:root {
    --navy: #001f3f;
    --deep: #003b66;
    --sapphire: #005f99;
    --ocean: #0096c7;
    --aqua: #00d4ff;
    --ink: #082235;
    --muted: #587184;
    --border: #dce6ed;
    --bg: #f4f7fa;
    --white: #ffffff;
    --red: #e74c3c;
    --green: #27ae60;
    --amber: #f39c12;
    --radius: 12px;
    --shadow: 0 2px 12px rgba(0,31,63,.08);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: Inter, -apple-system, Arial, sans-serif;
    background: var(--bg);
    color: var(--ink);
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 250px;
    background: var(--navy);
    color: var(--white);
    padding: 24px 0;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 10;
}

.sidebar-brand {
    padding: 0 20px 24px;
    border-bottom: 1px solid rgba(255,255,255,.1);
    margin-bottom: 16px;
    font-size: 18px;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
}

.sidebar-nav { list-style: none; }
.sidebar-nav li a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 20px;
    color: rgba(255,255,255,.7);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: .2s;
}
.sidebar-nav li a:hover,
.sidebar-nav li a.active {
    background: rgba(255,255,255,.1);
    color: var(--white);
}

.main {
    margin-left: 250px;
    flex: 1;
    padding: 24px 32px;
    min-height: 100vh;
}

.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 28px;
    padding-bottom: 18px;
    border-bottom: 1px solid var(--border);
}

.topbar h1 { font-size: 22px; font-weight: 700; color: var(--navy); }
.topbar-right { display: flex; align-items: center; gap: 16px; }
.topbar-right .username { font-size: 14px; color: var(--muted); }

.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 18px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    border: 1px solid transparent;
    cursor: pointer;
    text-decoration: none;
    transition: .2s;
}
.btn-primary { background: linear-gradient(135deg, var(--deep), var(--ocean)); color: var(--white); }
.btn-primary:hover { opacity: .9; }
.btn-secondary { background: var(--white); color: var(--navy); border-color: var(--border); }
.btn-secondary:hover { background: var(--bg); }
.btn-danger { background: var(--red); color: var(--white); }
.btn-danger:hover { opacity: .9; }
.btn-sm { padding: 6px 12px; font-size: 13px; }
.btn-amber { background: var(--amber); color: var(--white); }
.btn-green { background: var(--green); color: var(--white); }

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}
th, td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    font-size: 14px;
}
th {
    background: var(--bg);
    font-weight: 700;
    color: var(--navy);
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: .04em;
}
tr:last-child td { border-bottom: none; }
tr:hover td { background: #f8fafc; }

.card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 24px;
}

.card h2 { font-size: 18px; margin-bottom: 16px; color: var(--navy); }

.form-group { margin-bottom: 18px; }
.form-group label {
    display: block;
    font-weight: 600;
    font-size: 14px;
    color: var(--navy);
    margin-bottom: 6px;
}
.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    font-family: inherit;
    color: var(--ink);
    background: var(--white);
}
.form-group textarea { min-height: 120px; resize: vertical; }
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--ocean);
    box-shadow: 0 0 0 3px rgba(0,150,199,.15);
}

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }

.alert {
    padding: 14px 18px;
    border-radius: 8px;
    margin-bottom: 18px;
    font-size: 14px;
}
.alert-success { background: #d4edda; color: #155724; border: 1px solid #c3e6cb; }
.alert-error { background: #f8d7da; color: #721c24; border: 1px solid #f5c6cb; }

.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--navy), var(--deep));
}

.login-card {
    background: var(--white);
    border-radius: 16px;
    padding: 40px;
    width: min(420px, calc(100% - 40px));
    box-shadow: 0 20px 60px rgba(0,0,0,.3);
}

.login-card h1 {
    font-size: 24px;
    color: var(--navy);
    margin-bottom: 6px;
    text-align: center;
}
.login-card p {
    color: var(--muted);
    text-align: center;
    margin-bottom: 24px;
    font-size: 14px;
}

.login-card .form-group { margin-bottom: 16px; }
.login-card .btn { width: 100%; justify-content: center; padding: 12px; }

.badge {
    display: inline-flex;
    padding: 3px 10px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 700;
}
.badge-success { background: #d4edda; color: #155724; }
.badge-danger { background: #f8d7da; color: #721c24; }
.badge-warning { background: #fff3cd; color: #856404; }

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 18px;
    margin-bottom: 28px;
}
.stat-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--shadow);
}
.stat-card .stat-number {
    font-size: 32px;
    font-weight: 800;
    color: var(--navy);
}
.stat-card .stat-label {
    font-size: 13px;
    color: var(--muted);
    margin-top: 4px;
}

.actions-cell { display: flex; gap: 6px; flex-wrap: nowrap; }

.empty-state {
    text-align: center;
    padding: 40px;
    color: var(--muted);
}

@media (max-width: 768px) {
    .sidebar { width: 60px; }
    .sidebar-brand span, .sidebar-nav li a span { display: none; }
    .main { margin-left: 60px; padding: 16px; }
    .form-row { grid-template-columns: 1fr; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
}