:root {
    --sidebar-width: 260px;
    --primary: #0d6efd;
    --bg-light: #f4f6f9;
}
body { margin: 0; font-family: 'Segoe UI', system-ui, sans-serif; background: var(--bg-light); }

.sidebar {
    width: var(--sidebar-width); min-height: 100vh; position: fixed; left: 0; top: 0;
    z-index: 1000; transition: transform 0.3s ease; background: #fff;
}
.main-content {
    margin-left: var(--sidebar-width); padding: 2rem; min-height: 100vh; transition: margin 0.3s;
}
.nav-link { color: #495057; border-radius: 8px; padding: 0.75rem 1rem; font-weight: 500; margin-bottom: 0.25rem; }
.nav-link:hover { background: #e9ecef; color: var(--primary); }
.nav-link.active { background: var(--primary); color: #fff; }
.nav-link i { width: 20px; text-align: center; margin-right: 0.5rem; }

.mobile-toggle { display: none; position: fixed; top: 1rem; right: 1rem; z-index: 1001; box-shadow: 0 2px 8px rgba(0,0,0,0.15); }

@media (max-width: 992px) {
    .sidebar { transform: translateX(-100%); }
    .sidebar.show { transform: translateX(0); }
    .main-content { margin-left: 0; padding: 1.5rem; }
    .mobile-toggle { display: block; }
}