:root {
    --color-primary: #1877f2;
    --color-primary-dark: #145dbf;
    --color-bg: #f0f2f5;
    --color-surface: #ffffff;
    --color-border: #e4e6eb;
    --color-text: #1c1e21;
    --color-text-muted: #606770;
    --color-danger: #dc2626;
    --color-danger-bg: #fee2e2;
    --color-success: #137333;
    --color-success-bg: #e6f4ea;
    --color-warning: #ea580c;
    --color-warning-bg: #fff7ed;
    --radius-card: 14px;
    --radius-control: 8px;
    --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.04);
    --shadow-md: 0 4px 16px rgba(16, 24, 40, 0.06);
    --shadow-lg: 0 12px 28px rgba(16, 24, 40, 0.10);
}

* {
    box-sizing: border-box;
}

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
}

main.container {
    max-width: 1140px;
}

/* Topbar */
.topbar {
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.topbar .brand {
    font-size: 1.05rem;
    font-weight: 800;
    color: var(--color-text);
    letter-spacing: -0.2px;
    text-decoration: none;
    white-space: normal;
    line-height: 1.25;
}

    .topbar .brand span {
        color: var(--color-primary);
        white-space: nowrap;
    }

@media (min-width: 768px) {
    .topbar .brand {
        font-size: 1.2rem;
    }
}

.topbar .nav-link {
    color: var(--color-text-muted);
    font-weight: 600;
    font-size: 0.92rem;
    border-radius: var(--radius-control);
    padding: 0.5rem 0.85rem;
    transition: background-color 0.15s ease, color 0.15s ease;
}

    .topbar .nav-link:hover {
        color: var(--color-text);
        background-color: var(--color-bg);
    }

    .topbar .nav-link.active {
        color: var(--color-primary);
        background-color: #e7f3ff;
        font-weight: 700;
    }

.btn-logout {
    background: var(--color-danger-bg);
    color: var(--color-danger);
    font-weight: 600;
    border: none;
    border-radius: var(--radius-control);
    padding: 0.45rem 0.9rem;
    font-size: 0.9rem;
    transition: background 0.2s, color 0.2s;
}

    .btn-logout:hover {
        background: var(--color-danger);
        color: white;
    }

/* Cards */
.card {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-card);
    box-shadow: var(--shadow-sm);
}

/* Stat tiles (dashboard) */
.stat-tile {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-card);
    padding: 20px;
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

    .stat-tile:hover {
        box-shadow: var(--shadow-md);
        transform: translateY(-2px);
    }

.stat-icon {
    width: 48px;
    height: 48px;
    min-width: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
}

.stat-icon.bg-blue { background: #e7f3ff; color: var(--color-primary); }
.stat-icon.bg-green { background: var(--color-success-bg); color: var(--color-success); }
.stat-icon.bg-purple { background: #f3e8ff; color: #9333ea; }
.stat-icon.bg-orange { background: var(--color-warning-bg); color: var(--color-warning); }

.stat-value {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--color-text);
    line-height: 1.1;
}

.stat-label {
    font-size: 0.82rem;
    color: var(--color-text-muted);
    font-weight: 500;
}

/* Buttons */
.btn {
    border-radius: var(--radius-control);
    font-weight: 600;
    padding: 0.5rem 1rem;
    transition: background-color 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease, transform 0.1s ease;
}

    .btn:active {
        transform: scale(0.98);
    }

.btn-primary {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    box-shadow: 0 1px 2px rgba(24, 119, 242, 0.25);
}

    .btn-primary:hover, .btn-primary:focus {
        background-color: var(--color-primary-dark);
        border-color: var(--color-primary-dark);
    }

.btn-outline-primary {
    color: var(--color-primary);
    border-color: var(--color-primary);
}

    .btn-outline-primary:hover {
        background-color: var(--color-primary);
        border-color: var(--color-primary);
    }

.btn-outline-secondary {
    color: var(--color-text-muted);
    border-color: var(--color-border);
}

    .btn-outline-secondary:hover {
        background-color: var(--color-bg);
        color: var(--color-text);
        border-color: var(--color-border);
    }

/* Forms */
.form-control, .form-select {
    border-radius: var(--radius-control);
    border-color: var(--color-border);
    padding: 0.55rem 0.8rem;
}

    .form-control:focus, .form-select:focus {
        border-color: var(--color-primary);
        box-shadow: 0 0 0 0.2rem rgba(24, 119, 242, 0.15);
    }

/* Tables */
.table {
    background: var(--color-surface);
    border-radius: var(--radius-card);
    overflow: hidden;
    margin-bottom: 0;
}

    .table thead th {
        text-transform: uppercase;
        font-size: 0.72rem;
        letter-spacing: 0.04em;
        color: var(--color-text-muted);
        border-bottom: 1px solid var(--color-border);
        font-weight: 700;
        padding-top: 0.9rem;
        padding-bottom: 0.9rem;
    }

    .table tbody td {
        vertical-align: middle;
        padding-top: 0.75rem;
        padding-bottom: 0.75rem;
    }

    .table tbody tr:hover {
        background-color: var(--color-bg);
    }

/* Alerts */
.alert {
    border-radius: var(--radius-control);
}

.alert-success {
    background-color: var(--color-success-bg);
    color: var(--color-success);
    border: none;
}

.alert-danger {
    background-color: var(--color-danger-bg);
    color: var(--color-danger);
    border: none;
}

.alert-warning {
    background-color: var(--color-warning-bg);
    color: var(--color-warning);
    border: none;
}

/* Status pills */
.pill {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    padding: 3px 10px;
    border-radius: 999px;
}

.pill-yes {
    background: var(--color-success-bg);
    color: var(--color-success);
}

.pill-no {
    background: var(--color-bg);
    color: var(--color-text-muted);
}

/* Generic content panel (forms, tables) */
.panel {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-card);
    padding: 32px;
    box-shadow: var(--shadow-sm);
}

.panel .table {
    box-shadow: none;
    border: 1px solid var(--color-border);
}

.page-header {
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--color-text);
    letter-spacing: -0.3px;
    margin-bottom: 1.5rem;
}

.form-label {
    font-weight: 600;
    font-size: 0.82rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.02em;
}

.form-actions {
    border-top: 1px solid var(--color-border);
    margin-top: 1.75rem;
    padding-top: 1.25rem;
}

.form-section + .form-section {
    margin-top: 2rem;
    padding-top: 1.75rem;
    border-top: 1px solid var(--color-border);
}

.form-section-title {
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--color-primary);
    margin-bottom: 1rem;
}

/* Empty states */
.empty-state {
    text-align: center;
    padding: 48px 20px;
    color: var(--color-text-muted);
    background: var(--color-bg);
    border-radius: var(--radius-control);
    border: 1px dashed var(--color-border);
}

/* Auth pages */
.auth-page {
    min-height: calc(100vh - 90px);
    display: flex;
    align-items: center;
}

.auth-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-card);
    padding: 36px;
    box-shadow: var(--shadow-lg);
}