/* 天宸科技官网 v2 - 浅色极简工程风 */
:root {
  --ink: #1A1D23;
  --ink-2: #5B6169;
  --bg: #FFFFFF;
  --bg-2: #F4F5F6;
  --accent: #E0651F;
  --accent-dark: #B94E14;
  --dark: #15181D;
  --line: #E3E5E8;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink); background: var(--bg); line-height: 1.75; font-size: 15px;
}
a { color: var(--ink); text-decoration: none; }
a:hover { color: var(--accent); }

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }

/* ===== 顶部工具条 ===== */
.topbar { background: var(--dark); color: #AEB4BC; font-size: 12.5px; }
.topbar .container { display: flex; justify-content: space-between; align-items: center; height: 36px; }
.topbar a { color: #AEB4BC; }
.topbar a:hover { color: #fff; }
.topbar .tb-right { display: flex; gap: 22px; }

/* ===== 导航 ===== */
.nav { position: sticky; top: 0; z-index: 100; background: #fff; border-bottom: 1px solid var(--line); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 74px; }
.brand { display: flex; align-items: center; gap: 12px; min-width: 0; flex-shrink: 1; }
.brand-logo { height: 34px; width: auto; display: block; flex-shrink: 0; }
.brand-text { font-size: 17px; font-weight: 800; line-height: 1.3; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.brand-text small { display: block; font-size: 10.5px; font-weight: 400; color: var(--ink-2); letter-spacing: .6px; }

.nav-menu { display: flex; align-items: center; gap: 2px; }
.nav-menu > a { font-size: 15px; padding: 8px 15px; position: relative; }
.nav-menu > a:hover { color: var(--accent); }
.nav-menu > a.active { color: var(--accent); font-weight: 700; }
.nav-menu > a.active::after {
  content: ""; position: absolute; left: 15px; right: 15px; bottom: 0; height: 2px; background: var(--accent);
}
.btn {
  display: inline-block; padding: 10px 26px; font-size: 15px; cursor: pointer;
  border: none; text-align: center; transition: all .2s; font-weight: 600;
}
.btn-quote { background: var(--accent); color: #fff !important; margin-left: 12px; }
.btn-quote:hover { background: var(--accent-dark); }
.btn-dark { background: var(--dark); color: #fff; }
.btn-dark:hover { background: #000; }
.btn-white { background: #fff; color: var(--accent-dark); }
.btn-white:hover { background: var(--bg-2); }

.nav-toggle { display: none; background: none; border: none; font-size: 24px; color: var(--ink); cursor: pointer; padding: 6px; }

/* ===== 首页 Hero（非轮播，排版式） ===== */
.hero { padding: 78px 0 70px; border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 56px; align-items: center; }
.hero-kicker {
  display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 3px;
  color: var(--accent); margin-bottom: 20px;
}
.hero-kicker::before { content: ""; display: inline-block; width: 30px; height: 2px; background: var(--accent); vertical-align: middle; margin-right: 10px; }
.hero-title { font-size: 46px; font-weight: 800; line-height: 1.3; letter-spacing: -1px; margin-bottom: 20px; }
.hero-title em { font-style: normal; color: var(--accent); }
.hero-sub { font-size: 16.5px; color: var(--ink-2); max-width: 560px; margin-bottom: 34px; }
.hero-actions { display: flex; gap: 14px; }
.hero-panel { background: var(--dark); color: #fff; padding: 34px 32px; }
.hero-panel h3 { font-size: 15px; font-weight: 700; color: var(--accent); letter-spacing: 2px; margin-bottom: 18px; }
.hp-row { display: flex; justify-content: space-between; padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,.12); font-size: 13.5px; }
.hp-row:last-child { border-bottom: none; }
.hp-row b { font-size: 15px; font-weight: 700; }
.hp-row span { color: #AEB4BC; }

/* ===== 数据条（深色，吸收 v1 优点） ===== */
.stats { background: var(--dark); }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { padding: 34px 10px 34px 26px; border-right: 1px solid rgba(255,255,255,.1); }
.stat:last-child { border-right: none; }
.stat b { display: block; font-size: 34px; font-weight: 800; color: #fff; }
.stat b em { font-style: normal; font-size: 15px; font-weight: 600; color: rgba(255,255,255,.55); margin-left: 4px; }
.stat span { font-size: 13px; color: rgba(255,255,255,.6); }

/* ===== 通用区块 ===== */
.section { padding: 72px 0; }
.section.alt { background: var(--bg-2); }
.sec-head { display: flex; align-items: baseline; gap: 20px; margin-bottom: 40px; }
.sec-num { font-size: 15px; font-weight: 800; color: var(--accent); letter-spacing: 2px; }
.sec-head h2 { font-size: 30px; font-weight: 800; letter-spacing: -0.5px; }
.sec-head p { color: var(--ink-2); margin-left: auto; font-size: 14.5px; }

/* ===== 产品线行式列表 ===== */
.plist { border-top: 2px solid var(--ink); }
.pitem { display: grid; grid-template-columns: 60px 1.1fr 2fr auto; gap: 26px; align-items: center; padding: 24px 10px; border-bottom: 1px solid var(--line); transition: background .2s; }
.pitem:hover { background: var(--bg-2); }
.pitem .idx { font-size: 20px; font-weight: 800; color: var(--accent); }
.pitem h3 { font-size: 18px; font-weight: 800; }
.pitem h3 small { display: block; font-size: 11px; font-weight: 500; color: var(--ink-2); letter-spacing: 1.5px; margin-top: 2px; }
.pitem p { font-size: 14px; color: var(--ink-2); }
.pitem .go { font-size: 14px; font-weight: 700; color: var(--accent); white-space: nowrap; }

/* ===== 标准入口（深色块） ===== */
.std-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.std-item { background: var(--dark); color: #fff; padding: 30px 28px; transition: transform .2s; }
.std-item:hover { transform: translateY(-4px); }
.std-item .tag { font-size: 12px; font-weight: 700; color: var(--accent); letter-spacing: 2px; }
.std-item h3 { font-size: 20px; font-weight: 800; margin: 12px 0 10px; }
.std-item p { font-size: 13.5px; color: #AEB4BC; margin-bottom: 18px; }
.std-item .go { color: var(--accent); font-weight: 700; font-size: 14px; }

/* ===== 优势 ===== */
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 26px; }
.adv { border-left: 3px solid var(--accent); padding: 6px 0 6px 20px; }
.adv h3 { font-size: 17px; font-weight: 800; margin-bottom: 10px; }
.adv p { font-size: 13.5px; color: var(--ink-2); }

/* ===== CTA ===== */
.cta { background: var(--accent); color: #fff; padding: 60px 0; }
.cta .container { display: flex; align-items: center; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.cta h2 { font-size: 26px; font-weight: 800; }
.cta p { opacity: .92; margin-top: 6px; }

/* ===== 页脚 ===== */
.footer { background: var(--dark); color: #AEB4BC; padding: 56px 0 0; font-size: 13.5px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1.4fr; gap: 44px; padding-bottom: 40px; }
.footer h4 { color: #fff; font-size: 15px; margin-bottom: 18px; font-weight: 800; }
.footer p { margin-bottom: 7px; }
.footer a { color: #AEB4BC; }
.footer a:hover { color: #fff; }
.footer-links a { display: block; margin-bottom: 10px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); padding: 18px 0; text-align: center; font-size: 12.5px; color: #7E8590; }

/* ===== 内页头 ===== */
.phead { padding: 52px 0 40px; border-bottom: 1px solid var(--line); background: var(--bg-2); }
.phead .crumb { font-size: 12.5px; color: var(--ink-2); margin-bottom: 14px; }
.phead h1 { font-size: 34px; font-weight: 800; letter-spacing: -0.5px; }
.phead h1::after { content: ""; display: block; width: 52px; height: 4px; background: var(--accent); margin-top: 14px; }

/* ===== 内页产品区 ===== */
.psec { padding: 56px 0 34px; border-bottom: 1px solid var(--line); }
.psec:last-of-type { border-bottom: none; }
.psec-head { display: flex; align-items: baseline; gap: 16px; margin-bottom: 18px; }
.psec-head .no { font-size: 14px; font-weight: 800; color: var(--accent); letter-spacing: 2px; }
.psec-head h2 { font-size: 23px; font-weight: 800; }
.psec-head .en { font-size: 12px; color: var(--ink-2); letter-spacing: 1.5px; }
.psec-intro { color: var(--ink-2); max-width: 900px; margin-bottom: 24px; }

.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 22px; }
.chip { border: 1px solid var(--line); padding: 4px 15px; font-size: 13px; font-weight: 600; color: var(--ink-2); }
a.chip:hover { border-color: var(--accent); color: var(--accent); }

.spec-wrap { overflow-x: auto; }
.spec-table { width: 100%; border-collapse: collapse; font-size: 13.5px; min-width: 640px; }
.spec-table th, .spec-table td { border: 1px solid var(--line); padding: 10px 13px; text-align: left; }
.spec-table thead th { background: var(--dark); color: #fff; font-weight: 600; white-space: nowrap; }
.spec-table tbody tr:nth-child(even) { background: var(--bg-2); }
.spec-table td:first-child { font-weight: 700; white-space: nowrap; }
.note { font-size: 12.5px; color: var(--ink-2); margin-top: 12px; }
h3.sub { font-size: 17px; font-weight: 800; margin: 0 0 16px; padding-left: 12px; border-left: 4px solid var(--accent); }

/* ===== 联系页 ===== */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-bottom: 46px; }
.contact-card { border: 1px solid var(--line); padding: 26px 24px; }
.contact-card h3 { font-size: 12.5px; font-weight: 700; color: var(--accent); letter-spacing: 2px; margin-bottom: 12px; }
.contact-card p { font-size: 14.5px; margin-bottom: 6px; }
.contact-card b { font-size: 17px; font-weight: 800; }

.form-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.form-item { display: flex; flex-direction: column; gap: 6px; }
.form-item.full { grid-column: 1 / -1; }
.form-item label { font-size: 14px; font-weight: 700; }
.form-item label i { color: var(--accent); font-style: normal; }
.form-item input, .form-item select, .form-item textarea {
  border: 1px solid var(--line); padding: 11px 13px; font-size: 14px; font-family: inherit;
  background: #fff; transition: border .2s;
}
.form-item input:focus, .form-item select:focus, .form-item textarea:focus { outline: none; border-color: var(--accent); }
.form-ok { display: none; background: #FFF3EA; border: 1px solid #F3CBA9; color: var(--accent-dark); padding: 12px 16px; margin-top: 14px; font-size: 14px; }
.form-ok.error { background: #FDECEA; border-color: #E6B0AA; color: #8C1D18; }

/* ===== 下载页 ===== */
.dl-list { border-top: 2px solid var(--ink); }
.dl-item { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 18px 10px; border-bottom: 1px solid var(--line); }
.dl-item .name { font-weight: 800; font-size: 15.5px; }
.dl-item .desc { font-size: 13px; color: var(--ink-2); margin-top: 2px; }
.dl-item .tag { font-size: 12.5px; color: var(--accent-dark); background: #FFF3EA; border: 1px solid #F3CBA9; padding: 4px 14px; white-space: nowrap; }
.dl-item .meta { font-size: 12.5px; color: #8A9099; margin-top: 4px; }
.dl-item .dl-btn { font-size: 13px; font-weight: 700; color: var(--ink); border: 1px solid var(--ink); padding: 7px 18px; white-space: nowrap; transition: all .18s; display: inline-block; }
.dl-item .dl-btn:hover { background: var(--ink); color: #fff; }
.dl-item .dl-btn::after { content: " ↓"; }

/* ===== 产品照片 ===== */
.photo-band { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 44px; }
.photo-band figure { border: 1px solid var(--line); border-radius: 8px; overflow: hidden; background: #fff; }
.photo-band img { width: 100%; height: 200px; object-fit: contain; padding: 12px; display: block; }
.photo-band figcaption { padding: 8px 14px 12px; font-size: 13px; color: var(--ink-2); border-top: 1px solid var(--line); }

.psec-photos { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin: 22px 0 26px; }
.psec-photos.three { grid-template-columns: repeat(3, 1fr); }
.psec-photos.two { grid-template-columns: repeat(2, 1fr); max-width: 760px; }
.psec-photos.one { grid-template-columns: 1fr; max-width: 520px; }
.psec-photos figure { border: 1px solid var(--line); border-radius: 8px; overflow: hidden; background: #fff; }
.psec-photos img { width: 100%; height: 200px; object-fit: contain; padding: 12px; display: block; }
.psec-photos figcaption { padding: 8px 14px 12px; font-size: 13px; color: var(--ink-2); border-top: 1px solid var(--line); }

.about-photo { margin-top: 34px; max-width: 620px; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; background: #fff; }
.about-photo img { width: 100%; display: block; }
.about-photo figcaption { padding: 10px 16px; font-size: 13px; color: var(--ink-2); border-top: 1px solid var(--line); }

/* ===== 响应式 ===== */
@media (max-width: 960px) {
  /* 顶栏：只留电话，避免截断 */
  .topbar .container > span:first-child,
  .topbar .tb-right span:last-child { display: none; }
  .topbar .container { justify-content: center; }
  /* 导航提前折叠为汉堡菜单，避免竖排拥挤 */
  .nav-toggle { display: block; }
  .nav-menu {
    display: none; position: absolute; top: 74px; left: 0; right: 0; background: #fff;
    flex-direction: column; align-items: stretch; padding: 10px 24px 18px;
    border-bottom: 1px solid var(--line); box-shadow: 0 12px 20px rgba(0,0,0,.1);
  }
  .nav-menu.open { display: flex; }
  .nav-menu > a { padding: 12px 4px; }
  .btn-quote { margin: 8px 0 0; margin-left: 0; text-align: center; }
  .brand-text { font-size: 15px; }

  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero-title { font-size: 32px; }
  .adv-grid, .std-grid, .contact-grid { grid-template-columns: repeat(2, 1fr); }
  .photo-band { grid-template-columns: repeat(2, 1fr); }
  .psec-photos, .psec-photos.three { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat { border-right: none; border-bottom: 1px solid rgba(255,255,255,.1); padding-left: 10px; }
  .pitem { grid-template-columns: 40px 1fr; grid-template-rows: auto auto; }
  .pitem p, .pitem .go { grid-column: 2; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
}
@media (max-width: 640px) {
  .brand-text { font-size: 13.5px; }
  .brand-text small { letter-spacing: .3px; }
  .brand-logo { height: 28px; }
  .hero-title { font-size: 26px; }
  .hero { padding: 50px 0 44px; }
  .adv-grid, .std-grid, .contact-grid, .form-grid { grid-template-columns: 1fr; }
  .photo-band, .psec-photos, .psec-photos.three, .psec-photos.two { grid-template-columns: 1fr; }
  .section { padding: 48px 0; }
  .sec-head h2 { font-size: 24px; }
  .sec-head { flex-wrap: wrap; gap: 6px 16px; }
  .sec-head p { margin-left: 0; width: 100%; }
}