/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header 样式 */
header {
    text-align: center;
    padding: 40px 20px;
    color: white;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* 上传区域样式 */
.upload-section {
    margin-bottom: 30px;
}

.upload-box {
    background: white;
    border-radius: 16px;
    padding: 60px 40px;
    text-align: center;
    border: 3px dashed #ddd;
    transition: all 0.3s ease;
    cursor: pointer;
}

.upload-box:hover {
    border-color: #667eea;
    background: #f8f9ff;
}

.upload-box.dragover {
    border-color: #667eea;
    background: #f0f4ff;
    transform: scale(1.02);
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.upload-box h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: #333;
}

.upload-box p {
    color: #666;
    margin-bottom: 20px;
}

.upload-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px 30px;
    font-size: 1rem;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.upload-btn:hover {
    transform: translateY(-2px);
}

/* 预览区域样式 */
.preview-section {
    background: white;
    border-radius: 16px;
    padding: 30px;
    margin-bottom: 30px;
}

.preview-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 30px;
}

.preview-box {
    text-align: center;
}

.preview-box h4 {
    margin-bottom: 15px;
    color: #333;
}

.preview-box img {
    max-width: 100%;
    max-height: 400px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.result-container {
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: repeating-conic-gradient(#fff 0 90deg, #eee 0 180deg) 0 0/20px 20px;
    border-radius: 8px;
}

/* Loading 样式 */
.loading {
    text-align: center;
}

.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 20px;
}

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

/* 按钮样式 */
.action-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
}

.btn {
    padding: 12px 30px;
    font-size: 1rem;
    border-radius: 8px;
    cursor: pointer;
    border: none;
    transition: all 0.2s ease;
}

.btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn.primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn.secondary {
    background: #f0f0f0;
    color: #333;
}

.btn:hover:not(:disabled) {
    transform: translateY(-2px);
}

/* 使用场景样式 */
.use-cases {
    margin-top: 40px;
    padding: 40px 20px;
}

.section-title {
    text-align: center;
    color: white;
    font-size: 2rem;
    margin-bottom: 40px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.use-case-card {
    background: white;
    border-radius: 16px;
    padding: 30px 25px;
    text-align: center;
    transition: all 0.3s ease;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.use-case-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.use-case-icon {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.use-case-card h3 {
    color: #333;
    font-size: 1.3rem;
    margin-bottom: 15px;
}

.use-case-card p {
    color: #666;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }
    
    .preview-container {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .use-cases-grid {
        grid-template-columns: 1fr;
    }
}