/* === YS / EverGrowing Brand Tokens === */
:root {
  --c-primary: #1a3a8f;
  --c-accent:  #ff6a1a;
  --c-bg:      #f7f8fc;
  --c-card:    #ffffff;
  --c-text:    #1d2333;
  --c-muted:   #6b7388;
  --c-line:    #e5e8f0;
  --c-success: #16a34a;
  --shadow-sm: 0 1px 3px rgba(20, 30, 60, .06), 0 1px 2px rgba(20, 30, 60, .04);
  --shadow-md: 0 6px 18px rgba(20, 30, 60, .08);
  --radius:    14px;
  --font:      -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei",
               "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--font);
  background: var(--c-bg);
  color: var(--c-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* === Layout === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* === Header === */
.site-header {
  background: var(--c-card);
  border-bottom: 1px solid var(--c-line);
  position: sticky; top: 0; z-index: 50;
  box-shadow: var(--shadow-sm);
}
.site-header .container { display: flex; align-items: center; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
.brand .logo {
  width: 36px; height: 36px; border-radius: 8px;
  background: linear-gradient(135deg, var(--c-primary) 0%, var(--c-accent) 100%);
  display: grid; place-items: center; color: #fff; font-size: 18px; font-weight: 800;
}
.brand small { color: var(--c-muted); font-weight: 400; font-size: 12px; margin-left: 4px; }
nav.primary { margin-left: auto; display: flex; gap: 4px; }
nav.primary a {
  padding: 8px 14px; border-radius: 8px; font-size: 14px;
  color: var(--c-text); font-weight: 500;
}
nav.primary a:hover, nav.primary a.active { background: rgba(26, 58, 143, .08); color: var(--c-primary); }
.lang-switch { margin-left: 8px; display: flex; gap: 2px; }
.lang-switch button {
  background: transparent; border: 1px solid var(--c-line); padding: 4px 10px;
  font-size: 12px; border-radius: 6px; cursor: pointer; color: var(--c-muted);
}
.lang-switch button.active { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }

/* === Hero === */
.hero {
  background: linear-gradient(135deg, #1a3a8f 0%, #2547b0 60%, #ff6a1a 130%);
  color: #fff; padding: 96px 0 96px; position: relative; overflow: hidden;
}
.hero::after {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(800px 400px at 80% 30%, rgba(255,106,26,.4), transparent);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 1; }
.hero h1 { font-size: 48px; line-height: 1.15; margin: 0 0 16px; font-weight: 800; }
.hero p.lede { font-size: 18px; opacity: .9; max-width: 640px; margin: 0 0 32px; }
.hero .cta { display: flex; gap: 12px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 22px; border-radius: 10px; font-weight: 600; font-size: 15px;
  cursor: pointer; border: 0; transition: transform .12s ease, box-shadow .12s ease;
}
.btn-primary { background: var(--c-accent); color: #fff; }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 8px 20px rgba(255, 106, 26, .4); }
.btn-ghost { background: rgba(255,255,255,.12); color: #fff; border: 1px solid rgba(255,255,255,.3); }
.btn-ghost:hover { background: rgba(255,255,255,.2); }
.hero-stats { display: flex; gap: 40px; margin-top: 56px; }
.hero-stats .stat .n { font-size: 32px; font-weight: 800; color: #ffd9bf; }
.hero-stats .stat .l { font-size: 13px; opacity: .8; }

/* === Sections === */
section { padding: 80px 0; }
section.tight { padding: 48px 0; }
h2.section-title { font-size: 32px; font-weight: 800; margin: 0 0 8px; }
p.section-sub { color: var(--c-muted); font-size: 16px; margin: 0 0 40px; max-width: 640px; }

/* === Category Cards === */
.cats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.cat {
  background: var(--c-card); border-radius: var(--radius); padding: 28px;
  box-shadow: var(--shadow-sm); transition: transform .15s, box-shadow .15s;
  cursor: pointer; border: 1px solid var(--c-line);
}
.cat:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--c-primary); }
.cat .icon { font-size: 36px; margin-bottom: 12px; }
.cat h3 { margin: 0 0 8px; font-size: 20px; }
.cat p { color: var(--c-muted); font-size: 14px; margin: 0; }
.cat .more { display: inline-flex; margin-top: 16px; color: var(--c-primary); font-weight: 600; font-size: 14px; }

/* === Product Grid === */
.products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.product {
  background: var(--c-card); border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow-sm); border: 1px solid var(--c-line);
  transition: transform .15s, box-shadow .15s;
  display: flex; flex-direction: column;
}
.product:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.product .img {
  aspect-ratio: 4/3; background: #f0f2f7 center/contain no-repeat;
  border-bottom: 1px solid var(--c-line);
  display: grid; place-items: center;
}
.product .img img { width: 90%; height: 90%; object-fit: contain; }
.product .body { padding: 18px; flex: 1; display: flex; flex-direction: column; }
.product .model { font-size: 12px; font-weight: 700; color: var(--c-accent); text-transform: uppercase; letter-spacing: .04em; }
.product h4 { margin: 4px 0 8px; font-size: 16px; line-height: 1.4; }
.product .spec { font-size: 13px; color: var(--c-muted); margin: 0 0 12px; }
.product .feature { font-size: 13px; padding: 6px 10px; background: rgba(26, 58, 143, .06); color: var(--c-primary); border-radius: 6px; display: inline-block; }

/* === Why Us === */
.why { background: var(--c-card); border-top: 1px solid var(--c-line); border-bottom: 1px solid var(--c-line); }
.why-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.why-item .ic {
  width: 48px; height: 48px; border-radius: 12px;
  background: linear-gradient(135deg, var(--c-primary), #2c5cdd);
  color: #fff; display: grid; place-items: center; font-size: 22px; margin-bottom: 14px;
}
.why-item h4 { margin: 0 0 6px; font-size: 16px; }
.why-item p { color: var(--c-muted); font-size: 14px; margin: 0; }

/* === Contact === */
.contact { background: linear-gradient(135deg, #1a3a8f 0%, #2547b0 100%); color: #fff; }
.contact h2 { color: #fff; }
.contact p.section-sub { color: rgba(255,255,255,.8); }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.contact-form { background: #fff; color: var(--c-text); border-radius: var(--radius); padding: 28px; }
.contact-form input, .contact-form textarea, .contact-form select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--c-line); border-radius: 8px;
  font: inherit; margin-bottom: 12px; background: #fff;
}
.contact-form label { font-size: 13px; color: var(--c-muted); display: block; margin-bottom: 4px; }
.contact-form .btn { width: 100%; justify-content: center; }
.contact-info p { margin: 0 0 14px; font-size: 15px; }
.contact-info strong { display: block; font-size: 13px; opacity: .7; font-weight: 500; margin-bottom: 2px; }

/* === Footer === */
footer { background: #0d1f4d; color: rgba(255,255,255,.7); padding: 40px 0 24px; font-size: 13px; }
footer .container { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 16px; }
footer .legal { opacity: .6; }

/* === Page: product detail === */
.product-detail { padding: 40px 0 80px; }
.breadcrumb { font-size: 13px; color: var(--c-muted); margin-bottom: 16px; }
.breadcrumb a { color: var(--c-primary); }
.detail-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: start; }
.detail-img { background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius); aspect-ratio: 1; display: grid; place-items: center; padding: 20px; }
.detail-img img { max-width: 100%; max-height: 100%; object-fit: contain; }
.detail-info h1 { font-size: 28px; margin: 0 0 8px; }
.detail-info .model-tag { display: inline-block; padding: 4px 10px; background: var(--c-accent); color: #fff; border-radius: 6px; font-size: 12px; font-weight: 700; letter-spacing: .04em; margin-bottom: 12px; }
.spec-table { width: 100%; border-collapse: collapse; margin-top: 20px; font-size: 14px; }
.spec-table th, .spec-table td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--c-line); }
.spec-table th { background: rgba(26, 58, 143, .04); width: 36%; color: var(--c-muted); font-weight: 500; }
.tag-row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 16px; }
.tag { padding: 4px 10px; background: rgba(22, 163, 74, .1); color: var(--c-success); font-size: 12px; border-radius: 6px; }

/* === Filter bar === */
.filter-bar { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 28px; }
.filter-bar button {
  background: #fff; border: 1px solid var(--c-line); padding: 8px 16px;
  border-radius: 999px; cursor: pointer; font-size: 14px; color: var(--c-text);
}
.filter-bar button.active { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }

/* === Responsive === */
@media (max-width: 960px) {
  .hero h1 { font-size: 36px; }
  .cats, .products { grid-template-columns: 1fr 1fr; }
  .why-grid { grid-template-columns: 1fr 1fr; }
  .detail-grid, .contact-grid { grid-template-columns: 1fr; }
  .hero-stats { gap: 24px; flex-wrap: wrap; }
}
@media (max-width: 600px) {
  .hero { padding: 64px 0; }
  .hero h1 { font-size: 28px; }
  .cats, .products, .why-grid { grid-template-columns: 1fr; }
  nav.primary a { padding: 6px 8px; font-size: 13px; }
}