/* ============ 设计基调：纸白 / 黛青 / 铜金 —— 雅致简洁 ============ */
:root {
  --primary: #2F5753;
  --primary-dark: #233F3B;
  --primary-light: #E8EFEC;
  --accent: #A78A5E;
  --accent-light: #F3EDE2;
  --ink: #2B2B26;
  --text-2: #77766D;
  --border: #E6E3DB;
  --border-soft: #EFEDE6;
  --bg: #F8F7F3;
  --card: #FFFFFF;
  --radius: 4px;
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", "STSong", serif;
  --sans: "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--sans);
  font-size: 15px; line-height: 1.75; color: var(--ink); background: var(--bg);
}
a { color: var(--primary); text-decoration: none; transition: color .15s; }
a:hover { color: var(--accent); }
img { max-width: 100%; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }
main.container { padding-top: 28px; padding-bottom: 56px; }

/* ============ 顶部导航 ============ */
.site-header {
  background: rgba(255,255,255,.92); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-soft); position: sticky; top: 0; z-index: 100;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 66px; gap: 16px; }
.brand { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.brand-logo {
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--primary); color: #F5F1E8;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--serif); font-weight: 600; font-size: 15px; letter-spacing: .05em;
}
.brand-text { display: flex; flex-direction: column; line-height: 1.3; }
.brand-text strong { font-size: 16px; color: var(--ink); font-family: var(--serif); letter-spacing: .04em; }
.brand-text em { font-style: normal; font-size: 11px; color: var(--text-2); letter-spacing: .12em; }
.site-nav { display: flex; align-items: center; gap: 2px; flex-wrap: wrap; }
.site-nav > a {
  padding: 7px 11px; border-radius: 3px; font-size: 14px; color: var(--text-2); letter-spacing: .03em;
}
.site-nav > a:hover { background: var(--primary-light); color: var(--primary); }
.site-nav > a.active { color: var(--primary); font-weight: 600; background: var(--primary-light); }
.nav-user { display: flex; align-items: center; gap: 8px; margin-left: 8px; }
.user-name { font-size: 13px; color: var(--text-2); }
.inline-form { display: inline; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 1.5px; background: var(--ink); margin: 5px 0; transition: .2s; }

/* ============ 按钮 ============ */
.btn {
  display: inline-block; padding: 9px 22px; border-radius: 3px; border: 1px solid var(--primary);
  background: var(--primary); color: #F5F1E8; font-size: 14px; cursor: pointer;
  letter-spacing: .12em; transition: .15s;
}
.btn:hover { background: var(--primary-dark); border-color: var(--primary-dark); color: #FFF; }
.btn-outline { background: transparent; color: var(--primary); }
.btn-outline:hover { background: var(--primary-light); color: var(--primary-dark); }
.btn-outline-light { background: transparent; color: #F5F1E8; border-color: rgba(245,241,232,.5); }
.btn-outline-light:hover { background: rgba(245,241,232,.12); color: #FFF; border-color: #F5F1E8; }
.btn-ghost { background: transparent; border-color: var(--border); color: var(--text-2); }
.btn-ghost:hover { background: var(--bg); color: var(--ink); }
.btn-sm { padding: 5px 13px; font-size: 12.5px; letter-spacing: .06em; }
.btn-danger { border-color: #9A4B3C; background: #9A4B3C; }
.btn-danger:hover { background: #7E3B2F; border-color: #7E3B2F; }

/* ============ 提示条 ============ */
.flash { margin-top: 16px; padding: 10px 16px; border-radius: 3px; font-size: 14px; }
.flash-success { background: #EDF3E8; color: #4C6B33; }
.flash-error { background: #F9ECEA; color: #9A4B3C; }

/* ============ 页面标题 ============ */
.page-head { margin-bottom: 26px; padding-bottom: 14px; border-bottom: 1px solid var(--border-soft); }
.page-head h1 { font-size: 26px; font-family: var(--serif); letter-spacing: .1em; color: var(--ink); }
.page-head .sub { color: var(--text-2); font-size: 13.5px; margin-top: 6px; letter-spacing: .05em; }

/* ============ 首页 Hero ============ */
.hero {
  margin-top: 8px; padding: 54px 44px 46px;
  background: linear-gradient(180deg, #FFFFFF 0%, #FBFAF6 100%);
  border: 1px solid var(--border); border-top: 3px solid var(--accent);
  border-radius: var(--radius); text-align: center;
}
.hero-eyebrow { font-size: 12px; letter-spacing: .42em; color: var(--accent); margin-bottom: 14px; }
.hero h1 { font-family: var(--serif); font-size: 34px; letter-spacing: .14em; color: var(--ink); margin-bottom: 14px; font-weight: 600; }
.hero-lead { font-size: 15px; color: var(--text-2); max-width: 640px; margin: 0 auto; line-height: 1.9; }
.hero-actions { margin-top: 26px; display: flex; gap: 14px; justify-content: center; }

/* ============ 核心研究主题横幅 ============ */
.theme-band {
  margin-top: 22px; background: var(--primary-dark); border-radius: var(--radius);
  padding: 30px 36px; position: relative; overflow: hidden;
}
.theme-band::after {
  content: ''; position: absolute; right: -40px; top: -40px; width: 180px; height: 180px;
  border: 1px solid rgba(167,138,94,.35); border-radius: 50%;
}
.theme-band-inner { position: relative; }
.theme-label { font-size: 11px; letter-spacing: .5em; color: var(--accent); }
.theme-band h2 { font-family: var(--serif); font-size: 22px; letter-spacing: .06em; color: #F5F1E8; margin: 10px 0 8px; font-weight: 600; }
.theme-band p { font-size: 13.5px; color: rgba(245,241,232,.82); max-width: 720px; line-height: 1.9; }
.theme-link { display: inline-block; margin-top: 14px; font-size: 13px; letter-spacing: .1em; color: var(--accent); }
.theme-link:hover { color: #C9B48E; }

/* ============ 统计 ============ */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-top: 22px; }
.stat-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px 16px 18px; text-align: center;
}
.stat-card .num { font-size: 28px; font-weight: 400; font-family: var(--serif); color: var(--primary); letter-spacing: .04em; }
.stat-card .label { font-size: 12.5px; color: var(--text-2); margin-top: 4px; letter-spacing: .14em; }

/* ============ 首页网格 ============ */
.home-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 28px; margin-top: 34px; }
.home-col h2 {
  font-family: var(--serif); font-size: 16.5px; letter-spacing: .18em; color: var(--ink);
  margin-bottom: 16px; padding-bottom: 10px; position: relative; font-weight: 600;
}
.home-col h2::after { content: ''; position: absolute; left: 0; bottom: 0; width: 26px; height: 2px; background: var(--accent); }

/* ============ 卡片列表 ============ */
.card-list { display: flex; flex-direction: column; gap: 12px; }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px 20px; transition: border-color .15s, transform .15s; display: block;
}
.card:hover { border-color: var(--primary); transform: translateY(-1px); }
.card h3 { font-size: 15.5px; margin-bottom: 6px; color: var(--ink); }
.card h3 a { color: inherit; }
.card .meta { font-size: 12px; color: var(--text-2); display: flex; gap: 14px; flex-wrap: wrap; letter-spacing: .03em; }
.card .summary { font-size: 13.5px; color: var(--text-2); margin-top: 6px; line-height: 1.7; }
.tag {
  display: inline-block; font-size: 11px; padding: 1px 9px; border-radius: 2px;
  background: var(--primary-light); color: var(--primary); letter-spacing: .06em;
}

/* ============ 概况页 ============ */
.about-section {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px 32px; margin-bottom: 20px;
}
.about-section h2 {
  font-family: var(--serif); font-size: 18px; letter-spacing: .2em; color: var(--primary-dark);
  margin-bottom: 16px; padding-bottom: 10px; border-bottom: 1px solid var(--border-soft); font-weight: 600;
}
.about-intro { font-size: 15px; line-height: 2; text-align: justify; }
.mission-line { font-size: 14.5px; line-height: 2; padding-left: 4px; }
.structure-line { font-size: 14.5px; line-height: 2; padding-left: 4px; }
.timeline { list-style: none; border-left: 1px solid var(--border); padding-left: 26px; }
.timeline li { position: relative; margin-bottom: 18px; font-size: 14.5px; line-height: 1.8; color: var(--ink); }
.timeline li::before {
  content: ''; position: absolute; left: -31px; top: 8px; width: 9px; height: 9px;
  border-radius: 50%; background: var(--card); border: 2px solid var(--accent);
}
.timeline .year { font-family: var(--serif); font-weight: 600; color: var(--accent); margin-right: 10px; letter-spacing: .06em; }
.honor-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 12px; }
.honor-item {
  background: var(--bg); border: 1px solid var(--border-soft); border-radius: var(--radius);
  padding: 12px 16px; font-size: 13.5px; color: var(--ink); line-height: 1.7;
}

/* ============ 成员 ============ */
.member-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 18px; }
.member-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px 22px 22px; text-align: center; transition: border-color .15s;
}
.member-card:hover { border-color: var(--accent); }
.member-avatar {
  width: 62px; height: 62px; border-radius: 50%; margin: 0 auto 14px;
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--serif); font-size: 22px; border: 1px solid var(--border);
}
.member-card.is-host { border-color: var(--accent); border-width: 1px; }
.member-card.is-host .member-avatar { background: var(--accent-light); color: var(--accent); border-color: var(--accent); }
.member-card h3 { font-size: 16.5px; font-family: var(--serif); letter-spacing: .08em; color: var(--ink); }
.member-card .role { font-size: 12px; color: var(--accent); margin: 4px 0 3px; letter-spacing: .05em; }
.member-card .subject { font-size: 12px; color: var(--text-2); margin-bottom: 10px; }
.member-card .bio { font-size: 13px; color: var(--text-2); text-align: left; line-height: 1.8; }

/* ============ 文章详情 ============ */
.article-head { border-bottom: 1px solid var(--border-soft); padding-bottom: 16px; margin-bottom: 22px; }
.article-head h1 { font-size: 25px; font-family: var(--serif); line-height: 1.45; letter-spacing: .04em; color: var(--ink); }
.article-head .meta { font-size: 12.5px; color: var(--text-2); margin-top: 10px; display: flex; gap: 18px; flex-wrap: wrap; }
.article-body { font-size: 15px; white-space: pre-wrap; word-break: break-word; line-height: 2; }
.article-link { margin-top: 22px; padding: 14px 18px; background: var(--primary-light); border-radius: var(--radius); font-size: 14px; word-break: break-all; }
.detail-grid { display: grid; grid-template-columns: 1fr 260px; gap: 26px; }
.side-card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px 20px; }
.side-card h3 { font-size: 14.5px; font-family: var(--serif); letter-spacing: .12em; margin-bottom: 10px; color: var(--primary-dark); }
.side-card ul { list-style: none; }
.side-card li { padding: 7px 0; border-bottom: 1px dashed var(--border-soft); font-size: 13px; }
.side-card li:last-child { border-bottom: none; }

/* ============ 论坛 ============ */
.topic-item { display: flex; justify-content: space-between; gap: 14px; }
.reply-box { margin-top: 14px; }
.reply-list { margin-top: 26px; display: flex; flex-direction: column; gap: 12px; }
.reply-item { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 20px; }
.reply-item .who { font-size: 13px; color: var(--primary); font-weight: 600; }
.reply-item .when { font-size: 12px; color: var(--text-2); margin-left: 10px; }
.reply-item .content { margin-top: 8px; white-space: pre-wrap; word-break: break-word; font-size: 14px; line-height: 1.9; }
.badge-role { font-size: 11px; background: var(--primary-light); color: var(--primary); padding: 0 7px; border-radius: 2px; letter-spacing: .05em; }

/* ============ 表单 ============ */
.form-card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 30px; max-width: 560px; margin: 32px auto; }
.form-card.wide { max-width: 880px; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 13.5px; font-weight: 600; margin-bottom: 7px; color: var(--ink); letter-spacing: .05em; }
.form-control {
  width: 100%; padding: 9px 13px; border: 1px solid var(--border); border-radius: 3px;
  font-size: 14px; font-family: inherit; background: #fff; color: var(--ink); transition: border-color .15s;
}
.form-control:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-light); }
textarea.form-control { resize: vertical; min-height: 90px; line-height: 1.7; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-foot { font-size: 13px; color: var(--text-2); margin-top: 14px; }
.search-bar { display: flex; gap: 10px; margin-bottom: 20px; }
.search-bar .form-control { max-width: 320px; }

/* ============ 分页 ============ */
.pager { display: flex; gap: 8px; justify-content: center; margin-top: 30px; flex-wrap: wrap; }
.pager a, .pager span {
  padding: 6px 13px; border: 1px solid var(--border); border-radius: 3px; font-size: 13px;
  background: var(--card); color: var(--text-2);
}
.pager .cur { background: var(--primary); border-color: var(--primary); color: #F5F1E8; }

/* ============ 联系页 ============ */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.contact-info p { margin-bottom: 10px; font-size: 14px; }
.contact-info strong { color: var(--primary-dark); font-weight: 600; }

/* ============ 页脚 ============ */
.site-footer {
  border-top: 1px solid var(--border-soft); background: #FBF9F4;
  padding: 30px 0 40px; text-align: center; color: var(--text-2); font-size: 13px;
}
.site-footer p { margin-bottom: 5px; }
.site-footer .copyright { font-size: 12px; color: #A5A399; letter-spacing: .04em; }

/* ============ 移动端底部 Tab ============ */
.mobile-tabbar { display: none; }

/* ============ 后台 ============ */
.admin-wrap { display: grid; grid-template-columns: 208px 1fr; min-height: 100vh; }
.admin-side { background: #24332F; color: #C9D4CF; padding: 22px 0; }
.admin-side .side-brand { padding: 0 20px 20px; border-bottom: 1px solid rgba(255,255,255,.08); margin-bottom: 14px; }
.admin-side .side-brand strong { display: block; color: #F5F1E8; font-size: 15px; font-family: var(--serif); letter-spacing: .08em; }
.admin-side .side-brand em { font-style: normal; font-size: 11px; opacity: .55; letter-spacing: .12em; }
.admin-side a.side-link {
  display: block; padding: 10px 20px; color: #C9D4CF; font-size: 14px;
  border-left: 3px solid transparent; letter-spacing: .04em;
}
.admin-side a.side-link:hover { background: rgba(255,255,255,.06); color: #FFF; }
.admin-side a.side-link.active { background: rgba(47,87,83,.55); color: #FFF; border-left-color: var(--accent); }
.admin-side .side-group { font-size: 10.5px; opacity: .5; padding: 14px 20px 4px; text-transform: uppercase; letter-spacing: 2px; }
.admin-main { padding: 26px 30px; min-width: 0; background: var(--bg); }
.admin-main h1 { font-size: 21px; font-family: var(--serif); letter-spacing: .08em; margin-bottom: 18px; color: var(--ink); }
.admin-card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; margin-bottom: 20px; overflow-x: auto; }
.admin-card h3 { color: var(--primary-dark); }
.admin-stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 14px; margin-bottom: 24px; }
table.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th, .table td { padding: 11px 12px; border-bottom: 1px solid var(--border-soft); text-align: left; vertical-align: top; }
.table th { font-size: 11.5px; color: var(--text-2); text-transform: uppercase; letter-spacing: 1.5px; white-space: nowrap; font-weight: 600; }
.table tr:hover td { background: var(--bg); }
.table .ops { display: flex; gap: 6px; flex-wrap: wrap; }
.status-pill { display: inline-block; font-size: 12px; padding: 1px 10px; border-radius: 2px; letter-spacing: .04em; }
.status-published, .status-active, .status-approved { background: #EDF3E8; color: #4C6B33; }
.status-draft { background: #F7EFE0; color: #8A6424; }
.status-pending { background: var(--primary-light); color: var(--primary); }
.status-banned, .status-rejected { background: #F9ECEA; color: #9A4B3C; }
.admin-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 18px; flex-wrap: wrap; gap: 10px; }
.admin-top h1 { margin-bottom: 0; }
.admin-tabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 16px; }
.admin-tabs a { padding: 6px 15px; border-radius: 2px; font-size: 13px; background: var(--card); border: 1px solid var(--border); color: var(--text-2); letter-spacing: .05em; }
.admin-tabs a.active { background: var(--primary); border-color: var(--primary); color: #F5F1E8; }
.back-link { font-size: 13px; margin-bottom: 12px; display: inline-block; }

/* ============ 错误页 ============ */
.error-page { text-align: center; padding: 90px 20px; }
.error-page h1 { font-size: 64px; font-family: var(--serif); color: var(--border); }
.error-page p { color: var(--text-2); margin: 12px 0 26px; }

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  body { padding-bottom: 58px; } /* 给底部 tabbar 留空间 */
  .nav-toggle { display: block; }
  .site-nav {
    display: none; position: absolute; top: 66px; left: 0; right: 0;
    background: var(--card); border-bottom: 1px solid var(--border);
    flex-direction: column; align-items: stretch; padding: 10px 16px 16px; gap: 2px;
    max-height: 70vh; overflow-y: auto;
  }
  .site-nav.open { display: flex; }
  .site-nav > a { padding: 11px 12px; }
  .nav-user { margin: 8px 0 0; }
  .nav-toggle.open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
  .nav-toggle.open span:nth-child(2) { opacity: 0; }
  .nav-toggle.open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }
  .mobile-tabbar {
    display: grid; grid-template-columns: repeat(5, 1fr); position: fixed; bottom: 0; left: 0; right: 0;
    background: var(--card); border-top: 1px solid var(--border); z-index: 99; height: 56px;
  }
  .mobile-tabbar a { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 1px; color: var(--text-2); font-size: 11px; letter-spacing: .04em; }
  .mobile-tabbar a i { font-style: normal; font-size: 18px; line-height: 1; }
  .mobile-tabbar a.active { color: var(--primary); }
  .hero { padding: 36px 24px; }
  .hero h1 { font-size: 25px; }
  .hero-eyebrow { letter-spacing: .28em; }
  .theme-band { padding: 24px 22px; }
  .theme-band h2 { font-size: 18px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .home-grid { grid-template-columns: 1fr; }
  .detail-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .search-bar .form-control { max-width: none; }
  .about-section { padding: 22px 20px; }
  .admin-wrap { grid-template-columns: 1fr; }
  .admin-side { position: static; }
  .admin-side .side-links-scroll { display: flex; overflow-x: auto; padding: 8px 10px; gap: 2px; }
  .admin-side .side-link, .admin-side .side-group { white-space: nowrap; }
  .admin-side .side-group { display: none; }
  .admin-side a.side-link { border-left: none; border-bottom: 3px solid transparent; }
  .admin-side a.side-link.active { border-bottom-color: var(--accent); }
  .admin-main { padding: 16px; }
  .table th, .table td { padding: 8px 8px; font-size: 13px; }
  .mobile-hide { display: none; }
}

/* ============ 图片上传与展示 ============ */
.card.with-thumb { display: flex; gap: 16px; align-items: flex-start; }
.card-body { display: block; flex: 1; min-width: 0; }
.card-thumb { width: 108px; height: 76px; flex: 0 0 auto; object-fit: cover; border-radius: 6px; border: 1px solid var(--border); background: var(--primary-light); }
.article-cover { width: 100%; max-height: 420px; object-fit: cover; border-radius: 10px; border: 1px solid var(--border); margin-bottom: 22px; }
.member-avatar img { width: 100%; height: 100%; border-radius: 50%; object-fit: cover; }
.upload-box { border: 1px dashed var(--border); border-radius: var(--radius); padding: 14px; background: var(--paper); }
.upload-box input[type="file"] { font-size: 13px; color: var(--text-1); }
.upload-preview { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; flex-wrap: wrap; }
.upload-preview img { width: 150px; height: 96px; object-fit: cover; border-radius: 6px; border: 1px solid var(--border); background: var(--primary-light); }
.hint { font-size: 12px; color: var(--text-2); margin-top: 6px; line-height: 1.6; }
.admin-thumb { width: 56px; height: 40px; object-fit: cover; border-radius: 4px; border: 1px solid var(--border); display: block; background: var(--primary-light); }
.member-avatar-sm { width: 40px; height: 40px; border-radius: 50%; object-fit: cover; border: 1px solid var(--border); display: block; background: var(--primary-light); }
@media (max-width: 900px) {
  .card-thumb { width: 84px; height: 62px; }
}