/* ==================== 全局样式 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #10b981;
    --accent-color: #8b5cf6;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-color: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB',
                 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

/* ==================== 页面标题 ==================== */
.header {
    text-align: center;
    margin-bottom: 30px;
}

.header h1 {
    font-size: 2rem;
    color: var(--text-color);
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* ==================== 主内容区布局 ==================== */
.main-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 30px;
}

/* ==================== 输入参数区 ==================== */
.input-section,
.result-section {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.input-section h2,
.result-section h2 {
    font-size: 1.25rem;
    margin-bottom: 20px;
    color: var(--text-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

/* 表单组 */
.form-group {
    margin-bottom: 24px;
}

.form-group h3 {
    font-size: 1rem;
    color: var(--text-color);
    margin-bottom: 12px;
    font-weight: 600;
}

/* 表单行 */
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 12px;
}

.form-item {
    display: flex;
    flex-direction: column;
}

.form-item.full-width {
    grid-column: 1 / -1;
}

/* 表单标签 */
label {
    font-size: 0.875rem;
    color: var(--text-color);
    margin-bottom: 6px;
    font-weight: 500;
}

/* 表单控件 */
.form-control {
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.9rem;
    color: var(--text-color);
    background-color: #fff;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* 自动计算字段区 */
.auto-calc-group {
    background-color: #f1f5f9;
    padding: 16px;
    border-radius: 8px;
}

.auto-calc-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.auto-calc-item {
    display: flex;
    flex-direction: column;
}

.auto-calc-item label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.auto-calc-value {
    padding: 8px 12px;
    background-color: #e2e8f0;
    border-radius: 4px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-color);
    text-align: center;
}

/* 按钮 */
.btn-primary {
    width: 100%;
    padding: 14px 24px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-primary:active {
    transform: scale(0.98);
}

/* ==================== 计算结果区 ==================== */
.result-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}

.result-card {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    border: 1px solid var(--border-color);
}

.result-card.highlight {
    background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%);
    border-color: var(--primary-color);
}

.result-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.result-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
    margin-bottom: 8px;
}

.result-card.highlight .result-value {
    color: var(--primary-color);
    font-size: 1.75rem;
}

.result-note {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* 计算说明 */
.calc-explanation {
    background-color: #f8fafc;
    padding: 16px;
    border-radius: 8px;
    margin-bottom: 20px;
}

.calc-explanation h4 {
    font-size: 0.9rem;
    color: var(--text-color);
    margin-bottom: 12px;
}

.formula {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
    line-height: 1.8;
}

/* 图表容器 */
.charts-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.chart-wrapper {
    background-color: #fff;
    padding: 16px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.chart-wrapper h3 {
    font-size: 0.9rem;
    color: var(--text-color);
    margin-bottom: 12px;
    text-align: center;
}

/* ==================== 对比分析区 ==================== */
.comparison-section {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.comparison-section h2 {
    font-size: 1.25rem;
    color: var(--text-color);
    margin-bottom: 20px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

/* 对比表格 */
.comparison-table-container {
    overflow-x: auto;
    margin-bottom: 24px;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

.comparison-table th,
.comparison-table td {
    padding: 12px 16px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.comparison-table th {
    background-color: #f8fafc;
    font-weight: 600;
    color: var(--text-color);
}

.comparison-table tbody tr:hover {
    background-color: #f8fafc;
}

.comparison-table .current-row {
    background-color: #dbeafe;
    font-weight: 600;
}

.comparison-table .positive-diff {
    color: var(--secondary-color);
}

.comparison-table .negative-diff {
    color: #ef4444;
}

/* 趋势图表 */
.trend-chart-container {
    background-color: #fff;
    padding: 20px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.trend-chart-container h3 {
    font-size: 0.9rem;
    color: var(--text-color);
    margin-bottom: 16px;
    text-align: center;
}

/* ==================== 累计领取预测区 ==================== */
.cumulative-section {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.cumulative-section h2 {
    font-size: 1.25rem;
    color: var(--text-color);
    margin-bottom: 8px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.section-desc {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 20px;
}

.cumulative-container {
    animation: fadeIn 0.3s ease-out;
}

.cumulative-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.cumulative-card {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    border: 1px solid #fbbf24;
    transition: transform 0.2s, box-shadow 0.2s;
}

.cumulative-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(251, 191, 36, 0.2);
}

.cumulative-age {
    font-size: 1rem;
    font-weight: 600;
    color: #92400e;
    margin-bottom: 12px;
}

.cumulative-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: #78350f;
    margin-bottom: 8px;
}

.cumulative-years {
    font-size: 0.8rem;
    color: #a16207;
}

/* ==================== 页脚 ==================== */
.footer {
    text-align: center;
    padding: 20px;
    color: var(--text-secondary);
    font-size: 0.8rem;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 1fr;
    }

    .result-cards {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    body {
        padding: 12px;
    }

    .header h1 {
        font-size: 1.5rem;
    }

    .subtitle {
        font-size: 0.875rem;
    }

    .input-section,
    .result-section,
    .comparison-section {
        padding: 16px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .auto-calc-grid {
        grid-template-columns: 1fr;
    }

    .result-cards {
        grid-template-columns: 1fr;
    }

    .cumulative-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .charts-container {
        grid-template-columns: 1fr;
    }

    .result-value {
        font-size: 1.25rem;
    }

    .result-card.highlight .result-value {
        font-size: 1.5rem;
    }

    .comparison-table {
        font-size: 0.75rem;
    }

    .comparison-table th,
    .comparison-table td {
        padding: 8px 10px;
    }
}

@media (max-width: 480px) {
    .header h1 {
        font-size: 1.25rem;
    }

    .input-section h2,
    .result-section h2,
    .comparison-section h2 {
        font-size: 1.1rem;
    }

    .form-control {
        padding: 8px 10px;
        font-size: 0.85rem;
    }

    .btn-primary {
        padding: 12px 20px;
        font-size: 0.9rem;
    }
}

/* ==================== 隐藏状态 ==================== */
[style*="display: none"] {
    display: none !important;
}

/* ==================== 动画 ==================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-cards,
.charts-container,
.comparison-table-container,
.trend-chart-container {
    animation: fadeIn 0.3s ease-out;
}