:root{--brand: #004aad;--brand-dark: #00337f;--bg: #f7f8fa;--text: #333;--muted: #777;--danger: #dc3545;--focus-outline: 2px solid var(--brand)}*{box-sizing:border-box;margin:0;padding:0}body{font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Noto Sans,Helvetica,Arial,"Apple Color Emoji","Segoe UI Emoji";background:var(--bg);color:var(--text);line-height:1.6}.app{display:grid;grid-template-columns:240px 1fr;min-height:100vh}.sidebar{background:#0b1b33;color:#fff;padding:20px}.sidebar h2{font-size:18px;margin-bottom:16px;letter-spacing:.5px}.sidebar a{display:block;color:#fff;text-decoration:none;padding:10px 8px;border-radius:6px;margin-bottom:6px;transition:background .2s ease}.sidebar a:hover,.sidebar a:focus{background:#14325f;outline:none}.sidebar a.active{background:#14325f}.header{background:#024;color:#fff;padding:16px 24px;display:flex;align-items:center;justify-content:space-between}.main{padding:24px}.card{background:#fff;border-radius:12px;box-shadow:0 4px 12px #0000000f;padding:16px}h1{font-size:22px}h2{font-size:18px;margin-bottom:12px}button,.btn{background:var(--brand);color:#fff;border:none;border-radius:8px;padding:10px 14px;font-weight:600;cursor:pointer;transition:background .2s ease,transform .1s ease}button:hover,button:focus,.btn:hover,.btn:focus{background:var(--brand-dark);transform:translateY(-1px);outline:none;box-shadow:0 2px 4px #0000001a}button.secondary,.btn.secondary{background:#6c757d}button.danger,.btn.danger{background:var(--danger)}input,select,textarea{width:100%;padding:10px 12px;border:1px solid #ddd;border-radius:8px;margin:6px 0 12px;transition:border-color .2s ease,box-shadow .2s ease}input:focus,select:focus,textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px #004aad33}table{width:100%;border-collapse:collapse;margin-top:12px;background:#fff;border-radius:12px;overflow:hidden}th,td{text-align:left;padding:12px;border-bottom:1px solid #eee}th{background:var(--brand);color:#fff}tr:hover td{background:#f3f8ff}.alert{padding:12px;border-radius:8px;margin-bottom:12px}.alert.success{background:#d4edda;color:#155724}.alert.error{background:#f8d7da;color:#721c24}.footer{color:var(--muted);font-size:13px;padding:16px 24px}@media (max-width: 768px){.app{grid-template-columns:1fr}.sidebar{position:fixed;top:0;left:0;width:100%;padding:10px 20px;height:auto;z-index:1000;display:none}.header{margin-top:55px}}