:root{--blue:#2857d8;--blue2:#163b9a;--mint:#a8cbbd;--ink:#17264b;--muted:#66728d;--bg:#f3f6fc;--line:#dce4f2;--good:#138a5b;--bad:#d44646;--white:#fff}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:"Noto Sans Thai","Tahoma",sans-serif;color:var(--ink);background:var(--bg);line-height:1.55}.hero{background:linear-gradient(135deg,#163b9a,#3478e5);color:#fff;padding:42px 20px 68px}.hero-inner{max-width:1080px;margin:auto}.hero h1{font-size:clamp(1.8rem,4vw,3rem);margin:10px 0 0}.hero p{margin:6px 0;opacity:.92}.badge{display:inline-block;background:#fff2;color:#fff;border:1px solid #fff5;border-radius:999px;padding:5px 14px;font-weight:700}.page{max-width:1080px;margin:-36px auto 40px;padding:0 18px}.card{background:#fff;border:1px solid var(--line);border-radius:20px;box-shadow:0 8px 26px #18377710;padding:26px;margin:0 0 20px}.card h2{margin:0 0 15px}.card h2 small{font-size:.75rem;color:var(--muted);white-space:nowrap}.grid3{display:grid;grid-template-columns:2fr .7fr 1fr;gap:14px}label{font-weight:700;display:block}input,select,textarea{width:100%;margin-top:6px;border:1.5px solid #ccd7e9;border-radius:10px;padding:11px 12px;font:inherit;color:var(--ink);background:#fff}textarea{resize:vertical}input:focus,select:focus,textarea:focus{outline:3px solid #2860db22;border-color:var(--blue)}.notice{background:#edf4ff;border-left:5px solid var(--blue);border-radius:10px;padding:13px 16px;margin-top:18px}.question{position:relative;padding-left:78px}.qno{position:absolute;left:24px;top:23px;width:38px;height:38px;border-radius:12px;display:grid;place-items:center;background:var(--blue);color:#fff;font-weight:800;font-size:1.2rem}.hint{color:var(--muted);margin-top:-8px}.battery-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:12px;margin:18px 0}.battery-item{background:#f7f9fd;border:1px solid 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12px}.circuit-body{display:grid;grid-template-columns:1.15fr 1fr;gap:18px;align-items:center}.diagram{position:relative;min-height:185px;background:#fbfcff;border-radius:12px;border:1px dashed #aebbd0;padding:12px}.wire{position:absolute;border:4px solid #1e2638}.wire.rect{left:12%;top:25%;width:76%;height:55%}.device-label{position:absolute;background:#fff;padding:2px 6px;font:bold 20px Arial;z-index:2}.n{position:absolute;z-index:3;background:#ef4056;color:#fff;width:25px;height:25px;border-radius:50%;display:grid;place-items:center;font-weight:800}.answers-grid{display:grid;gap:8px}.answers-grid label{display:grid;grid-template-columns:34px 1fr;align-items:center}.answers-grid select{margin:0}.correct{border-color:var(--good)!important;background:#effbf5!important}.wrong{border-color:var(--bad)!important;background:#fff2f2!important}.toolbar{position:sticky;bottom:0;z-index:10;background:#ffffffee;backdrop-filter:blur(8px);border:1px solid var(--line);box-shadow:0 -6px 24px 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#dfe8fb;border-top-color:var(--blue);border-radius:50%;display:flex;align-items:baseline;justify-content:center;padding-top:28px;margin:18px auto}.score-ring b{font-size:2.3rem}.admin-wrap{max-width:1250px;margin:30px auto;padding:0 18px}.admin-head{display:flex;align-items:center;justify-content:space-between;gap:15px}.filters{display:grid;grid-template-columns:1fr 220px auto;gap:10px;margin:15px 0}.table-wrap{overflow:auto;background:#fff;border-radius:15px;border:1px solid var(--line)}table{border-collapse:collapse;width:100%;min-width:980px}th,td{padding:11px 10px;border-bottom:1px solid var(--line);text-align:left;vertical-align:middle}th{background:#eaf0fc;position:sticky;top:0}td.actions{white-space:nowrap}button.small{border:0;border-radius:8px;padding:7px 10px;cursor:pointer}.detail-answer{white-space:pre-wrap;background:#f6f8fc;border-radius:8px;padding:8px}.login-card{max-width:450px;margin:12vh auto}.hidden{display:none!important}@media(max-width:760px){.grid3,.inline-q,.circuit-body{grid-template-columns:1fr}.battery-grid{grid-template-columns:repeat(2,1fr)}.symbol-grid{grid-template-columns:repeat(2,1fr)}.question{padding:72px 18px 20px}.component-list article{grid-template-columns:95px 1fr}.filters{grid-template-columns:1fr}.toolbar{position:static}.hero{padding-top:28px}}@media print{body{background:#fff}.hero{padding:20px;color:#000;background:#fff}.page{margin:0;max-width:none}.card{box-shadow:none;break-inside:avoid}.toolbar,.teacher-link,#scoreDialog,.toast{display:none!important}.question{padding-left:65px}}