:root {
  --sky: #0a90e8;
  --sky-deep: #0369b8;
  --sky-light: #e8f4fd;
  --ink: #17324d;
  --gray: #5d7285;
  --line: #e3edf5;
  --white: #ffffff;
  --radius: 14px;
  --max: 1180px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", "Noto Sans", "Noto Sans Thai", Tahoma, sans-serif;
  color: var(--ink);
  background: var(--white);
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--max); margin: 0 auto; padding: 0 20px;
  display: flex; align-items: center; gap: 28px; height: 68px;
}
.brand { display: flex; align-items: center; gap: 10px; font-size: 21px; font-weight: 700; color: var(--sky-deep); }
.brand img { height: 34px; }
.brand .en { color: var(--sky); font-size: 15px; letter-spacing: .5px; }
.main-nav { display: flex; gap: 4px; flex: 1; }
.main-nav a {
  padding: 8px 14px; border-radius: 8px; font-size: 15px; color: var(--ink); font-weight: 500;
  transition: .2s;
}
.main-nav a:hover { background: var(--sky-light); color: var(--sky-deep); }
.main-nav a.active { background: var(--sky); color: #fff; }
.lang-switch { display: flex; align-items: center; gap: 6px; }
.lang-switch select {
  padding: 7px 10px; border: 1px solid var(--line); border-radius: 8px;
  font-size: 14px; color: var(--ink); background: #fff; cursor: pointer; outline: none;
}
.nav-toggle { display: none; background: none; border: none; font-size: 24px; color: var(--sky-deep); cursor: pointer; }

/* ===== Hero ===== */
.hero {
  position: relative; color: #fff;
  background: linear-gradient(120deg, rgba(3,75,130,.82), rgba(10,144,232,.55)),
    url("../img/hero.jpg") center/cover no-repeat;
  padding: 120px 0 140px;
  text-align: center;
}
.hero h1 { font-size: 46px; font-weight: 800; letter-spacing: 1px; margin-bottom: 18px; }
.hero p { font-size: 19px; opacity: .94; max-width: 760px; margin: 0 auto 34px; }
.btn {
  display: inline-block; padding: 13px 34px; border-radius: 999px; font-size: 16px;
  font-weight: 600; transition: .2s; cursor: pointer; border: none;
}
.btn-primary { background: var(--sky); color: #fff; box-shadow: 0 8px 24px rgba(10,144,232,.35); }
.btn-primary:hover { background: var(--sky-deep); transform: translateY(-2px); }
.btn-ghost { background: rgba(255,255,255,.14); color: #fff; border: 1.5px solid rgba(255,255,255,.7); }
.btn-ghost:hover { background: rgba(255,255,255,.28); }

/* ===== Sections ===== */
.section { padding: 84px 0; }
.section.alt { background: var(--sky-light); }
.section-head { text-align: center; margin-bottom: 52px; }
.section-head .kicker { color: var(--sky); font-weight: 700; letter-spacing: 3px; text-transform: uppercase; font-size: 13px; }
.section-head h2 { font-size: 34px; margin-top: 8px; }
.section-head p { color: var(--gray); max-width: 720px; margin: 12px auto 0; }

.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: #fff; border-radius: var(--radius); overflow: hidden;
  box-shadow: 0 6px 24px rgba(23,50,77,.08); transition: .25s;
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-6px); box-shadow: 0 14px 34px rgba(10,144,232,.18); }
.card-img { height: 210px; background: #f2f7fb center/cover no-repeat; }
.card-body { padding: 20px 22px 24px; flex: 1; display: flex; flex-direction: column; }
.card-body h3 { font-size: 18px; margin-bottom: 6px; }
.card-body .tagline { color: var(--sky); font-size: 14px; font-weight: 600; margin-bottom: 10px; }
.card-body p { color: var(--gray); font-size: 14.5px; flex: 1; }
.specs { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.specs span {
  background: var(--sky-light); color: var(--sky-deep); font-size: 12.5px;
  padding: 4px 11px; border-radius: 999px; font-weight: 600;
}

/* stats */
.stats { display: grid; grid-template-columns: repeat(4,1fr); gap: 20px; margin-top: -60px; position: relative; z-index: 5; }
.stat {
  background: #fff; border-radius: var(--radius); text-align: center; padding: 28px 12px;
  box-shadow: 0 10px 30px rgba(23,50,77,.12);
}
.stat .num { font-size: 34px; font-weight: 800; color: var(--sky); }
.stat .label { color: var(--gray); font-size: 14px; margin-top: 4px; }

/* features */
.feature {
  background: #fff; border-radius: var(--radius); padding: 30px 26px;
  box-shadow: 0 6px 24px rgba(23,50,77,.08);
}
.feature .ico {
  width: 54px; height: 54px; border-radius: 14px; background: var(--sky-light);
  display: flex; align-items: center; justify-content: center; font-size: 26px; margin-bottom: 16px;
}
.feature h3 { font-size: 18px; margin-bottom: 8px; }
.feature p { color: var(--gray); font-size: 14.5px; }

/* factory */
.factory-card .card-img { height: 320px; }
.cap-list { margin-top: 12px; display: flex; flex-wrap: wrap; gap: 8px; }

/* certs strip */
.cert-row { display: flex; flex-wrap: wrap; gap: 18px; justify-content: center; }
.cert-item {
  width: 130px; background: #fff; border-radius: 12px; padding: 12px;
  box-shadow: 0 4px 16px rgba(23,50,77,.08); text-align: center;
}
.cert-item .thumb { height: 92px; border-radius: 8px; background: #f4f8fb center/contain no-repeat; margin-bottom: 8px; }
.cert-item .name { font-size: 12.5px; color: var(--gray); line-height: 1.4; }

/* filter chips */
.chips { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin-bottom: 40px; }
.chip {
  padding: 8px 20px; border-radius: 999px; border: 1.5px solid var(--line);
  background: #fff; font-size: 14.5px; cursor: pointer; transition: .2s; color: var(--gray);
}
.chip:hover { border-color: var(--sky); color: var(--sky); }
.chip.active { background: var(--sky); border-color: var(--sky); color: #fff; font-weight: 600; }

/* about page */
.prose { max-width: 860px; margin: 0 auto; color: var(--gray); font-size: 16px; }
.prose p { margin-bottom: 16px; }
.timeline { max-width: 760px; margin: 0 auto; }
.tl-item { display: flex; gap: 20px; padding: 18px 0; border-left: 3px solid var(--sky-light); padding-left: 24px; position: relative; }
.tl-item::before {
  content: ""; position: absolute; left: -9px; top: 26px; width: 15px; height: 15px;
  border-radius: 50%; background: var(--sky); border: 3px solid #fff; box-shadow: 0 0 0 2px var(--sky-light);
}
.tl-item .year { font-weight: 800; color: var(--sky); min-width: 90px; }

/* contact */
.contact-wrap { display: grid; grid-template-columns: 1fr 1.2fr; gap: 44px; }
.info-item { display: flex; gap: 14px; margin-bottom: 22px; align-items: flex-start; }
.info-item .ico {
  width: 44px; height: 44px; border-radius: 12px; background: var(--sky-light); color: var(--sky);
  display: flex; align-items: center; justify-content: center; font-size: 20px; flex-shrink: 0;
}
.info-item b { display: block; font-size: 15px; }
.info-item span { color: var(--gray); font-size: 14.5px; }
.form-card { background: #fff; border-radius: var(--radius); padding: 34px; box-shadow: 0 8px 30px rgba(23,50,77,.1); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-grid .full { grid-column: 1 / -1; }
.field label { display: block; font-size: 13.5px; font-weight: 600; margin-bottom: 6px; color: var(--ink); }
.field input, .field textarea {
  width: 100%; padding: 11px 14px; border: 1.5px solid var(--line); border-radius: 10px;
  font-size: 14.5px; font-family: inherit; outline: none; transition: .2s; background: #fbfdff;
}
.field input:focus, .field textarea:focus { border-color: var(--sky); background: #fff; }
.field textarea { min-height: 120px; resize: vertical; }
.form-msg { margin-top: 14px; font-size: 14px; display: none; }
.form-msg.ok { display: block; color: #0a9d58; }
.form-msg.err { display: block; color: #d94838; }

/* modal */
.modal-mask {
  position: fixed; inset: 0; background: rgba(10,30,50,.55); z-index: 200;
  display: none; align-items: center; justify-content: center; padding: 20px;
}
.modal-mask.show { display: flex; }
.modal {
  background: #fff; border-radius: 18px; max-width: 860px; width: 100%;
  max-height: 88vh; overflow-y: auto; position: relative;
}
.modal-close {
  position: absolute; right: 14px; top: 12px; font-size: 26px; background: none; border: none;
  color: #666; cursor: pointer; z-index: 2; line-height: 1;
}
.modal-img { height: 340px; background: #f2f7fb center/cover no-repeat; }
.modal-body { padding: 26px 30px 34px; }
.modal-body h3 { font-size: 24px; }
.modal-body .tagline { color: var(--sky); font-weight: 600; margin: 4px 0 14px; }
.modal-body p.sum { color: var(--gray); margin-bottom: 18px; }
.spec-table { width: 100%; border-collapse: collapse; margin-top: 8px; }
.spec-table td { padding: 10px 12px; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.spec-table td:first-child { color: var(--gray); width: 40%; }
.spec-table td:last-child { font-weight: 600; }

/* footer */
.site-footer { background: #0c2a45; color: #b9cfdf; margin-top: 40px; }
.footer-inner {
  max-width: var(--max); margin: 0 auto; padding: 54px 20px 28px;
  display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 40px;
}
.site-footer h4 { color: #fff; font-size: 16px; margin-bottom: 14px; }
.site-footer a { display: block; padding: 4px 0; font-size: 14px; color: #b9cfdf; }
.site-footer a:hover { color: #fff; }
.footer-brand { display: flex; align-items: center; gap: 10px; color: #fff; font-size: 20px; font-weight: 700; margin-bottom: 14px; }
.footer-brand img { height: 32px; }
.site-footer p { font-size: 14px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.12); padding: 18px 20px; text-align: center;
  font-size: 13px; color: #7e97a9;
}

/* responsive */
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2,1fr); }
  .contact-wrap { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .main-nav {
    display: none; position: absolute; top: 68px; left: 0; right: 0;
    background: #fff; flex-direction: column; padding: 12px 20px; border-bottom: 1px solid var(--line);
  }
  .main-nav.open { display: flex; }
  .nav-toggle { display: block; }
  .hero h1 { font-size: 32px; }
  .form-grid { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
}

/* ===== hero kicker / contact info tweaks ===== */
.hero .kicker {
  color: rgba(255,255,255,.88); font-weight: 700; letter-spacing: 3px;
  text-transform: uppercase; font-size: 13px; margin-bottom: 16px;
}
.info-item strong { display: block; color: var(--sky-deep); font-size: 15px; margin-bottom: 4px; }
.info-item p { color: var(--gray); font-size: 15px; margin: 0; }
.chips { display: flex; flex-wrap: wrap; gap: 10px; }
.chip {
  padding: 8px 22px; border-radius: 999px; border: 1.5px solid var(--sky);
  background: #fff; color: var(--sky-deep); font-weight: 600; cursor: pointer; transition: .2s;
}
.chip:hover { background: #eaf5fd; }
.chip.active { background: var(--sky); color: #fff; }
.stats > .container { display: grid; grid-template-columns: repeat(4,1fr); gap: 20px; }

/* ===== certs: PPT-style dense image grid ===== */
#homeCerts.cert-grid, .cert-grid { display: grid !important; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.cert-item { width: auto; }
.cert-item .thumb { height: 150px; background: #fff center/contain no-repeat; box-shadow: 0 4px 16px rgba(23,50,77,.08); border-radius: 12px; padding: 10px; box-sizing: border-box; }
@media (max-width: 900px) { .cert-grid, #homeCerts.cert-grid { grid-template-columns: repeat(3, 1fr) !important; } }
@media (max-width: 600px) { .cert-grid, #homeCerts.cert-grid { grid-template-columns: repeat(2, 1fr) !important; } .cert-item .thumb { height: 110px; } }

/* ===== factory: large-image layout ===== */
.factory-block { margin-bottom: 56px; }
.factory-hero { width: 100%; height: 440px; border-radius: 16px; background: #dfe9f2 center/cover no-repeat; box-shadow: 0 8px 28px rgba(23,50,77,.12); }
.factory-head { display: flex; align-items: baseline; gap: 16px; flex-wrap: wrap; margin-top: 22px; }
.factory-head h3 { font-size: 24px; color: var(--sky-deep); margin: 0; }
.factory-desc { color: var(--gray); font-size: 15.5px; line-height: 1.8; max-width: 900px; }
.factory-gallery { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; margin-top: 18px; }
.fg-item { height: 300px; border-radius: 12px; background: #eef4f9 center/cover no-repeat; }
@media (max-width: 700px) { .factory-hero { height: 230px; } .fg-item { height: 170px; } .factory-gallery { grid-template-columns: 1fr; } }

/* ===== product detail page ===== */
.back-link { display: inline-block; color: var(--sky-deep); font-weight: 600; font-size: 15px; margin-bottom: 20px; text-decoration: none; }
.back-link:hover { text-decoration: underline; }
.detail-hero { width: 100%; height: 460px; border-radius: 16px; background: #eef4f9 center/contain no-repeat; box-shadow: 0 8px 28px rgba(23,50,77,.12); }
.detail-head { display: flex; align-items: baseline; gap: 18px; flex-wrap: wrap; margin-top: 26px; }
.detail-head h1 { font-size: 28px; color: var(--sky-deep); margin: 0; }
.detail-sum { color: var(--gray); font-size: 16px; line-height: 1.85; max-width: 920px; }
.detail-sec { color: var(--sky-deep); font-size: 20px; margin: 36px 0 14px; }
.detail-table td:first-child { width: 40%; color: var(--gray); }
@media (max-width: 700px) { .detail-hero { height: 240px; } .detail-head h1 { font-size: 22px; } }

/* ===== 图片完整性：产品图一律完整显示不裁剪 ===== */
.card-img { background: #fff center/contain no-repeat; }
.fg-item { background: #fff center/contain no-repeat; }
.modal-img { background: #fff center/contain no-repeat; }