/**
 * style.css - 核心公共样式
 * 林草生态技术系网站
 * 包含所有页面共用的样式定义
 */

/* =========================================
   1. CSS变量定义
   ========================================= */
:root {
    /* 颜色系统 */
    --color-primary: #4A7C59;      /* 中绿-主色 */
    --color-primary-dark: #2D5F3D; /* 深绿-链接/标题 */
    --color-primary-light: #90C590; /* 浅绿-次色 */
    --color-accent: #E67E22;       /* 橙色-强调 */
    --color-bg: #FFFFFF;           /* 白色背景 */
    --color-bg-alt: #F7FAF7;      /* 极浅绿背景 */
    --color-bg-section: #F0F5F0;  /* 模块背景 */
    --color-text: #333333;         /* 正文文字 */
    --color-text-light: #666666;   /* 辅助文字 */
    --color-text-muted: #999999;   /* 更浅的文字 */
    --color-border: #E0E8E0;       /* 边框色 */
    --color-white: #FFFFFF;
    
    /* 字体系统 - 使用clamp()实现流体字体缩放 */
    --font-family: "Microsoft YaHei", "微软雅黑", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
    /* 基础字体大小：最小14px，随视口缩放，最大18px */
    --font-size-base: clamp(14px, 0.9vw + 6px, 18px);
    /* 小号字体：最小12px，最大15px */
    --font-size-sm: clamp(12px, 0.7vw + 5px, 15px);
    /* 大号字体：最小16px，最大20px */
    --font-size-lg: clamp(16px, 1vw + 6px, 20px);
    /* 超大字体：最小18px，最大24px */
    --font-size-xl: clamp(18px, 1.1vw + 7px, 24px);
    /* 特大字体：最小24px，最大32px */
    --font-size-xxl: clamp(24px, 1.5vw + 8px, 32px);
    /* 标题字体：最小20px，最大26px */
    --font-size-title: clamp(20px, 1.2vw + 7px, 26px);
    
    /* 布局尺寸 */
    --container-width: 1200px;
    --sidebar-width: 240px;
    --header-height: 60px;
    --gap: 20px;
    --radius: 4px;
    
    /* 效果 */
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-hover: 0 4px 16px rgba(0,0,0,0.12);
    --transition: all 0.3s ease;
}

/* =========================================
   2. 基础样式
   ========================================= */
html {
    font-size: clamp(14px, 0.9vw + 6px, 18px);
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.6;
}

/* =========================================
   3. 通用布局类
   ========================================= */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 15px;
}

.clearfix::after {
    content: '';
    display: table;
    clear: both;
}

/* Flex布局 */
.flex {
    display: flex;
}

.flex-center {
    display: flex;
    justify-content: center;
    align-items: center;
}

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

.flex-start {
    display: flex;
    justify-content: flex-start;
    align-items: center;
}

.flex-end {
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-column {
    flex-direction: column;
}

.flex-1 {
    flex: 1;
}

/* 文本对齐 */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

/* 显示/隐藏 */
.hidden {
    display: none !important;
}

.visible {
    display: block;
}

/* 间距辅助类 */
.mt-10 { margin-top: 10px; }
.mt-20 { margin-top: 20px; }
.mt-30 { margin-top: 30px; }
.mb-10 { margin-bottom: 10px; }
.mb-20 { margin-bottom: 20px; }
.mb-30 { margin-bottom: 30px; }
.pt-10 { padding-top: 10px; }
.pt-20 { padding-top: 20px; }
.pb-10 { padding-bottom: 10px; }
.pb-20 { padding-bottom: 20px; }

/* =========================================
   4. 顶部条样式 (.top-bar) - 已移除
   ========================================= */
/* .top-bar 已根据用户要求移除，相关样式已注释 */

/* =========================================
   5. 主导航栏样式 (.main-header)
   ========================================= */
.main-header {
    background-color: var(--color-white);
    height: 70px;
    border-bottom: 2px solid var(--color-primary-light);
    position: relative;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

/* Logo区域 */
.logo-area {
    display: flex;
    align-items: center;
}

.logo-area .logo {
    width: 40px;
    height: 40px;
    margin-right: 12px;
    background-color: var(--color-primary);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    font-weight: bold;
}

.logo-area .site-name {
    font-size: clamp(18px, 1.2vw + 6px, 24px);
    font-weight: bold;
    color: var(--color-primary);
}

/* 主导航菜单 */
.main-nav {
    display: flex;
    align-items: center;
}

.main-nav > ul {
    display: flex;
    align-items: center;
}

.main-nav > ul > li {
    position: relative;
}

.main-nav > ul > li > a {
    display: block;
    padding: 0 18px;
    font-size: var(--font-size-base);
    color: var(--color-text);
    line-height: 70px;
    transition: var(--transition);
    position: relative;
}

.main-nav > ul > li > a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition);
}

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

.main-nav > ul > li > a:hover::after,
.main-nav > ul > li.active > a::after {
    width: 80%;
}

/* 下拉子菜单 */
.main-nav .sub-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 160px;
    background-color: var(--color-white);
    box-shadow: var(--shadow);
    border-radius: 0 0 var(--radius) var(--radius);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition);
    z-index: 200;
}

.main-nav > ul > li:hover .sub-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.main-nav .sub-menu li a {
    display: block;
    padding: 12px 20px;
    font-size: var(--font-size-base);
    color: var(--color-text);
    border-bottom: 1px solid var(--color-border);
    transition: var(--transition);
}

.main-nav .sub-menu li:last-child a {
    border-bottom: none;
}

.main-nav .sub-menu li a:hover {
    background-color: var(--color-bg-alt);
    color: var(--color-primary);
}

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    cursor: pointer;
    padding: 8px;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    margin: 3px 0;
    transition: var(--transition);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* =========================================
   6. 面包屑导航 (.breadcrumb)
   ========================================= */
.breadcrumb {
    font-size: var(--font-size-sm);
    display: flex;
    align-items: center;
    flex-wrap: wrap;
}

.breadcrumb-label {
    color: var(--color-text-light);
    margin-right: 4px;
}

.breadcrumb a {
    color: var(--color-primary);
    transition: var(--transition);
}

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

.breadcrumb .separator {
    margin: 0 4px;
    color: var(--color-text-muted);
}

.breadcrumb .current {
    color: var(--color-text-light);
}

/* 内容头部区域 - 用于放置面包屑 */
.content-header {
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

/* 列表头部区域 - 标题和面包屑并排 */
.list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

/* =========================================
   7. 内容区布局
   ========================================= */
.main-content {
    padding: var(--gap) 0;
}

.content-wrapper {
    display: flex;
    gap: var(--gap);
}

.content-left {
    flex: 1;
    min-width: 0;
}

.content-right {
    width: var(--sidebar-width);
    flex-shrink: 0;
}

/* =========================================
   8. 侧边栏导航 (.sidebar)
   ========================================= */
.sidebar {
    width: var(--sidebar-width);
}

.sidebar-title {
    background-color: var(--color-primary);
    color: var(--color-white);
    padding: 15px;
    font-size: var(--font-size-xl);
    font-weight: bold;
}

.sidebar-menu {
    background-color: var(--color-white);
    border: 1px solid var(--color-border);
    border-top: none;
}

.sidebar-menu li {
    border-bottom: 1px solid var(--color-border);
}

.sidebar-menu li:last-child {
    border-bottom: none;
}

.sidebar-menu li a {
    display: block;
    padding: 12px 20px;
    color: var(--color-text);
    font-size: var(--font-size-base);
    transition: var(--transition);
    border-left: 3px solid transparent;
}

.sidebar-menu li a:hover,
.sidebar-menu li.active a {
    background-color: var(--color-bg-alt);
    color: var(--color-primary);
    border-left-color: var(--color-primary);
}

/* 侧边栏子菜单 */
.sidebar-menu li .sub-items {
    display: none;
    background-color: var(--color-bg-alt);
}

.sidebar-menu li.open .sub-items {
    display: block;
}

.sidebar-menu li .sub-items a {
    padding-left: 40px;
    font-size: var(--font-size-sm);
}

/* =========================================
   9. 页脚样式 (.footer)
   ========================================= */
.footer {
    background-color: #2D5F3D;
    color: var(--color-white);
    margin-top: 40px;
    padding: 30px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 30px;
}

/* 左侧：版权信息 */
.footer-left {
    flex: 1;
    text-align: left;
}

.footer-left p {
    font-size: var(--font-size-sm);
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
    margin: 0;
}

/* 中间：联系方式 */
.footer-center {
    flex: 1.5;
    text-align: center;
}

.footer-center p {
    font-size: var(--font-size-sm);
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
    margin: 0;
}

/* 右侧：事业单位标识 */
.footer-right {
    flex: 0.8;
    text-align: right;
}

.footer-right a {
    display: inline-block;
}

.footer-right img {
    width: 80px;
    height: auto;
    opacity: 0.9;
    transition: opacity 0.3s ease;
}

.footer-right img:hover {
    opacity: 1;
}

/* 移动端响应式 */
@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
        gap: 20px;
    }
    
    .footer-left,
    .footer-center,
    .footer-right {
        flex: none;
        width: 100%;
        text-align: center;
    }
    
    .footer-right img {
        width: 60px;
    }
}

/* =========================================
   10. 分页器 (.pagination)
   ========================================= */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    margin: 30px 0;
}

.pagination a,
.pagination span {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    min-width: 36px;
    height: 36px;
    padding: 0 10px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    font-size: var(--font-size-base);
    color: var(--color-text);
    background-color: var(--color-white);
    transition: var(--transition);
}

.pagination a:hover {
    background-color: var(--color-primary-light);
    border-color: var(--color-primary-light);
    color: var(--color-white);
}

.pagination .active {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-white);
}

.pagination .disabled {
    color: var(--color-text-muted);
    cursor: not-allowed;
}

.pagination .disabled:hover {
    background-color: var(--color-white);
    border-color: var(--color-border);
    color: var(--color-text-muted);
}

.pagination .prev,
.pagination .next {
    padding: 0 15px;
}

.pagination .ellipsis {
    border: none;
    background: transparent;
}

/* =========================================
   11. 通用组件
   ========================================= */

/* 模块标题 */
.section-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 15px;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--color-border);
}

.section-title .title {
    display: flex;
    align-items: center;
    font-size: var(--font-size-title);
    font-weight: bold;
    color: var(--color-text);
}

.section-title .title::before {
    content: '';
    display: inline-block;
    width: 3px;
    height: 20px;
    background-color: var(--color-primary);
    margin-right: 10px;
}

.section-title .more {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
    transition: var(--transition);
}

.section-title .more:hover {
    color: var(--color-primary);
}

/* 卡片 */
.card {
    background-color: var(--color-white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-hover);
}

.card-header {
    padding: 15px 20px;
    border-bottom: 1px solid var(--color-border);
}

.card-body {
    padding: 20px;
}

.card-footer {
    padding: 15px 20px;
    border-top: 1px solid var(--color-border);
    background-color: var(--color-bg-alt);
}

/* 标签 */
.tag {
    display: inline-block;
    padding: 2px 10px;
    font-size: var(--font-size-sm);
    border-radius: 12px;
    background-color: var(--color-bg-section);
    color: var(--color-text-light);
}

.tag-primary {
    background-color: var(--color-primary);
    color: var(--color-white);
}

.tag-accent {
    background-color: var(--color-accent);
    color: var(--color-white);
}

/* 按钮 */
.btn {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    padding: 8px 20px;
    font-size: var(--font-size-base);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background-color: var(--color-white);
    color: var(--color-text);
    cursor: pointer;
    transition: var(--transition);
}

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

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

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

.btn-accent {
    background-color: var(--color-accent);
    border-color: var(--color-accent);
    color: var(--color-white);
}

.btn-accent:hover {
    background-color: #d35400;
    border-color: #d35400;
}

.btn-sm {
    padding: 5px 12px;
    font-size: var(--font-size-sm);
}

.btn-lg {
    padding: 12px 30px;
    font-size: var(--font-size-lg);
}

/* =========================================
   12. 回到顶部按钮
   ========================================= */
.back-to-top {
    position: fixed;
    right: 30px;
    bottom: 30px;
    width: 44px;
    height: 44px;
    background-color: var(--color-primary);
    color: var(--color-white);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: clamp(18px, 1.1vw + 6px, 24px);
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
    box-shadow: var(--shadow);
}

.back-to-top:hover {
    background-color: var(--color-primary-dark);
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

/* =========================================
   13. 列表样式
   ========================================= */
/* 新闻列表 */
.news-list li {
    padding: 12px 0;
    border-bottom: 1px dashed var(--color-border);
}

.news-list li:last-child {
    border-bottom: none;
}

.news-list a {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--color-text);
    transition: var(--transition);
}

.news-list a:hover {
    color: var(--color-primary);
}

.news-list .title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    padding-right: 20px;
}

.news-list .title::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 4px;
    background-color: var(--color-primary);
    border-radius: 50%;
    margin-right: 8px;
    vertical-align: middle;
}

.news-list .date {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    white-space: nowrap;
}

/* 图文列表 */
.media-list li {
    display: flex;
    gap: 15px;
    padding: 15px 0;
    border-bottom: 1px solid var(--color-border);
}

.media-list li:last-child {
    border-bottom: none;
}

.media-list .thumb {
    width: 120px;
    height: 80px;
    flex-shrink: 0;
    overflow: hidden;
    border-radius: var(--radius);
}

.media-list .thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.media-list .content {
    flex: 1;
    min-width: 0;
}

.media-list .content h4 {
    font-size: var(--font-size-base);
    font-weight: normal;
    margin-bottom: 8px;
}

.media-list .content h4 a {
    color: var(--color-text);
    transition: var(--transition);
}

.media-list .content h4 a:hover {
    color: var(--color-primary);
}

.media-list .content p {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
    line-height: 1.5;
    overflow: hidden;
    text-overflow: ellipsis;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

.media-list .meta {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    margin-top: 8px;
}

/* =========================================
   14. 图片列表/网格
   ========================================= */
.grid-list {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--gap);
}

.grid-item {
    background-color: var(--color-white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.grid-item:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
}

.grid-item .thumb {
    position: relative;
    padding-top: 66.67%; /* 3:2 比例 */
    overflow: hidden;
}

.grid-item .thumb img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.grid-item:hover .thumb img {
    transform: scale(1.05);
}

.grid-item .info {
    padding: 12px 15px;
}

.grid-item .info h4 {
    font-size: var(--font-size-base);
    font-weight: normal;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.grid-item .info h4 a {
    color: var(--color-text);
    transition: var(--transition);
}

.grid-item .info h4 a:hover {
    color: var(--color-primary);
}

/* =========================================
   15. 文章详情样式
   ========================================= */
.article-header {
    text-align: center;
    padding-bottom: 20px;
    margin-bottom: 25px;
    border-bottom: 1px solid var(--color-border);
}

.article-header h1 {
    font-size: var(--font-size-xxl);
    font-weight: bold;
    color: var(--color-text);
    line-height: 1.4;
    margin-bottom: 15px;
}

.article-header .meta {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
}

.article-header .meta span {
    margin: 0 10px;
}

.article-content {
    line-height: 1.8;
    font-size: var(--font-size-lg);
    color: var(--color-text);
}

.article-content p {
    margin-bottom: 1em;
    text-indent: 2em;
}

.article-content img {
    max-width: 100%;
    height: auto;
    margin: 15px auto;
    display: block;
}

.article-content h2,
.article-content h3,
.article-content h4 {
    margin: 1.5em 0 0.8em;
    font-weight: bold;
}

.article-content ul,
.article-content ol {
    margin: 1em 0;
    padding-left: 2em;
}

.article-content li {
    margin-bottom: 0.5em;
}

/* 文章底部 */
.article-footer {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--color-border);
}

.article-nav {
    display: flex;
    justify-content: space-between;
    font-size: var(--font-size-sm);
}

.article-nav a {
    color: var(--color-text-light);
    max-width: 45%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.article-nav a:hover {
    color: var(--color-primary);
}

/* =========================================
   16. 表单样式
   ========================================= */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-size: var(--font-size-base);
    color: var(--color-text);
}

.form-control {
    width: 100%;
    padding: 10px 15px;
    font-size: var(--font-size-base);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background-color: var(--color-white);
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(74, 124, 89, 0.1);
}

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

/* =========================================
   17. 其他辅助样式
   ========================================= */
/* 图片占位 */
.img-placeholder {
    background-color: var(--color-bg-section);
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--color-text-muted);
}

.empty-state .icon {
    font-size: clamp(40px, 2.5vw + 10px, 56px);
    margin-bottom: 15px;
    opacity: 0.5;
}

.empty-state .text {
    font-size: var(--font-size-lg);
}

/* 加载状态 */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px;
}

.loading::after {
    content: '';
    width: 30px;
    height: 30px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}