/* ========== ICN Group — 2026 ========== */
:root {
  --navy: #0b1f3a;
  --navy-2: #13325c;
  --blue: #1d4ed8;
  --teal: #14b8a6;
  --ink: #1b2430;
  --muted: #5d6b7c;
  --line: #e4e9f0;
  --bg: #ffffff;
  --bg-alt: #f5f7fb;
  --max: 1200px;
  --head: "Space Grotesk", "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body { margin: 0; font-family: var(--body); font-size: 17px; line-height: 1.7; color: var(--ink); background: var(--bg); -webkit-font-smoothing: antialiased; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 28px; }

/* ---------- 顶部导航 ---------- */
.site-header { position: sticky; top: 0; z-index: 20; background: rgba(255,255,255,.95); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--ink); }
.brand:hover { text-decoration: none; }
.brand-mark { width: 40px; height: 40px; border-radius: 10px; background: linear-gradient(135deg, var(--navy-2), var(--blue)); color: #fff; display: grid; place-items: center; font-family: var(--head); font-weight: 700; font-size: 15px; letter-spacing: .04em; }
.brand-text b { display: block; font-family: var(--head); font-size: 18px; line-height: 1.1; }
.brand-text span { font-size: 12.5px; color: var(--muted); letter-spacing: .02em; }
.site-nav { display: flex; gap: 4px; }
.site-nav a { color: var(--muted); font-weight: 500; font-size: 15.5px; padding: 8px 14px; border-radius: 8px; }
.site-nav a:hover { color: var(--ink); background: var(--bg-alt); text-decoration: none; }
.site-nav a.active { color: var(--blue); background: #eef3ff; }

/* ---------- 首页大标题区 ---------- */
.hero {
  position: relative; overflow: hidden; color: #fff;
  background: radial-gradient(1200px 500px at 85% 20%, rgba(20,184,166,.22), transparent 60%),
              linear-gradient(135deg, var(--navy) 0%, var(--navy-2) 100%);
}
.hero svg.net { position: absolute; right: -40px; top: 0; height: 100%; width: 55%; opacity: .35; }
.hero .wrap { position: relative; padding-top: 84px; padding-bottom: 84px; }
.hero .eyebrow { font-size: 13px; letter-spacing: .22em; text-transform: uppercase; color: #7dd3c7; margin: 0 0 14px; }
.hero h1 { font-family: var(--head); font-size: 54px; line-height: 1.08; margin: 0 0 18px; max-width: 760px; }
.hero p.lead { font-size: 19px; color: #cdd8ea; max-width: 680px; margin: 0 0 30px; }
.hero .cta { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-block; font-weight: 600; font-size: 15px; padding: 10px 20px; border-radius: 10px; border: 1px solid transparent; }
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--teal); color: #052e2b; }
.btn-primary:hover { background: #2dd4bf; }
.btn-ghost { border-color: rgba(255,255,255,.35); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.08); }

/* 合作机构条 */
.partners { background: var(--bg-alt); border-bottom: 1px solid var(--line); }
.partners .wrap { display: flex; align-items: center; justify-content: center; gap: 28px; padding-top: 18px; padding-bottom: 18px; flex-wrap: wrap; }
.partners span { font-size: 13px; letter-spacing: .16em; text-transform: uppercase; color: var(--muted); }
.partners img { height: 64px; width: auto; }

/* ---------- 通用区块 ---------- */
section.block { padding: 64px 0 8px; }
.block .kicker { font-size: 13px; font-weight: 600; letter-spacing: .18em; text-transform: uppercase; color: var(--teal); margin: 0 0 8px; }
.block h2 { font-family: var(--head); font-size: 34px; line-height: 1.2; margin: 0 0 22px; }
.block .intro { max-width: 860px; color: #334155; }
.block .intro p { margin: 0 0 16px; }

/* 研究方向卡片 */
.areas { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 8px; }
.area { border: 1px solid var(--line); border-radius: 14px; padding: 22px 22px 20px; background: #fff; transition: box-shadow .2s, border-color .2s, transform .2s; }
.area:hover { border-color: #c9d6ee; box-shadow: 0 12px 28px rgba(11,31,58,.08); transform: translateY(-2px); }
.area .ic { width: 42px; height: 42px; border-radius: 10px; background: #eef3ff; color: var(--blue); display: grid; place-items: center; margin-bottom: 14px; }
.area .ic svg { width: 22px; height: 22px; }
.area h3 { font-family: var(--head); font-size: 19px; margin: 0 0 6px; }
.area p { margin: 0; font-size: 15px; color: var(--muted); line-height: 1.55; }

/* 项目列表 */
.projects { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 14px 28px; }
.projects li { border-left: 3px solid var(--teal); padding: 6px 0 6px 16px; }
.projects b { display: block; font-weight: 600; line-height: 1.45; }
.projects span { font-size: 14.5px; color: var(--muted); }

/* ---------- 子页面标题 ---------- */
.page-head { background: linear-gradient(135deg, var(--navy) 0%, var(--navy-2) 100%); color: #fff; }
.page-head .wrap { padding-top: 48px; padding-bottom: 44px; }
.page-head h1 { font-family: var(--head); font-size: 42px; margin: 0 0 6px; }
.page-head p { margin: 0; color: #cdd8ea; }

/* 论文 */
.pubs { list-style: none; padding: 0; margin: 0; counter-reset: p; }
.pubs li { counter-increment: p; display: grid; grid-template-columns: 54px 1fr; gap: 6px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.pubs li::before { content: counter(p, decimal-leading-zero); font-family: var(--head); color: #b6c2d3; font-size: 20px; }
.pubs .venue { display: inline-block; font-size: 11.5px; font-weight: 700; letter-spacing: .06em; color: var(--blue); background: #eef3ff; padding: 2px 9px; border-radius: 6px; margin-right: 8px; vertical-align: 2px; }
.pubs .title { font-weight: 600; font-size: 17.5px; line-height: 1.45; }
.pubs .authors { font-size: 15px; color: #334155; margin-top: 2px; }
.pubs .where { font-size: 14.5px; color: var(--muted); font-style: italic; }

/* 团队 */
.people { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.person { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 24px 16px 20px; text-align: center; transition: box-shadow .2s, transform .2s; }
.person:hover { box-shadow: 0 12px 28px rgba(11,31,58,.08); transform: translateY(-2px); }
.person img { width: 120px; height: 120px; border-radius: 50%; object-fit: cover; border: 4px solid #fff; box-shadow: 0 0 0 2px var(--teal), 0 8px 18px rgba(11,31,58,.12); margin-bottom: 14px; }
.person h3 { font-family: var(--head); font-size: 18px; margin: 0 0 4px; line-height: 1.3; }
.person .role { color: var(--blue); font-weight: 600; font-size: 14.5px; }
.person .org { color: var(--muted); font-size: 14px; }
.person .badge { display: inline-block; margin-top: 8px; font-size: 12px; font-weight: 600; color: #0f766e; background: #e6fbf8; padding: 2px 10px; border-radius: 999px; }
.team-sec + .team-sec { border-top: 1px solid var(--line); margin-top: 48px; }

/* ---------- 页脚 ---------- */
.site-footer { margin-top: 80px; background: var(--navy); color: #b9c6da; font-size: 14.5px; }
.site-footer .wrap { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 32px; padding-top: 44px; padding-bottom: 40px; }
.site-footer h4 { color: #fff; font-family: var(--head); font-size: 16px; margin: 0 0 10px; }
.site-footer p { margin: 0 0 6px; }
.site-footer a { color: #fff; }
.site-footer .copy { grid-column: 1 / -1; border-top: 1px solid rgba(255,255,255,.12); padding-top: 18px; font-size: 13px; color: #8b9ab3; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .areas { grid-template-columns: 1fr 1fr; }
  .people { grid-template-columns: repeat(3, 1fr); }
  .projects { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .site-header { position: static; }
  .site-header .wrap { height: auto; flex-direction: column; align-items: flex-start; gap: 8px; padding-top: 12px; padding-bottom: 10px; }
  .site-nav { margin-left: -14px; }
  .hero .wrap { padding-top: 56px; padding-bottom: 56px; }
  .hero h1 { font-size: 36px; }
  .hero svg.net { width: 100%; opacity: .15; }
  .areas { grid-template-columns: 1fr; }
  .people { grid-template-columns: 1fr 1fr; gap: 12px; }
  .person img { width: 96px; height: 96px; }
  .pubs li { grid-template-columns: 1fr; }
  .pubs li::before { font-size: 15px; }
  .site-footer .wrap { grid-template-columns: 1fr; }
  .partners img { height: 48px; }
}
.partners img { height: 84px; } .partners .wrap { padding-top: 22px; padding-bottom: 22px; }
/* 没有照片时的姓名首字母头像 */
.person .avatar { width: 120px; height: 120px; border-radius: 50%; margin: 0 auto 14px; display: grid; place-items: center; font-family: var(--head); font-size: 34px; font-weight: 700; color: #fff; background: linear-gradient(135deg, var(--navy-2), var(--blue)); border: 4px solid #fff; box-shadow: 0 0 0 2px var(--teal), 0 8px 18px rgba(11,31,58,.12); }
@media (max-width: 720px) { .person .avatar { width: 96px; height: 96px; font-size: 28px; } }