* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 500px;
}

.card {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

h1 {
    font-size: 28px;
    color: #333;
    margin-bottom: 10px;
    text-align: center;
}

.subtitle {
    color: #666;
    text-align: center;
    margin-bottom: 30px;
    font-size: 14px;
}

.upload-area {
    border: 2px dashed #667eea;
    border-radius: 12px;
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: #f8f9ff;
}

.upload-area:hover {
    border-color: #764ba2;
    background: #f0f2ff;
}

.upload-area.dragover {
    border-color: #764ba2;
    background: #e8ebff;
    transform: scale(1.02);
}

.upload-icon {
    color: #667eea;
    margin-bottom: 15px;
}

.upload-text {
    color: #666;
    font-size: 14px;
}

.file-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px;
    background: #f8f9ff;
    border-radius: 12px;
    margin-bottom: 20px;
}

.file-details {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #333;
}

.file-details svg {
    color: #667eea;
}

.btn-remove {
    background: #ff4757;
    color: white;
    border: none;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.btn-remove:hover {
    background: #ff3838;
    transform: scale(1.1);
}

.btn-convert {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-convert:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.4);
}

.btn-convert:active {
    transform: translateY(0);
}

.loading {
    text-align: center;
    padding: 30px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading p {
    color: #666;
    font-size: 14px;
}

.success {
    text-align: center;
    padding: 30px;
}

.success svg {
    color: #2ecc71;
    margin-bottom: 15px;
}

.success p {
    color: #2ecc71;
    font-size: 18px;
    font-weight: 600;
}

.hidden {
    display: none;
}