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

:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --accent-color: #e74c3c;
    --warning-color: #f39c12;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
    --text-dark: #2c3e50;
    --text-light: #7f8c8d;
    --bg-light: #f8f9fa;
    --bg-dark: #34495e;
    --shadow: 0 4px 6px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
}

/* 暗色主题变量 */
body.dark-theme {
    --text-dark: #ecf0f1;
    --text-light: #bdc3c7;
    --bg-light: #2c3e50;
    --bg-dark: #34495e;
    --shadow: 0 4px 6px rgba(0,0,0,0.3);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    transition: var(--transition);
}

body.dark-theme {
    background: linear-gradient(135deg, #2c3e50 0%, #3498db 100%);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    background: white;
    min-height: 100vh;
    box-shadow: var(--shadow);
    position: relative;
}

body.dark-theme .container {
    background: var(--bg-dark);
    color: var(--text-dark);
}

/* 导航栏样式 */
.navbar {
    background: linear-gradient(135deg, var(--dark-color) 0%, var(--primary-color) 100%);
    padding: 1rem 2rem;
    color: white;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
}

.nav-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.nav-header h1 {
    font-size: 1.8rem;
    font-weight: 300;
    margin: 0;
}

.nav-header h1 i {
    margin-right: 0.5rem;
    color: var(--secondary-color);
}

.theme-toggle button {
    background: rgba(255,255,255,0.2);
    border: 1px solid rgba(255,255,255,0.3);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
}

.theme-toggle button:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-2px);
}

.nav-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 0.5rem;
}

.nav-btn {
    padding: 0.8rem 1rem;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 8px;
    background: rgba(255,255,255,0.1);
    color: white;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.nav-btn:hover {
    background: rgba(255,255,255,0.2);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

.nav-btn.active {
    background: rgba(255,255,255,0.3);
    border-color: var(--secondary-color);
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

/* 页面样式 */
.page {
    display: none;
    padding: 2rem;
    animation: fadeInUp 0.6s ease;
}

.page.active {
    display: block;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.page-header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 2rem;
    background: linear-gradient(135deg, var(--light-color) 0%, white 100%);
    border-radius: 15px;
    box-shadow: var(--shadow);
}

body.dark-theme .page-header {
    background: linear-gradient(135deg, var(--bg-dark) 0%, #2c3e50 100%);
}

.page-header h2 {
    color: var(--dark-color);
    font-size: 2.2rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

body.dark-theme .page-header h2 {
    color: var(--text-dark);
}

.page-description {
    color: var(--text-light);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
}

/* 图表容器样式 */
.chart-container {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    border: 1px solid #e0e0e0;
    transition: var(--transition);
}

body.dark-theme .chart-container {
    background: var(--bg-dark);
    border-color: #4a6572;
}

.chart-container:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.chart-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--light-color);
}

body.dark-theme .chart-header {
    border-bottom-color: #4a6572;
}

.chart-title {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--dark-color);
}

body.dark-theme .chart-title {
    color: var(--text-dark);
}

.chart-actions {
    display: flex;
    gap: 0.5rem;
}

.action-btn {
    padding: 0.5rem 1rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
}

.action-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

/* 控制按钮样式 */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    margin: 1.5rem 0;
    padding: 1.5rem;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-radius: 10px;
    border-left: 4px solid var(--primary-color);
}

body.dark-theme .controls {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
}

.control-btn {
    padding: 0.8rem 1.2rem;
    background: white;
    color: var(--dark-color);
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

body.dark-theme .control-btn {
    background: #4a6572;
    color: var(--text-dark);
    border-color: #5d6d7e;
}

.control-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(52, 152, 219, 0.3);
}

.control-btn i {
    font-size: 0.9rem;
}

/* 图表区域 */
.chart {
    width: 100%;
    height: 500px;
    background: white;
    border-radius: 10px;
    border: 1px solid #e0e0e0;
    margin: 1rem 0;
}

body.dark-theme .chart {
    background: var(--bg-dark);
    border-color: #4a6572;
}

/* 分析洞察区域 */
.chart-insights {
    background: linear-gradient(135deg, #e8f4fd 0%, #d6eaf8 100%);
    padding: 1.5rem;
    border-radius: 10px;
    margin-top: 1.5rem;
    border-left: 4px solid var(--secondary-color);
}

body.dark-theme .chart-insights {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    border-left-color: var(--secondary-color);
}

.chart-insights h4 {
    color: var(--dark-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

body.dark-theme .chart-insights h4 {
    color: var(--text-dark);
}

.chart-insights p {
    color: var(--text-light);
    margin-bottom: 0.5rem;
    line-height: 1.5;
}

/* 数据导入页面特定样式 */
.data-import-container {
    display: grid;
    gap: 2rem;
}

.upload-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.upload-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
    border: 2px dashed #e0e0e0;
    transition: var(--transition);
}

body.dark-theme .upload-card {
    background: var(--bg-dark);
    border-color: #4a6572;
}

.upload-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.upload-header {
    text-align: center;
    margin-bottom: 1.5rem;
}

.upload-header i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.upload-header h3 {
    color: var(--dark-color);
    font-size: 1.5rem;
}

body.dark-theme .upload-header h3 {
    color: var(--text-dark);
}

.upload-area {
    border: 2px dashed #bdc3c7;
    border-radius: 10px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    background: #f8f9fa;
}

body.dark-theme .upload-area {
    background: #2c3e50;
    border-color: #5d6d7e;
}

.upload-area:hover {
    border-color: var(--primary-color);
    background: #e8f4fd;
}

body.dark-theme .upload-area:hover {
    background: #34495e;
}

.upload-area i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.upload-area p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.upload-btn {
    padding: 0.8rem 2rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.upload-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.file-info {
    margin-top: 1rem;
    padding: 1rem;
    background: #e8f4fd;
    border-radius: 8px;
    display: none;
}

body.dark-theme .file-info {
    background: #2c3e50;
}

.data-preview {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

body.dark-theme .data-preview {
    background: var(--bg-dark);
}

.data-preview h4 {
    color: var(--dark-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

body.dark-theme .data-preview h4 {
    color: var(--text-dark);
}

.preview-table {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 1.5rem;
    min-height: 200px;
    border: 1px solid #e0e0e0;
}

body.dark-theme .preview-table {
    background: #2c3e50;
    border-color: #4a6572;
}

.import-options {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

body.dark-theme .import-options {
    background: var(--bg-dark);
}

.import-options h4 {
    color: var(--dark-color);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

body.dark-theme .import-options h4 {
    color: var(--text-dark);
}

.options-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.option-card {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 10px;
    text-align: center;
    transition: var(--transition);
    border: 1px solid #e0e0e0;
}

body.dark-theme .option-card {
    background: #2c3e50;
    border-color: #4a6572;
}

.option-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    border-color: var(--primary-color);
}

.option-card i {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.option-card h5 {
    color: var(--dark-color);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

body.dark-theme .option-card h5 {
    color: var(--text-dark);
}

.option-card p {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    line-height: 1.4;
}

.option-btn {
    padding: 0.6rem 1.2rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

.option-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.api-section {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

body.dark-theme .api-section {
    background: var(--bg-dark);
}

.api-section h4 {
    color: var(--dark-color);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

body.dark-theme .api-section h4 {
    color: var(--text-dark);
}

.api-controls {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.api-input {
    flex: 1;
    min-width: 300px;
    padding: 0.8rem 1rem;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
}

body.dark-theme .api-input {
    background: #2c3e50;
    border-color: #4a6572;
    color: var(--text-dark);
}

.api-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.api-btn {
    padding: 0.8rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.api-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.api-btn.secondary {
    background: var(--secondary-color);
}

.api-btn.secondary:hover {
    background: #27ae60;
}

.api-response {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 1.5rem;
    border: 1px solid #e0e0e0;
    min-height: 100px;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

body.dark-theme .api-response {
    background: #2c3e50;
    border-color: #4a6572;
    color: var(--text-dark);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .container {
        margin: 0;
        border-radius: 0;
    }
    
    .upload-section {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .navbar {
        padding: 1rem;
    }
    
    .nav-header {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .nav-buttons {
        grid-template-columns: 1fr 1fr;
    }
    
    .page {
        padding: 1rem;
    }
    
    .chart-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }
    
    .controls {
        flex-direction: column;
    }
    
    .control-btn {
        width: 100%;
        justify-content: center;
    }
    
    .api-controls {
        flex-direction: column;
    }
    
    .api-input {
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .nav-buttons {
        grid-template-columns: 1fr;
    }
    
    .options-grid {
        grid-template-columns: 1fr;
    }
    
    .chart-container {
        padding: 1rem;
    }
    
    .page-header {
        padding: 1.5rem;
    }
    
    .page-header h2 {
        font-size: 1.8rem;
    }
}