:root {
    --primary-gradient: linear-gradient(135deg, #0d6efd 0%, #6610f2 100%);
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: #f4f6f9;
}

main.container {
    flex: 1;
}

.auth-card {
    max-width: 420px;
    margin: 2rem auto;
}

.card-dashboard {
    border: none;
    box-shadow: 0 0.25rem 1rem rgba(0, 0, 0, 0.06);
    border-radius: 0.75rem;
}

.vless-key-box {
    font-family: ui-monospace, monospace;
    font-size: 0.85rem;
    word-break: break-all;
    background: #f8f9fa;
    border-radius: 0.5rem;
    padding: 1rem;
}

.admin-body {
    background: #eef1f5;
}

.admin-sidebar {
    background: #fff;
    min-height: calc(100vh - 56px);
    border-right: 1px solid #dee2e6;
}

.admin-sidebar .nav-link {
    color: #495057;
    border-radius: 0.375rem;
    margin-bottom: 0.25rem;
}

.admin-sidebar .nav-link:hover,
.admin-sidebar .nav-link.active {
    background: #e7f1ff;
    color: #0d6efd;
}

.stat-card {
    border: none;
    border-radius: 0.75rem;
    transition: transform 0.15s;
}

.stat-card:hover {
    transform: translateY(-2px);
}

.stat-card .display-6 {
    font-weight: 700;
}

.badge-expiry-lg {
    font-size: 0.9rem;
    padding: 0.5em 0.75em;
}

.tariff-card {
    cursor: pointer;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.tariff-card:has(input:checked) {
    border-color: #0d6efd;
    box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.25);
}

.instruction-content h2,
.instruction-content h3 {
    margin-top: 1.5rem;
}

.instruction-content pre {
    background: #212529;
    color: #f8f9fa;
    padding: 1rem;
    border-radius: 0.5rem;
}