter-spacing:-4px;color:var(--green);display:block;line-height:1.3}.result-score span{font-size:13px;color:var(--muted)}.answer-row,.history-row{display:flex;align-items:center;justify-content:space-between;gap:15px;border-bottom:1px solid var(--line);padding:13px 0;font-size:13px;text-align:left}.answer-row 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.height-0{height:3%}.height-1{height:10%}.height-2{height:20%}.height-3{height:30%}.height-4{height:40%}.height-5{height:50%}.height-6{height:60%}.height-7{height:70%}.height-8{height:80%}.height-9{height:90%}.height-10{height:100%}