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

body {
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
    background: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

header {
    background: #2c3e50;
    color: white;
    padding: 2rem 0;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.nav-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    background: #34495e;
    color: white;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    font-weight: 500;
}

.nav-btn:hover {
    background: #3498db;
    transform: translateY(-2px);
}

.nav-btn.active {
    background: #3498db;
}

.data-controls {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.data-btn {
    padding: 0.6rem 1.2rem;
    border: none;
    background: #27ae60;
    color: white;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.85rem;
    font-weight: 500;
}

.data-btn:hover {
    background: #229954;
    transform: translateY(-2px);
}

header h1 {
    font-size: 2.5rem;
    font-weight: 300;
    margin: 0;
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

.chart-section {
    background: white;
    margin-bottom: 3rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    display: none;
    animation: fadeIn 0.5s ease-in-out;
}

.chart-section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.chart-section h2 {
    background: #3498db;
    color: white;
    padding: 1rem 2rem;
    margin: 0;
    font-size: 1.3rem;
    font-weight: 400;
}

.chart-container {
    padding: 2rem;
    height: 500px;
    position: relative;
}

footer {
    background: #34495e;
    color: white;
    text-align: center;
    padding: 2rem;
    margin-top: 3rem;
}

/* 数据面板样式 */
.data-panel {
    background: white;
    margin-bottom: 3rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    display: none;
    animation: fadeIn 0.5s ease-in-out;
}

.data-panel.active {
    display: block;
}

.input-container {
    padding: 2rem;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #2c3e50;
}

.input-group input,
.input-group select,
.input-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 0.9rem;
    transition: border-color 0.3s ease;
}

.input-group input:focus,
.input-group select:focus,
.input-group textarea:focus {
    outline: none;
    border-color: #3498db;
}

.input-group textarea {
    min-height: 80px;
    resize: vertical;
}

.button-group {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

.submit-btn {
    padding: 0.75rem 2rem;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.submit-btn:hover {
    background: #2980b9;
}

.cancel-btn {
    padding: 0.75rem 2rem;
    background: #95a5a6;
    color: white;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.cancel-btn:hover {
    background: #7f8c8d;
}

.excel-preview {
    margin-top: 2rem;
    padding: 1rem;
    background: #f8f9fa;
    border-radius: 5px;
}

.excel-preview table {
    width: 100%;
    border-collapse: collapse;
}

.excel-preview th,
.excel-preview td {
    border: 1px solid #ddd;
    padding: 0.5rem;
    text-align: left;
}

.excel-preview th {
    background: #3498db;
    color: white;
}

.style-options {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.style-options label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    main {
        padding: 1rem;
    }
    
    .chart-section h2 {
        font-size: 1.1rem;
        padding: 1rem;
    }
    
    .chart-container {
        padding: 1rem;
        height: 400px;
    }
    
    .data-controls,
    .nav {
        flex-direction: column;
        align-items: center;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .style-options {
        flex-direction: column;
    }
}