/* General Setup / 基础设置 */
body {
    font-family: system-ui, -apple-system, sans-serif;
    background-color: #f0f4f8;
    color: #2d3748;
    padding: 2rem;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

/* Hide the logic inputs / 隐藏逻辑输入框 */
.tab-logic {
    display: none;
}

/* Tab List Styling / 选项卡列表样式 */
.tab-list {
    display: flex;
    border-bottom: 2px solid #cbd5e0;
    margin-bottom: -2px; /* Prevent double borders / 防止双边框 */
}

.tab-button {
    padding: 12px 24px;
    cursor: pointer;
    background: #edf2f7;
    margin-right: 4px;
    border: 2px solid #cbd5e0;
    border-bottom: none;
    border-radius: 8px 8px 0 0;
    font-weight: 600;
    transition: background 0.2s, color 0.2s;
}

.tab-button:hover {
    background: #e2e8f0;
}

/* Content Panels / 内容面板样式 */
.tab-panels {
    background: #ffffff;
    border: 2px solid #cbd5e0;
    border-radius: 0 8px 8px 8px;
    padding: 2rem;
    min-height: 200px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.tab-panel {
    display: none; /* Hidden by default / 默认隐藏 */
}

/* THE LOGIC: Sibling Selectors / 核心逻辑：兄弟选择器
   When input is checked, find the label and the panel to show.
*/

/* Highlight the active label / 高亮选中的标签 */
#tab-1:checked ~ .tab-list label[for="tab-1"],
#tab-2:checked ~ .tab-list label[for="tab-2"],
#tab-3:checked ~ .tab-list label[for="tab-3"] {
    background: #ffffff;
    color: #3182ce;
    border-bottom-color: #ffffff;
    padding-bottom: 14px; /* Cover the border below / 覆盖下方的边框 */
    margin-bottom: -2px;
}

/* Show the active panel / 显示选中的面板 */
#tab-1:checked ~ .tab-panels #panel-1,
#tab-2:checked ~ .tab-panels #panel-2,
#tab-3:checked ~ .tab-panels #panel-3 {
    display: block;
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Explanation Section / 说明部分 */
.explanation {
    margin-top: 3rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    padding-top: 2rem;
    border-top: 1px solid #cbd5e0;
}

@media (max-width: 640px) {
    .explanation {
        grid-template-columns: 1fr;
    }
    .tab-list {
        flex-direction: column;
    }
    .tab-button {
        border-radius: 8px;
        margin-bottom: 4px;
        border-bottom: 2px solid #cbd5e0;
    }
}
/* SEO Insight Box Styling / SEO 见解区块样式 */
.seo-insight-box {
    margin: 3rem 0;
    padding: 2rem;
    background: #ffffff;
    border-radius: 12px;
    border: 2px solid #cbd5e0;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.seo-insight-box h2 {
    color: #3182ce; /* Matches your accent color */
    font-size: 1.4rem;
    margin-top: 0;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid #edf2f7;
    padding-bottom: 0.5rem;
    text-align: left;
}

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

.seo-insight-box article h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: #2d3748;
}

.seo-insight-box p {
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 1rem;
    color: #4a5568;
}

.seo-insight-box p[lang="zh"] {
    color: #718096;
    font-size: 0.85rem;
    border-left: 3px solid #ebf8ff;
    padding-left: 1rem;
}

@media (max-width: 600px) {
    .insight-grid { grid-template-columns: 1fr; }
}

/* Footer Styling */
.pattern-footer {
    max-width: 1000px;
    margin: 4rem auto;
    padding: 2rem 1rem;
    text-align: center;
}

.back-nav a {
    color: var(--accent-blue);
    text-decoration: none;
    font-weight: 600;
}

.corporate-links {
    margin-top: 2rem;
    font-size: 0.9rem;
    color: #64748b;
}

.corporate-links a {
    color: var(--accent-blue);
    text-decoration: none;
}

@media (max-width: 768px) {
    .insight-grid { grid-template-columns: 1fr; }
}