:root{--navy:#001953;--navy2:#16337a;--navy-light:#e2e7f1;--navy-mid:#b9c4dc;--gold:#fb6b5b;--gold2:#fc8d80;--gold-light:#fee9e6;--gold-bg:#fee9e6;--gold-border:#fac6bf;--bg:#fff;--bg2:#f4f3ed;--bg3:#eceef4;--bg4:#e2e7f1;--border:#0019531a;--border2:#0019532e;--text:#001953;--text2:#46516b;--text3:#8590ab;--green:#1a7a4a;--green-bg:#1a7a4a12;--green-border:#1a7a4a33;--red:#c0392b;--red-bg:#c0392b12;--radius:6px;--radius-lg:12px;--font-display:"Tinos", Georgia, serif;--font-body:"Inter", sans-serif;--font-mono:"IBM Plex Mono", monospace}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:var(--font-body);-webkit-font-smoothing:antialiased;min-height:100vh;font-size:18px;line-height:1.68}a{color:inherit;text-decoration:none}.layout{grid-template-columns:250px 1fr;min-height:100vh;display:grid}.sidebar{background:var(--navy);flex-direction:column;height:100vh;padding:28px 0;display:flex;position:sticky;top:0;overflow-y:auto}.sidebar-logo{border-bottom:1px solid #ffffff1a;margin-bottom:20px;padding:0 22px 22px}.sidebar-logo img{opacity:.95;width:auto;height:32px}.sidebar-logo-sub{color:#ffffff59;font-size:11px;font-family:var(--font-mono);letter-spacing:.08em;text-transform:uppercase;margin-top:6px}.sidebar-nav{flex-direction:column;flex:1;gap:2px;padding:0 12px;display:flex}.nav-item{border-radius:var(--radius);color:#fff9;cursor:pointer;border:1px solid #0000;align-items:center;gap:10px;padding:11px 14px;font-size:16px;text-decoration:none;transition:all .15s;display:flex}.nav-item:hover{color:#ffffffe6;background:#ffffff14}.nav-item.active{color:#fff;background:#ffffff1f;border-color:#ffffff26}.nav-icon{text-align:center;flex-shrink:0;width:20px;font-size:16px}.main{background:var(--bg);overflow-y:auto}.page-header{border-bottom:1px solid var(--border);background:var(--bg);padding:40px 52px 28px}.page-title{font-family:var(--font-display);color:var(--navy);letter-spacing:-.02em;margin-bottom:7px;font-size:36px;font-weight:500}.page-sub{color:var(--text3);font-size:17px;font-weight:300;line-height:1.5}.page-content{padding:36px 52px}.card{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-lg);padding:24px 28px}.card+.card{margin-top:14px}.card-title{color:var(--text);margin-bottom:8px;font-size:19px;font-weight:500}.card-body{color:var(--text2);font-size:17px;line-height:1.7}.exam-paper{background-image:repeating-linear-gradient(-45deg,#0000,#0000 28px,#00195305 28px 29px)}.badge{font-size:13px;font-family:var(--font-mono);letter-spacing:.02em;border-radius:4px;padding:4px 10px;display:inline-block}.badge-gold{background:var(--gold-light);color:var(--gold);border:1px solid var(--gold-border)}.badge-green{background:var(--green-bg);color:var(--green);border:1px solid 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14px}.metrics{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:14px;margin-bottom:32px;display:grid}.metric{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius-lg);padding:20px 24px}.metric-label{color:var(--text3);font-size:12px;font-family:var(--font-mono);text-transform:uppercase;letter-spacing:.07em;margin-bottom:10px}.metric-value{font-family:var(--font-mono);color:var(--navy);font-size:30px;font-weight:500}textarea{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);width:100%;font-family:var(--font-body);color:var(--text);resize:vertical;min-height:130px;padding:16px 18px;font-size:17px;line-height:1.65;transition:border-color .15s}textarea:focus{border-color:var(--border2);outline:none}textarea::placeholder{color:var(--text3)}.model-answer{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);margin-top:16px;padding:18px 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