:root{--bg:#f5f7fb;--card:#fff;--line:#e6e9ef;--text:#172033;--muted:#6c7485;--primary:#172a52;--accent:#f1b624;--good:#1f8f5f;--bad:#c84b4b}*{box-sizing:border-box}body{margin:0;font-family:'Malgun Gothic','Apple SD Gothic Neo',Arial,sans-serif;background:var(--bg);color:var(--text)}a{text-decoration:none;color:inherit}.topbar{height:68px;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 28px;position:sticky;top:0;z-index:20}.brand{font-weight:800;font-size:19px;letter-spacing:-.5px}.brand span{color:var(--accent)}.container{max-width:1180px;margin:0 auto;padding:32px 22px}.hero{max-width:720px;margin:55px auto}.card{background:var(--card);border:1px solid var(--line);border-radius:16px;box-shadow:0 6px 22px rgba(20,32,55,.05)}.intro{padding:36px}.kicker{font-size:13px;color:var(--primary);font-weight:800}.title{font-size:30px;line-height:1.28;margin:8px 0 10px;letter-spacing:-1.2px}.desc{color:var(--muted);line-height:1.65}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:28px}.field{display:flex;flex-direction:column;gap:8px}.field.full{grid-column:1/-1}label{font-weight:700;font-size:14px}input,select,textarea{width:100%;border:1px solid #d9deea;border-radius:10px;background:#fff;padding:13px 14px;font:inherit;color:var(--text);outline:none}input:focus,select:focus,textarea:focus{border-color:#8290ad;box-shadow:0 0 0 3px rgba(23,42,82,.07)}button{border:0;border-radius:10px;padding:12px 18px;font:inherit;font-weight:800;cursor:pointer}.btn-primary{background:var(--primary);color:#fff}.btn-secondary{background:#eef1f7;color:var(--primary)}.btn-accent{background:var(--accent);color:#202020}.notice{margin-top:20px;padding:14px;background:#f8fafc;border-radius:10px;color:#596273;font-size:13px;line-height:1.6}.exam-shell{display:grid;grid-template-columns:280px 1fr;gap:20px}.sidebar{padding:18px;height:calc(100vh - 112px);position:sticky;top:88px}.student{padding-bottom:16px;border-bottom:1px solid var(--line)}.student strong{display:block}.student small{color:var(--muted)}.progress{margin:18px 0}.progress-head{display:flex;justify-content:space-between;font-size:13px;font-weight:700}.bar{height:8px;background:#eef1f5;border-radius:20px;margin-top:8px;overflow:hidden}.bar i{display:block;height:100%;background:var(--primary);width:0}.qnav{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.qnav button{padding:10px 0;background:#f2f4f8;color:#586174}.qnav button.active{background:var(--primary);color:#fff}.qnav button.done{outline:2px solid #b8c4dd}.exam-main{padding:28px;min-height:700px}.question-meta{display:flex;gap:8px;align-items:center;color:var(--muted);font-size:13px}.pill{background:#eef1f7;border-radius:999px;padding:5px 10px;color:#44506a;font-weight:700}.question-title{font-size:24px;margin:14px 0 8px}.prompt{font-size:16px;line-height:1.8;white-space:pre-wrap}.choices{display:grid;gap:10px;margin:24px 0}.choice{display:flex;gap:12px;align-items:center;border:1px solid var(--line);border-radius:12px;padding:14px;cursor:pointer}.choice:hover{border-color:#a9b4ca}.choice input{width:auto}.answer-short{margin:24px 0;max-width:480px}.editor{margin-top:20px}.editor textarea{min-height:320px;background:#101625;color:#eef2ff;font-family:Consolas,monospace;font-size:14px;line-height:1.55;border-radius:12px}.run-result{margin-top:10px;padding:12px;border-radius:10px;background:#f1f4f8;font-size:13px;white-space:pre-wrap}.exam-actions{display:flex;justify-content:space-between;gap:10px;margin-top:28px;padding-top:20px;border-top:1px solid var(--line)}.timer{font-weight:900;font-size:17px}.admin-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-bottom:18px}.metric{padding:20px}.metric small{color:var(--muted)}.metric strong{display:block;font-size:28px;margin-top:8px}.panel{padding:22px;margin-top:18px}.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse;font-size:14px}th,td{text-align:left;padding:12px 10px;border-bottom:1px solid var(--line)}th{color:#667085;font-size:12px}.bands{font-weight:800}.analytics{display:grid;gap:12px}.analytic-row{display:grid;grid-template-columns:150px 1fr 56px;align-items:center;gap:12px}.analytic-row .bar{margin:0}.modal{position:fixed;inset:0;background:rgba(12,18,30,.45);display:none;align-items:center;justify-content:center;padding:20px;z-index:50}.modal.open{display:flex}.modal-card{background:white;border-radius:16px;max-width:800px;width:100%;max-height:85vh;overflow:auto;padding:24px}.muted{color:var(--muted)}.right{display:flex;align-items:center;gap:12px}@media(max-width:850px){.exam-shell{grid-template-columns:1fr}.sidebar{height:auto;position:static}.form-grid,.admin-grid{grid-template-columns:1fr}.field.full{grid-column:auto}.analytic-row{grid-template-columns:110px 1fr 48px}.topbar{padding:0 16px}}