/* ============================================================
   English Study — EyouCMS PC Template
   简洁 · 清爽 · 学习感
   ============================================================ */
:root {
  --brand: #0E8F86;
  --brand-deep: #0A6E67;
  --brand-soft: #E6F4F2;
  --accent: #F5A623;
  --ink: #1E2A32;
  --muted: #6B7A86;
  --bg: #F5F7F8;
  --card: #FFFFFF;
  --line: #E6EBEE;
  --radius: 12px;
  --shadow: 0 2px 10px rgba(30, 42, 50, .05);
  --shadow-hover: 0 6px 22px rgba(30, 42, 50, .09);
  --maxw: 1180px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; transition: color .15s ease; }
a:hover { color: var(--brand-deep); }
img { max-width: 100%; vertical-align: middle; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }
.clearfix::after { content: ""; display: block; clear: both; }
.muted { color: var(--muted); }

/* ============ 顶部导航 ============ */
.site-header {
  position: sticky; top: 0; z-index: 90;
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 22px;
  display: flex; align-items: center; justify-content: space-between; gap: 26px;
  height: 64px;
}
.logo { display: flex; align-items: center; gap: 10px; flex: 0 0 auto; }
.logo img { height: 34px; width: auto; display: block; }
.logo-name { font-size: 19px; font-weight: 700; color: var(--ink); letter-spacing: .3px; }
.logo-name em { font-style: normal; color: var(--brand); }
.nav-main { display: flex; align-items: center; gap: 4px; }
.nav-main > li { position: relative; list-style: none; }
.nav-main > li > a {
  display: block; padding: 8px 14px;
  color: var(--ink); font-size: 15px; font-weight: 500;
  border-radius: 8px;
}
.nav-main > li > a:hover { color: var(--brand); background: var(--brand-soft); }
.nav-main > li.active > a { color: var(--brand); font-weight: 700; }
.nav-main .drop {
  position: absolute; top: 100%; left: 0; min-width: 168px;
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  box-shadow: var(--shadow-hover);
  padding: 6px; display: none; z-index: 50;
}
.nav-main > li:hover .drop { display: block; }
.nav-main .drop a {
  display: block; padding: 8px 12px; font-size: 14px; color: var(--ink);
  border-radius: 7px;
}
.nav-main .drop a:hover { background: var(--brand-soft); color: var(--brand); }
.header-tools { display: flex; align-items: center; gap: 10px; flex: 0 0 auto; }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 50%;
  border: 1px solid var(--line); background: #fff; cursor: pointer;
  color: var(--ink); transition: all .15s ease;
}
.icon-btn:hover { border-color: var(--brand); color: var(--brand); background: var(--brand-soft); }
.icon-btn svg { width: 18px; height: 18px; }
.btn-login {
  font-size: 14px; color: var(--brand); font-weight: 600;
  padding: 7px 16px; border: 1px solid var(--brand); border-radius: 999px;
  background: #fff; transition: all .15s ease;
}
.btn-login:hover { background: var(--brand); color: #fff; }

/* 搜索弹出层 */
.search-pop {
  position: fixed; inset: 0; z-index: 200;
  background: rgba(20, 30, 38, .5);
  display: none; align-items: flex-start; justify-content: center;
  padding: 12vh 20px 0;
}
.search-pop.show { display: flex; }
.search-pop .box {
  width: 100%; max-width: 620px;
  background: #fff; border-radius: 14px;
  padding: 18px; box-shadow: 0 18px 50px rgba(0, 0, 0, .2);
}
.search-pop .form { display: flex; gap: 10px; }
.search-pop input {
  flex: 1; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px 16px; font-size: 15px; outline: none;
  transition: border-color .15s ease, box-shadow .15s ease;
}
.search-pop input:focus { border-color: var(--brand); box-shadow: 0 0 0 3px rgba(14,143,134,.12); }
.search-pop .go {
  border: none; background: var(--brand); color: #fff;
  padding: 0 26px; border-radius: 10px; font-size: 15px; cursor: pointer;
}
.search-pop .go:hover { background: var(--brand-deep); }
.search-pop .close { margin-top: 12px; text-align: right; }
.search-pop .close a { font-size: 13px; color: var(--muted); }

/* ============ Hero ============ */
.hero {
  background: linear-gradient(135deg, #0E8F86 0%, #159A8F 45%, #17A99C 100%);
  color: #fff; position: relative; overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; right: -120px; top: -120px;
  width: 420px; height: 420px; border-radius: 50%;
  background: rgba(255, 255, 255, .08);
}
.hero-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 84px 22px 96px;
  position: relative; z-index: 1; text-align: center;
}
.hero h1 {
  margin: 0 0 12px; font-size: 42px; font-weight: 800; letter-spacing: .5px;
  line-height: 1.25;
}
.hero p { margin: 0 auto 30px; font-size: 17px; opacity: .92; max-width: 560px; }
.hero-search {
  max-width: 560px; margin: 0 auto;
  display: flex; gap: 10px;
  background: #fff; border-radius: 999px; padding: 7px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, .15);
}
.hero-search input {
  flex: 1; border: none; outline: none; padding: 0 18px;
  font-size: 15px; background: transparent; color: var(--ink);
}
.hero-search button {
  border: none; background: var(--brand); color: #fff;
  padding: 11px 26px; border-radius: 999px; font-size: 15px; font-weight: 600;
  cursor: pointer; transition: background .15s ease;
}
.hero-search button:hover { background: var(--brand-deep); }
.hero-cats {
  margin-top: 30px; display: flex; justify-content: center;
  flex-wrap: wrap; gap: 10px;
}
.hero-cats a {
  color: #fff; font-size: 14px; padding: 7px 18px;
  border: 1px solid rgba(255, 255, 255, .45); border-radius: 999px;
  background: rgba(255, 255, 255, .1);
  transition: all .15s ease;
}
.hero-cats a:hover { background: #fff; color: var(--brand); }

/* ============ 区块 ============ */
.section { padding: 54px 0; }
.section.alt { background: #fff; }
.sec-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 26px;
}
.sec-head h2 { margin: 0; font-size: 24px; font-weight: 800; letter-spacing: .3px; }
.sec-head h2 small { color: var(--brand); font-size: 14px; font-weight: 700; margin-right: 10px; letter-spacing: 1px; }
.sec-head .more { font-size: 14px; color: var(--muted); }
.sec-head .more:hover { color: var(--brand); }

/* 文章卡片 */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
  transition: transform .18s ease, box-shadow .18s ease;
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); }
.card .thumb { display: block; aspect-ratio: 16 / 9; background: var(--brand-soft); overflow: hidden; }
.card .thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .3s ease; }
.card:hover .thumb img { transform: scale(1.04); }
.card .body { padding: 16px 18px 18px; display: flex; flex-direction: column; flex: 1; }
.card h3 { margin: 0 0 8px; font-size: 16px; font-weight: 700; line-height: 1.45; }
.card h3 a { color: var(--ink); }
.card h3 a:hover { color: var(--brand); }
.card p { margin: 0 0 14px; font-size: 13.5px; color: var(--muted); flex: 1; }
.card .meta { display: flex; align-items: center; gap: 12px; font-size: 12.5px; color: var(--muted); }
.card .meta .dot { width: 4px; height: 4px; border-radius: 50%; background: #C6D0D6; }

/* 数字热门列表 */
.hot-list { list-style: none; margin: 0; padding: 0; }
.hot-list li {
  display: flex; align-items: baseline; gap: 12px;
  padding: 13px 0; border-bottom: 1px dashed var(--line);
}
.hot-list li:last-child { border-bottom: none; }
.hot-list .no {
  flex: 0 0 26px; height: 26px; line-height: 26px; text-align: center;
  font-size: 13px; font-weight: 800; color: var(--muted);
  background: #EEF2F4; border-radius: 7px;
}
.hot-list li:nth-child(-n+3) .no { background: var(--brand); color: #fff; }
.hot-list a { color: var(--ink); font-size: 14.5px; flex: 1; }
.hot-list a:hover { color: var(--brand); }
.hot-list .cnt { font-size: 12px; color: #A8B4BC; white-space: nowrap; }

/* 栏目区块（首页栏目推荐） */
.cat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.cat-block {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px 20px 14px;
}
.cat-block h3 { margin: 0 0 4px; font-size: 17px; font-weight: 800; }
.cat-block h3 a { color: var(--ink); }
.cat-block h3 a:hover { color: var(--brand); }
.cat-block .en { font-size: 12.5px; color: var(--brand); letter-spacing: .5px; margin-bottom: 12px; }
.cat-block ul { list-style: none; margin: 0; padding: 0; }
.cat-block li { padding: 7px 0; border-bottom: 1px dashed var(--line); font-size: 14px; }
.cat-block li:last-child { border-bottom: none; }
.cat-block li a { color: var(--ink); }
.cat-block li a:hover { color: var(--brand); }
.cat-block li .d { float: right; font-size: 12px; color: #A8B4BC; }

/* 标语条 */
.banner-quote {
  background: var(--brand-soft); border-top: 1px solid #D3EAE6;
  border-bottom: 1px solid #D3EAE6; padding: 40px 0; text-align: center;
}
.banner-quote .en { font-size: 15px; color: var(--brand); letter-spacing: 1px; margin-bottom: 6px; }
.banner-quote h3 { margin: 0; font-size: 26px; font-weight: 800; }

/* ============ 面包屑 + 栏目头 ============ */
.breadcrumb { padding: 22px 0 6px; font-size: 13.5px; color: var(--muted); }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--brand); }
.breadcrumb .sep { margin: 0 8px; color: #C6D0D6; }
.page-head {
  padding: 44px 0 34px; text-align: center;
  background: linear-gradient(180deg, #EAF3F2 0%, var(--bg) 100%);
}
.page-head h1 { margin: 0 0 6px; font-size: 30px; font-weight: 800; }
.page-head .en { color: var(--brand); font-size: 15px; letter-spacing: 1px; }

/* 子栏目 tab */
.cat-tabs { display: flex; flex-wrap: wrap; gap: 10px; margin: 22px 0; }
.cat-tabs a {
  padding: 7px 18px; border-radius: 999px;
  border: 1px solid var(--line); background: #fff;
  color: var(--ink); font-size: 14px;
}
.cat-tabs a:hover { border-color: var(--brand); color: var(--brand); }
.cat-tabs a.active { background: var(--brand); border-color: var(--brand); color: #fff; font-weight: 600; }

/* ============ 列表 ============ */
.list-items { display: grid; gap: 18px; }
.list-item {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px;
  display: flex; gap: 20px;
  transition: box-shadow .15s ease;
}
.list-item:hover { box-shadow: var(--shadow-hover); }
.list-item .thumb {
  flex: 0 0 210px; height: 132px; border-radius: 10px; overflow: hidden; background: var(--brand-soft);
}
.list-item .thumb img { width: 100%; height: 100%; object-fit: cover; }
.list-item .info { flex: 1; display: flex; flex-direction: column; }
.list-item h3 { margin: 0 0 8px; font-size: 18px; font-weight: 700; line-height: 1.4; }
.list-item h3 a { color: var(--ink); }
.list-item h3 a:hover { color: var(--brand); }
.list-item p { margin: 0 0 12px; font-size: 13.5px; color: var(--muted); flex: 1; }
.list-item .meta { display: flex; align-items: center; gap: 14px; font-size: 12.5px; color: var(--muted); }
.list-item .meta .tag {
  background: var(--brand-soft); color: var(--brand);
  padding: 2px 10px; border-radius: 999px; font-size: 12px;
}

/* 分页 */
.pagination { display: flex; justify-content: center; align-items: center; gap: 6px; margin: 34px 0 0; list-style: none; padding: 0; flex-wrap: wrap; }
.pagination li a, .pagination li span {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 36px; height: 36px; padding: 0 12px;
  border: 1px solid var(--line); border-radius: 9px;
  background: #fff; color: var(--ink); font-size: 14px;
}
.pagination li a:hover { border-color: var(--brand); color: var(--brand); }
.pagination li.thisclass span, .pagination li.active span, .pagination li.thisclass a {
  background: var(--brand); border-color: var(--brand); color: #fff; font-weight: 700;
}

/* ============ 详情页（单栏，无侧栏） ============ */
.detail-wrap { display: block; max-width: 860px; margin: 0 auto; padding: 20px 0 60px; }
.detail-main {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 30px 34px;
}
.detail-main h1 { margin: 0 0 14px; font-size: 26px; font-weight: 800; line-height: 1.4; }
.detail-meta {
  display: flex; flex-wrap: wrap; gap: 16px;
  font-size: 13px; color: var(--muted);
  padding-bottom: 18px; border-bottom: 1px solid var(--line); margin-bottom: 22px;
}
.detail-content { font-size: 15.5px; line-height: 1.9; color: #26323B; }
.detail-content p { margin: 0 0 18px; }
.detail-content img { border-radius: 10px; margin: 10px 0; }
.detail-content h2, .detail-content h3 { margin: 26px 0 12px; }
.detail-content a { color: var(--brand); text-decoration: underline; }
.detail-nav {
  display: flex; justify-content: space-between; gap: 20px;
  margin-top: 30px; padding-top: 18px; border-top: 1px solid var(--line);
  font-size: 14px;
}
.detail-nav .prev, .detail-nav .next { max-width: 48%; }
.detail-nav .lab { color: var(--muted); margin-right: 6px; }
.detail-nav a { color: var(--ink); }
.detail-nav a:hover { color: var(--brand); }
.side {
  display: grid; gap: 20px; position: sticky; top: 84px;
}
.side .panel {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px;
}
.side h3 { margin: 0 0 4px; font-size: 16px; font-weight: 800; }
.side .en { font-size: 12px; color: var(--brand); letter-spacing: .5px; margin-bottom: 12px; }
.side .list { list-style: none; margin: 0; padding: 0; }
.side .list li { padding: 8px 0; border-bottom: 1px dashed var(--line); font-size: 14px; }
.side .list li:last-child { border-bottom: none; }
.side .list a { color: var(--ink); }
.side .list a:hover { color: var(--brand); }
.side .list .d { float: right; font-size: 12px; color: #A8B4BC; }

/* ============ 单页 ============ */
.single-page {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 34px; margin: 10px 0 60px;
}
.single-page .content { font-size: 15.5px; line-height: 1.9; color: #26323B; }
.single-page .content p { margin: 0 0 18px; }
.single-page .content img { border-radius: 10px; }

/* ============ 页脚 ============ */
.site-footer { background: #17262E; color: #A9B8C0; margin-top: 10px; }
.footer-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 46px 22px 26px;
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 34px;
}
.footer-inner h4 { color: #fff; font-size: 15px; margin: 0 0 14px; font-weight: 700; }
.footer-inner p { font-size: 13.5px; margin: 0 0 8px; line-height: 1.8; }
.footer-inner ul { list-style: none; margin: 0; padding: 0; }
.footer-inner li { margin-bottom: 9px; }
.footer-inner a { color: #A9B8C0; font-size: 13.5px; }
.footer-inner a:hover { color: #fff; }
.footer-brand { font-size: 22px; font-weight: 800; color: #fff; margin-bottom: 10px; }
.footer-brand em { font-style: normal; color: #3FBFB4; }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, .08);
  text-align: center; padding: 18px 22px;
  font-size: 12.5px; color: #7C8C95;
}
.footer-bottom a { color: #7C8C95; }
.footer-bottom a:hover { color: #fff; }

/* 回到顶部 */
.to-top {
  position: fixed; right: 26px; bottom: 30px; z-index: 80;
  width: 42px; height: 42px; border-radius: 50%;
  background: var(--brand); color: #fff; border: none; cursor: pointer;
  display: none; align-items: center; justify-content: center;
  box-shadow: 0 6px 18px rgba(14, 143, 134, .35);
}
.to-top.show { display: inline-flex; }
.to-top:hover { background: var(--brand-deep); }
.to-top svg { width: 18px; height: 18px; }

/* ============ 响应式 ============ */
@media (max-width: 980px) {
  .cards, .cat-grid { grid-template-columns: repeat(2, 1fr); }
  .detail-wrap { grid-template-columns: 1fr; }
  .side { position: static; grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 760px) {
  .header-inner { height: 58px; }
  .nav-main { display: none; }
  .js-nav-toggle { display: inline-flex !important; }
  .nav-main.open {
    display: flex; flex-direction: column; gap: 2px;
    position: absolute; top: 58px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    padding: 10px 22px 16px; box-shadow: var(--shadow);
  }
  .nav-main.open > li > a { padding: 11px 12px; font-size: 16px; }
  .nav-main.open .drop {
    position: static; display: block; box-shadow: none;
    border: none; border-left: 2px solid var(--brand-soft);
    border-radius: 0; margin: 2px 0 6px 14px; padding: 2px 0 2px 6px; min-width: 0;
  }
  .hero h1 { font-size: 30px; }
  .cards, .cat-grid { grid-template-columns: 1fr; }
  .list-item { flex-direction: column; }
  .list-item .thumb { flex: none; width: 100%; height: 170px; }
  .detail-main { padding: 20px; }
  .side { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; gap: 22px; }
  .section { padding: 38px 0; }
}