:root {
    --primary: #2563eb;
    --bg: #f5f6fa;
    --text: #1f2430;
    --border: #d8dce3;
}
* { box-sizing: border-box; }
body { margin: 0; font-family: -apple-system, Segoe UI, Roboto, Arial, sans-serif; background: var(--bg); color: var(--text); }
.topbar { display: flex; align-items: center; gap: 24px; background: #fff; border-bottom: 1px solid var(--border); padding: 12px 24px; }
.brand { font-weight: 700; color: var(--primary); }
.mainnav { display: flex; gap: 16px; flex: 1; }
.mainnav a { color: var(--text); text-decoration: none; }
.mainnav a:hover { color: var(--primary); }
.usermenu a { margin-left: 8px; color: var(--primary); text-decoration: none; }
.content { max-width: 1100px; margin: 24px auto; padding: 0 24px; }
.cards { display: flex; gap: 16px; flex-wrap: wrap; margin-top: 16px; }
.card { display: block; padding: 20px; background: #fff; border: 1px solid var(--border); border-radius: 8px; text-decoration: none; color: var(--text); min-width: 160px; }
.card:hover { border-color: var(--primary); }
.datatable { width: 100%; border-collapse: collapse; background: #fff; }
.datatable th, .datatable td { padding: 10px; border-bottom: 1px solid var(--border); text-align: left; }
.auth-page { display: flex; align-items: center; justify-content: center; min-height: 100vh; }
.auth-box { background: #fff; padding: 32px; border-radius: 8px; border: 1px solid var(--border); width: 360px; }
.auth-box h1 { color: var(--primary); margin: 0 0 4px; }
form label { display: block; margin-top: 12px; margin-bottom: 4px; font-size: 14px; }
form input, form select { width: 100%; padding: 8px; border: 1px solid var(--border); border-radius: 4px; }
button { margin-top: 16px; padding: 10px 16px; background: var(--primary); color: #fff; border: none; border-radius: 4px; cursor: pointer; }
.error { color: #b91c1c; }
.success { color: #15803d; }