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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 20px auto;
    padding: 30px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
}

h1 {
    text-align: center;
    color: #4a5568;
    margin-bottom: 35px;
    font-size: 2.8em;
    font-weight: 700;
    letter-spacing: -0.5px;
}

h2 {
    color: #2d3748;
    margin-bottom: 20px;
    font-size: 1.5em;
    font-weight: 600;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 12px;
}

/* 上传区域样式 */
.upload-section {
    margin-bottom: 40px;
}

.upload-area {
    border: 2px dashed #cbd5e0;
    border-radius: 10px;
    padding: 20px 30px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.05);
    max-width: 500px;
    margin: 0 auto;
}

.upload-area:hover {
    border-color: #667eea;
    background: linear-gradient(135deg, #edf2f7 0%, #e2e8f0 100%);
    transform: translateY(-2px);
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.08);
}

.upload-area.dragover {
    border-color: #667eea;
    background: linear-gradient(135deg, #edf2f7 0%, #e2e8f0 100%);
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.08);
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.upload-icon {
    font-size: 2.5em;
    color: #a0aec0;
    transition: transform 0.3s ease;
}

.upload-area:hover .upload-icon {
    transform: scale(1.05);
}

.upload-content p {
    font-size: 1em;
    color: #4a5568;
    font-weight: 500;
    margin: 0;
}

.upload-hint {
    font-size: 0.8em !important;
    color: #718096 !important;
    font-weight: 400 !important;
    margin: 0 !important;
}

.file-info {
    margin-top: 15px;
    padding: 10px 20px;
    background: linear-gradient(135deg, #e6fffa 0%, #b2f5ea 100%);
    border: 1px solid #81e6d9;
    border-radius: 6px;
    color: #2c7a7b;
    font-weight: 500;
    font-size: 0.9em;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
    max-width: 500px;
    margin: 15px auto 0;
}

/* 按钮区域样式 */
.button-section {
    margin-bottom: 40px;
}

.buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    align-items: center;
    background: #f7fafc;
    padding: 20px;
    border-radius: 10px;
    border: 1px solid #e2e8f0;
}

button {
    padding: 14px 28px;
    font-size: 1em;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    min-width: 140px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

button:hover:not(:disabled) {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

button:active:not(:disabled) {
    transform: translateY(-1px);
}

button:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* 按钮颜色方案 */
button:nth-child(1) {
    background: linear-gradient(135deg, #4299e1 0%, #3182ce 100%);
    color: white;
}

button:nth-child(1):hover:not(:disabled) {
    background: linear-gradient(135deg, #3182ce 0%, #2b6cb0 100%);
}

button:nth-child(2) {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

button:nth-child(2):hover:not(:disabled) {
    background: linear-gradient(135deg, #38a169 0%, #2f855a 100%);
}

button:nth-child(3) {
    background: linear-gradient(135deg, #9f7aea 0%, #805ad5 100%);
    color: white;
}

button:nth-child(3):hover:not(:disabled) {
    background: linear-gradient(135deg, #805ad5 0%, #6b46c1 100%);
}

button:nth-child(4) {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
    color: white;
}

button:nth-child(4):hover:not(:disabled) {
    background: linear-gradient(135deg, #e53e3e 0%, #c53030 100%);
}

/* 预览区域样式 */
.preview-section {
    margin-bottom: 40px;
}

.tabs {
    display: flex;
    gap: 15px;
    margin-bottom: 25px;
    background: #f7fafc;
    padding: 8px;
    border-radius: 10px;
    border: 1px solid #e2e8f0;
}

.tab-btn {
    padding: 12px 30px;
    background: transparent;
    color: #718096;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    min-width: 140px;
    transition: all 0.3s ease;
    box-shadow: none;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 0.95em;
}

.tab-btn:hover {
    color: #667eea;
    background: #edf2f7;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.tab-btn.active {
    color: white;
    background: linear-gradient(135deg, #667eea 0%, #5a67d8 100%);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.tab-content {
    background: #f7fafc;
    border-radius: 10px;
    overflow: hidden;
    border: 1px solid #e2e8f0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.tab-pane {
    padding: 0;
}

.table-container {
    overflow-x: auto;
    max-height: 500px;
    overflow-y: auto;
    background: white;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 1em;
    background: white;
}

th, td {
    padding: 16px 20px;
    text-align: left;
    border-bottom: 1px solid #e2e8f0;
    border-right: 1px solid #e2e8f0;
    word-break: break-word;
}

th {
    background: linear-gradient(135deg, #edf2f7 0%, #e2e8f0 100%);
    font-weight: 600;
    position: sticky;
    top: 0;
    z-index: 20;
    color: #4a5568;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 0.9em;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

th:last-child, td:last-child {
    border-right: none;
}

tr:nth-child(even) {
    background: #f7fafc;
}

tr:hover {
    background: linear-gradient(135deg, #edf2f7 0%, #e2e8f0 100%);
    transform: scale(1.002);
    transition: background 0.2s ease;
}

td {
    color: #2d3748;
    font-size: 0.95em;
}

/* 统计信息样式 */
.stats-section {
    margin-bottom: 20px;
    background: #f7fafc;
    padding: 30px;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 25px;
}

.stat-item {
    background: linear-gradient(135deg, white 0%, #f7fafc 100%);
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

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

.stat-label {
    font-size: 1em;
    color: #718096;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin: 0;
}

.stat-value {
    font-size: 2.5em;
    font-weight: 700;
    color: #667eea;
    margin: 0;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        margin: 15px;
        padding: 25px;
    }
    
    h1 {
        font-size: 2.2em;
        margin-bottom: 30px;
    }
    
    h2 {
        font-size: 1.3em;
    }
    
    .upload-area {
        padding: 40px 20px;
    }
    
    .upload-icon {
        font-size: 4em;
    }
    
    .upload-content p {
        font-size: 1.1em;
    }
    
    .buttons {
        flex-direction: column;
        gap: 15px;
        padding: 15px;
    }
    
    button {
        width: 100%;
        min-width: auto;
        padding: 14px 20px;
        font-size: 1em;
    }
    
    .tabs {
        flex-direction: column;
        gap: 10px;
        padding: 10px;
    }
    
    .tab-btn {
        width: 100%;
        min-width: auto;
        padding: 12px 20px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .stats-section {
        padding: 20px;
    }
    
    th, td {
        padding: 12px 15px;
        font-size: 0.9em;
    }
}

/* 滚动条样式 */
.table-container::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

.table-container::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 5px;
}

.table-container::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #cbd5e0 0%, #a0aec0 100%);
    border-radius: 5px;
    border: 2px solid #f1f1f1;
}

.table-container::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #a0aec0 0%, #718096 100%);
}

/* 加载动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.container {
    animation: fadeIn 0.6s ease-out;
}

/* 链接样式 */
a {
    color: #667eea;
    text-decoration: none;
    transition: all 0.3s ease;
    border-bottom: 1px solid transparent;
}

a:hover {
    color: #5a67d8;
    border-bottom: 1px solid #5a67d8;
}