:root {
    --bg: #0f1419;
    --surface: #1a2332;
    --surface2: #243044;
    --border: #2d3a4f;
    --text: #e7ecf3;
    --muted: #8b9cb3;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --success: #22c55e;
    --danger: #ef4444;
    --warning: #f59e0b;
    --radius: 12px;
    --shadow: 0 4px 24px rgba(0,0,0,.35);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: Tahoma, 'Segoe UI', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    min-height: 100vh;
}

.sidebar {
    background: var(--surface);
    border-left: 1px solid var(--border);
    padding: 1.5rem 1rem;
    position: sticky;
    top: 0;
    height: 100vh;
}

.brand {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 2rem;
    padding: 0 .5rem;
    color: var(--text);
}

.brand small {
    display: block;
    font-size: .75rem;
    color: var(--muted);
    font-weight: 400;
    margin-top: .25rem;
}

.nav a {
    display: flex;
    align-items: center;
    gap: .6rem;
    padding: .75rem 1rem;
    border-radius: 8px;
    color: var(--muted);
    margin-bottom: .25rem;
    transition: .15s;
}

.nav a:hover, .nav a.active {
    background: var(--surface2);
    color: var(--text);
    text-decoration: none;
}

.main {
    padding: 2rem;
    max-width: 1200px;
}

.page-header {
    margin-bottom: 1.5rem;
}

.page-header h1 {
    font-size: 1.5rem;
    margin-bottom: .25rem;
}

.page-header p {
    color: var(--muted);
    font-size: .9rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem;
}

.stat-card .label {
    color: var(--muted);
    font-size: .85rem;
    margin-bottom: .5rem;
}

.stat-card .value {
    font-size: 1.75rem;
    font-weight: 700;
}

.stat-card.primary .value { color: var(--primary); }
.stat-card.success .value { color: var(--success); }
.stat-card.warning .value { color: var(--warning); }

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.card h2 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    padding-bottom: .75rem;
    border-bottom: 1px solid var(--border);
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: .9rem;
}

th, td {
    padding: .75rem 1rem;
    text-align: right;
    border-bottom: 1px solid var(--border);
}

th {
    color: var(--muted);
    font-weight: 600;
    font-size: .8rem;
}

tr:hover td { background: rgba(255,255,255,.02); }

.badge {
    display: inline-block;
    padding: .2rem .6rem;
    border-radius: 999px;
    font-size: .75rem;
    font-weight: 600;
}

.badge-pending { background: rgba(245,158,11,.15); color: var(--warning); }
.badge-approved { background: rgba(34,197,94,.15); color: var(--success); }
.badge-rejected { background: rgba(239,68,68,.15); color: var(--danger); }

.btn {
    display: inline-flex;
    align-items: center;
    gap: .4rem;
    padding: .55rem 1rem;
    border: none;
    border-radius: 8px;
    font-family: inherit;
    font-size: .875rem;
    cursor: pointer;
    transition: .15s;
    text-decoration: none;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); text-decoration: none; color: #fff; }
.btn-success { background: var(--success); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-ghost { background: var(--surface2); color: var(--text); border: 1px solid var(--border); }
.btn-sm { padding: .35rem .75rem; font-size: .8rem; }

.btn-group { display: flex; gap: .5rem; flex-wrap: wrap; }

.form-group { margin-bottom: 1rem; }
.form-group label { display: block; margin-bottom: .4rem; color: var(--muted); font-size: .875rem; }
.form-control {
    width: 100%;
    padding: .65rem .85rem;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-family: inherit;
    font-size: .9rem;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
}

.alert {
    padding: .85rem 1rem;
    border-radius: 8px;
    margin-bottom: 1rem;
    font-size: .9rem;
}

.alert-error { background: rgba(239,68,68,.12); color: #fca5a5; border: 1px solid rgba(239,68,68,.3); }
.alert-success { background: rgba(34,197,94,.12); color: #86efac; border: 1px solid rgba(34,197,94,.3); }

.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.login-box {
    width: 100%;
    max-width: 400px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
}

.login-box h1 {
    text-align: center;
    margin-bottom: .5rem;
    font-size: 1.25rem;
}

.login-box .subtitle {
    text-align: center;
    color: var(--muted);
    font-size: .875rem;
    margin-bottom: 1.5rem;
}

.detail-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.detail-item label {
    display: block;
    color: var(--muted);
    font-size: .8rem;
    margin-bottom: .2rem;
}

.detail-item span { font-weight: 500; }

.receipt-img {
    max-width: 100%;
    max-height: 400px;
    border-radius: 8px;
    border: 1px solid var(--border);
    margin-top: 1rem;
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--muted);
}

@media (max-width: 768px) {
    .layout { grid-template-columns: 1fr; }
    .sidebar {
        position: static;
        height: auto;
        border-left: none;
        border-bottom: 1px solid var(--border);
    }
    .nav { display: flex; flex-wrap: wrap; gap: .25rem; }
    .nav a { padding: .5rem .75rem; font-size: .85rem; }
    .main { padding: 1rem; }
    table { font-size: .8rem; }
    th, td { padding: .5rem; }
}