/* ==========================================================================
   海角社 (HaiJiao She) - 核心全局样式表
   版本: v2.4 资深老站长亲调优化版
   适用范围: index.html, resources.html, detail.html, community.html, about.html, contact.html
   ========================================================================== */

/* 1. CSS 重置与基础变量定义 */
:root {
    --primary-color: #2b6cb0;
    --primary-hover: #2c5282;
    --accent-color: #dd6b20;
    --text-main: #2d3748;
    --text-muted: #718096;
    --bg-body: #f7fafc;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
    --radius: 6px;
    --max-width: 1200px;
    --transition: all 0.25s ease-in-out;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    font-size: 15px;
}

/* 2. 排版与通用工具 */
h1, h2, h3, h4, h5, h6 {
    color: #1a202c;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 0.75rem;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.2rem; }

p {
    margin-bottom: 1rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

ul {
    list-style: none;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.badge {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 4px;
    background-color: #edf2f7;
    color: var(--text-muted);
}

.badge-accent {
    background-color: #fffaf0;
    color: var(--accent-color);
}

.badge-primary {
    background-color: #ebf8ff;
    color: var(--primary-color);
}

/* 3. 头部导航设计 (Header & Nav) */
.site-header {
    background-color: #ffffff;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-sm);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo a {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
    text-decoration: none;
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--accent-color);
}

.main-nav ul {
    display: flex;
    gap: 25px;
    align-items: center;
}

.main-nav a {
    color: var(--text-main);
    font-weight: 500;
    font-size: 0.95krem;
    padding: 5px 0;
    position: relative;
    text-decoration: none;
}

.main-nav a:hover,
.main-nav a.active {
    color: var(--primary-color);
}

.main-nav a.active::after {
    content: '';
    position: absolute;
    bottom: -22px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
}

/* 4. 页面主体与区块网格布局 */
main {
    min-height: calc(100vh - 70px - 160px);
    padding: 40px 0;
}

.section-title {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    margin-bottom: 25px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.grid-2 {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

/* 5. 卡片组件 (Cards & Lists) */
.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.resource-card h3 a {
    color: var(--text-main);
}
.resource-card h3 a:hover {
    color: var(--primary-color);
}

.meta-info {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin: 10px 0;
    display: flex;
    gap: 15px;
}

/* 6. 表单与按钮样式 (Forms & Buttons) */
.btn {
    display: inline-block;
    padding: 10px 20px;
    background-color: var(--primary-color);
    color: #ffffff;
    font-weight: 600;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
    text-decoration: none;
}

.btn:hover {
    background-color: var(--primary-hover);
    color: #ffffff;
    text-decoration: none;
}

.btn-accent {
    background-color: var(--accent-color);
}
.btn-accent:hover {
    background-color: #c05621;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
}

.form-control {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-size: 1rem;
    font-family: inherit;
    background-color: #fff;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(43, 108, 176, 0.15);
}

textarea.form-control {
    resize: vertical;
    min-height: 120px;
}

/* 7. 公告提示条与老站长温馨提示框 */
.notice-box {
    background-color: #fffaf0;
    border-left: 4px solid var(--accent-color);
    padding: 15px;
    border-radius: 0 var(--radius) var(--radius) 0;
    margin-bottom: 25px;
    font-size: 0.95rem;
}

.notice-box p:last-child {
    margin-bottom: 0;
}

/* 8. 详情页专用样式 */
.detail-header {
    background: #fff;
    padding: 30px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 30px;
}

.download-box {
    background: #ebf8ff;
    border: 1px dashed var(--primary-color);
    padding: 20px;
    border-radius: var(--radius);
    margin: 25px 0;
    text-align: center;
}

/* 9. 页脚样式 (Footer) */
.site-footer {
    background-color: #1a202c;
    color: #a0aec0;
    padding: 40px 0 20px;
    font-size: 0.9rem;
}

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

.footer-content h4 {
    color: #ffffff;
    margin-bottom: 15px;
}

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: #a0aec0;
}

.footer-links a:hover {
    color: #ffffff;
}

.footer-bottom {
    border-top: 1px solid #2d3748;
    padding-top: 20px;
    text-align: center;
    font-size: 0.85rem;
}

/* 10. 响应式微调 */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        height: auto;
        padding: 15px 0;
    }
    
    .main-nav ul {
        margin-top: 10px;
        gap: 15px;
    }

    .grid-2 {
        grid-template-columns: 1fr;
    }
    
    .main-nav a.active::after {
        display: none;
    }
}