:root {
    --sidebar-width: 260px;
    --sidebar-bg: #0f172a;
    --sidebar-hover: #1e293b;
    --sidebar-active: #2563eb;
    --body-bg: #f1f5f9;
    --content-bg: #ffffff;
    --text-main: #0f172a;
}

body {
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    background: radial-gradient(circle at top left, #e2e8f0 0%, #f8fafc 45%, #eef2ff 100%);
    color: var(--text-main);
    min-height: 100vh;
}

.app-shell {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: var(--sidebar-width);
    background: linear-gradient(180deg, #0b1220 0%, var(--sidebar-bg) 100%);
    color: #e2e8f0;
    padding: 1.25rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    position: sticky;
    top: 0;
    height: 100vh;
}

.sidebar-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.04);
}

.brand-mark {
    width: 38px;
    height: 38px;
    border-radius: 10px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #3b82f6, #0ea5e9);
    color: #fff;
    font-size: 1.1rem;
}

.brand-title {
    font-weight: 700;
    color: #f8fafc;
    line-height: 1.2;
}

.brand-subtitle {
    font-size: 0.75rem;
    color: #94a3b8;
}

.menu {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.menu-link {
    border-radius: 10px;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: #cbd5e1;
    text-decoration: none;
    padding: 0.65rem 0.75rem;
    transition: all 0.2s ease;
    font-weight: 500;
}

.menu-link:hover {
    background: var(--sidebar-hover);
    color: #f8fafc;
}

.menu-link.active {
    background: linear-gradient(90deg, #1d4ed8, #2563eb);
    color: #fff;
}

.sidebar-footer {
    margin-top: auto;
    border-top: 1px solid rgba(148, 163, 184, 0.25);
    padding-top: 0.85rem;
}

.content {
    flex: 1;
    padding: 1.25rem;
}

.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.page-title {
    font-size: 1.35rem;
    font-weight: 700;
    margin: 0;
}

.stat-card {
    border: 0;
    border-radius: 16px;
    background: var(--content-bg);
    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.06);
}

.stat-label {
    font-size: 0.82rem;
    color: #64748b;
    margin-bottom: 0.35rem;
}

.stat-value {
    font-size: 1.6rem;
    font-weight: 700;
}

.card {
    border: 0;
    border-radius: 16px;
    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.05);
}

.table thead th {
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: #64748b;
}

.table td {
    vertical-align: middle;
}

.license-key {
    font-family: Consolas, "Courier New", monospace;
    font-size: 0.88rem;
    font-weight: 600;
}

.login-page {
    min-height: 100vh;
    background: radial-gradient(circle at top right, #dbeafe 0%, #eff6ff 45%, #e2e8f0 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.login-card {
    width: 100%;
    max-width: 420px;
    border: 0;
    border-radius: 18px;
    box-shadow: 0 16px 40px rgba(15, 23, 42, 0.12);
}

.table-responsive {
    border-radius: 12px;
}

@media (max-width: 992px) {
    .app-shell {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        position: static;
    }

    .content {
        padding: 1rem;
    }
}