:root {
    --primary-color: #1a2e4a;
    --secondary-color: #0d4b6e;
    --accent-color: #fbbf24;
}

.gradient-bg {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.card-hover {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card-hover:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.sidebar-item {
    transition: background-color 0.3s ease;
}

.sidebar-item:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.active-sidebar-item {
    background-color: rgba(255, 255, 255, 0.2);
    border-left: 4px solid white;
}

.fuel-icon {
    color: var(--accent-color);
}

/* Melhorias de acessibilidade */
[aria-current="page"] {
    font-weight: bold;
}

/* Focus styles para acessibilidade */
button:focus, a:focus, select:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Otimizações para mobile */
@media (max-width: 768px) {
    .mobile-collapse {
        display: none;
    }
    
    .mobile-expand {
        display: block;
    }
}