/* Responsive design - Mobile-first approach */

/* Mobile: < 640px */
@media (max-width: 639px) {
    h1 {
        font-size: 32px;
    }
    
    h2 {
        font-size: 28px;
    }
    
    h3 {
        font-size: 24px;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .modal {
        padding: var(--spacing-md);
        max-height: 95vh;
    }
    
    .btn {
        width: 100%;
    }
    
    .header-content {
        padding: 0 var(--spacing-sm);
    }
    
    .main-content {
        padding: var(--spacing-md) 0;
    }
    
    .grid.grid-2 {
        grid-template-columns: 1fr;
    }
}

/* Tablet: 640px - 1024px */
@media (min-width: 640px) and (max-width: 1023px) {
    .grid-3,
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-2 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Desktop: > 1024px */
@media (min-width: 1024px) {
    .grid-3 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .grid-4 {
        grid-template-columns: repeat(4, 1fr);
    }
}