:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background-color: #f8f9fa;
}

main {
    flex: 1;
}

.navbar-brand {
    font-weight: 600;
    font-size: 1.25rem;
}

.converter-card {
    border: 2px solid transparent;
    border-radius: 12px;
    transition: all 0.3s ease;
    cursor: pointer;
    background: white;
}

.converter-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.icon-wrapper {
    font-size: 2rem;
    padding: 1rem 0;
}

.icon-wrapper i {
    vertical-align: middle;
}

.upload-area {
    border: 2px dashed #dee2e6;
    border-radius: 12px;
    background-color: #f8f9fa;
    cursor: pointer;
    transition: all 0.3s ease;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary-color);
    background-color: rgba(13, 110, 253, 0.05);
}

.upload-area.dragover {
    transform: scale(1.02);
}

.btn-convert {
    border-radius: 20px;
    padding: 0.5rem 1.5rem;
}

.progress {
    height: 8px;
    border-radius: 4px;
}

.modal-content {
    border-radius: 16px;
    border: none;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.modal-header {
    border-bottom: 1px solid #eee;
}

.modal-footer {
    border-top: 1px solid #eee;
}

.footer {
    margin-top: auto;
}

@media (max-width: 768px) {
    .display-5 {
        font-size: 1.75rem;
    }
    
    .icon-wrapper {
        font-size: 1.5rem;
    }
}