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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f7fa;
}

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

/* 头部样式 */
header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-size: 24px;
    font-weight: 600;
}

.logo i {
    margin-right: 10px;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

nav ul li a:hover {
    opacity: 0.8;
}

/* 主要内容 */
main {
    padding: 40px 0;
}

.intro {
    text-align: center;
    margin-bottom: 40px;
}

.intro h2 {
    font-size: 32px;
    margin-bottom: 15px;
    color: #2d3748;
}

.intro p {
    font-size: 18px;
    color: #718096;
    max-width: 800px;
    margin: 0 auto;
}

.calculator-wrapper {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    padding: 30px;
    margin-bottom: 40px;
}

.form-section {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid #e2e8f0;
}

.form-section:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.form-section h3 {
    font-size: 20px;
    margin-bottom: 20px;
    color: #2d3748;
    display: flex;
    align-items: center;
}

.form-section h3 i {
    margin-right: 10px;
    color: #667eea;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #4a5568;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    font-size: 16px;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.checkbox-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.checkbox-group label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-weight: 400;
}

.checkbox-group input {
    width: auto;
    margin-right: 10px;
}

.form-actions {
    text-align: center;
    margin-top: 30px;
}

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-block;
    margin: 0 10px;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background-color: #e2e8f0;
    color: #4a5568;
}

.btn-secondary:hover {
    background-color: #cbd5e0;
}

/* 结果样式 */
.result-section {
    margin-top: 40px;
    padding-top: 30px;
    border-top: 2px solid #e2e8f0;
}

.result-header {
    text-align: center;
    margin-bottom: 30px;
}

.result-header h3 {
    font-size: 24px;
    color: #2d3748;
    margin-bottom: 10px;
}

.result-header p {
    color: #718096;
}

.result-summary {
    margin-bottom: 30px;
}

.summary-item.total {
    text-align: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    border-radius: 12px;
    margin-bottom: 20px;
}

.summary-item.total h4 {
    font-size: 18px;
    margin-bottom: 10px;
    opacity: 0.9;
}

.summary-item.total .amount {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 5px;
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.summary-item {
    background: #f7fafc;
    padding: 20px;
    border-radius: 8px;
    text-align: center;
}

.summary-item h4 {
    font-size: 16px;
    color: #4a5568;
    margin-bottom: 10px;
}

.summary-item .amount {
    font-size: 24px;
    font-weight: 600;
    color: #2d3748;
}

.summary-item .amount.small {
    font-size: 20px;
}

.result-details {
    margin-bottom: 30px;
}

.result-details h4 {
    font-size: 18px;
    margin-bottom: 15px;
    color: #2d3748;
}

.cost-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.cost-table th,
.cost-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #e2e8f0;
}

.cost-table th {
    background-color: #f7fafc;
    font-weight: 600;
    color: #4a5568;
}

.cost-table tfoot td {
    font-weight: 600;
    background-color: #f7fafc;
}

.result-notice {
    background-color: #ebf8ff;
    border-left: 4px solid #4299e1;
    padding: 20px;
    border-radius: 0 8px 8px 0;
    margin-bottom: 30px;
}

.result-notice h4 {
    color: #2b6cb0;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
}

.result-notice h4 i {
    margin-right: 8px;
}

.result-notice ul {
    margin-left: 20px;
    color: #2d3748;
}

.result-notice li {
    margin-bottom: 8px;
}

.result-actions {
    text-align: center;
}

/* 功能特点 */
.features {
    margin-bottom: 40px;
}

.features h3 {
    text-align: center;
    font-size: 24px;
    margin-bottom: 30px;
    color: #2d3748;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-item {
    background: white;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s;
}

.feature-item:hover {
    transform: translateY(-5px);
}

.feature-item i {
    font-size: 40px;
    color: #667eea;
    margin-bottom: 20px;
}

.feature-item h4 {
    font-size: 18px;
    margin-bottom: 10px;
    color: #2d3748;
}

.feature-item p {
    color: #718096;
}

/* 小贴士 */
.tips {
    background: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    margin-bottom: 40px;
}

.tips h3 {
    font-size: 24px;
    margin-bottom: 20px;
    color: #2d3748;
}

.tips ul {
    margin-left: 20px;
}

.tips li {
    margin-bottom: 10px;
    color: #4a5568;
}

.tips strong {
    color: #2d3748;
}

/* 页脚 */
footer {
    background-color: #2d3748;
    color: white;
    padding: 40px 0 20px;
}

.footer-links {
    margin-bottom: 30px;
}

.footer-links h4 {
    font-size: 18px;
    margin-bottom: 20px;
    color: #e2e8f0;
}

.links-container {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
}

.links-container a {
    color: #a0aec0;
    text-decoration: none;
    transition: color 0.3s;
}

.links-container a:hover {
    color: white;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #4a5568;
    color: #a0aec0;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        text-align: center;
    }
    
    nav ul {
        margin-top: 15px;
        justify-content: center;
    }
    
    nav ul li {
        margin: 0 15px;
    }
    
    .intro h2 {
        font-size: 24px;
    }
    
    .calculator-wrapper {
        padding: 20px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .checkbox-group {
        grid-template-columns: 1fr 1fr;
    }
    
    .summary-grid {
        grid-template-columns: 1fr;
    }
    
    .summary-item.total .amount {
        font-size: 36px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .checkbox-group {
        grid-template-columns: 1fr;
    }
    
    .btn {
        display: block;
        width: 100%;
        margin: 10px 0;
    }
    
    .cost-table th,
    .cost-table td {
        padding: 10px;
        font-size: 14px;
    }
}