/* ==========================================================================
   斯达房屋官网 - 全站样式
   设计语言：高级简约 + 工业风
   主色：深黑 #1a1a1a / 工业橙 #FF6B1A
   ========================================================================== */

* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --color-primary: #1a1a1a;
  --color-accent: #FF6B1A;
  --color-accent-dark: #E55A0E;
  --color-text: #222;
  --color-text-light: #666;
  --color-text-mute: #999;
  --color-bg: #FFFFFF;
  --color-bg-soft: #F7F7F5;
  --color-bg-dark: #111;
  --color-border: #E8E8E8;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
  --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
  --shadow-lg: 0 16px 48px rgba(0,0,0,0.12);
  --radius: 4px;
  --radius-lg: 8px;
  --container: 1440px;
  --transition: all 0.25s ease;
}

html { scroll-behavior: smooth; font-size: 17px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 32px; }

/* ===== Typography ===== */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.25; color: var(--color-primary); letter-spacing: -0.02em; }
h1 { font-size: 56px; }
h2 { font-size: 44px; }
h3 { font-size: 26px; }
h4 { font-size: 20px; }

.section-title { text-align: center; margin-bottom: 20px; }
.section-subtitle { text-align: center; color: var(--color-text-light); font-size: 18px; margin-bottom: 64px; max-width: 760px; margin-left: auto; margin-right: auto; line-height: 1.7; }
.section-tag { display: inline-block; color: var(--color-accent); font-size: 14px; font-weight: 700; letter-spacing: 0.15em; text-transform: uppercase; margin-bottom: 14px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}
.site-header .container { display: flex; align-items: center; height: 88px; gap: 32px; }

.logo { display: flex; align-items: baseline; gap: 12px; flex-shrink: 0; }
.logo-cn { font-size: 32px; font-weight: 900; letter-spacing: 0.08em; color: var(--color-primary); }
.logo-en { font-size: 11px; font-weight: 700; letter-spacing: 0.25em; color: var(--color-accent); text-transform: uppercase; }

.main-nav { display: flex; gap: 28px; flex: 1; }
.main-nav a {
  position: relative; font-size: 15px; font-weight: 600; color: var(--color-text);
  padding: 12px 0; white-space: nowrap; letter-spacing: 0.02em;
}
.main-nav a:hover, .main-nav a.active { color: var(--color-accent); }
.main-nav a.active::after {
  content: ''; position: absolute; bottom: -28px; left: 0; right: 0;
  height: 3px; background: var(--color-accent); border-radius: 2px;
}

.header-cta { display: flex; align-items: center; gap: 16px; flex-shrink: 0; }
.phone-btn {
  display: flex; align-items: center; gap: 8px;
  font-size: 17px; font-weight: 700; color: var(--color-primary);
}
.phone-btn .icon { color: var(--color-accent); font-size: 20px; }
.phone-btn:hover { color: var(--color-accent); }

.mobile-menu-btn { display: none; font-size: 26px; color: var(--color-primary); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 16px 36px; font-size: 16px; font-weight: 600;
  border-radius: var(--radius); transition: var(--transition);
  white-space: nowrap; cursor: pointer;
}
.btn-primary { background: var(--color-accent); color: #fff; }
.btn-primary:hover { background: var(--color-accent-dark); transform: translateY(-2px); box-shadow: 0 8px 20px rgba(255,107,26,0.35); }
.btn-dark { background: var(--color-primary); color: #fff; }
.btn-dark:hover { background: #000; transform: translateY(-2px); }
.btn-outline { background: transparent; color: var(--color-primary); border: 1.5px solid var(--color-primary); }
.btn-outline:hover { background: var(--color-primary); color: #fff; }
.btn-outline-light { background: transparent; color: #fff; border: 1.5px solid rgba(255,255,255,0.5); }
.btn-outline-light:hover { background: #fff; color: var(--color-primary); border-color: #fff; }
.btn-lg { padding: 20px 44px; font-size: 17px; }
.btn-sm { padding: 11px 22px; font-size: 15px; }

/* ===== Hero ===== */
.hero {
  position: relative; min-height: 720px;
  background: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 100%);
  color: #fff; overflow: hidden;
  display: flex; align-items: center;
}
.hero::before {
  content: ''; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 20% 50%, rgba(255,107,26,0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255,107,26,0.1) 0%, transparent 40%);
}
.hero-grid { position: absolute; inset: 0; opacity: 0.04;
  background-image:
    linear-gradient(#fff 1px, transparent 1px),
    linear-gradient(90deg, #fff 1px, transparent 1px);
  background-size: 60px 60px;
}
.hero-inner { position: relative; z-index: 2; padding: 96px 0; width: 100%; }
.hero h1 { color: #fff; font-size: 68px; margin-bottom: 28px; line-height: 1.15; }
.hero h1 .accent { color: var(--color-accent); }
.hero-sub { font-size: 21px; color: rgba(255,255,255,0.78); max-width: 680px; margin-bottom: 44px; line-height: 1.7; }
.hero-keywords { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 44px; }
.hero-keywords span {
  padding: 8px 18px; font-size: 14px;
  background: rgba(255,255,255,0.08); border: 1px solid rgba(255,255,255,0.15);
  border-radius: 24px; color: rgba(255,255,255,0.85);
}
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; }

.hero-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px;
  margin-top: 72px; padding-top: 48px;
  border-top: 1px solid rgba(255,255,255,0.1);
}
.hero-stat .num { font-size: 48px; font-weight: 800; color: var(--color-accent); line-height: 1; }
.hero-stat .num .unit { font-size: 20px; margin-left: 6px; color: #fff; opacity: 0.6; }
.hero-stat .label { font-size: 14px; color: rgba(255,255,255,0.6); margin-top: 12px; letter-spacing: 0.05em; }

/* ===== Page Hero (二级页头部) ===== */
.page-hero {
  background: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 100%);
  color: #fff; padding: 96px 0 80px;
  position: relative; overflow: hidden;
}
.page-hero::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at 70% 30%, rgba(255,107,26,0.12), transparent 50%);
}
.page-hero .container { position: relative; z-index: 2; }
.page-hero h1 { color: #fff; font-size: 52px; margin-bottom: 20px; line-height: 1.2; }
.page-hero .sub { color: rgba(255,255,255,0.72); font-size: 19px; max-width: 760px; line-height: 1.7; }
.breadcrumb { font-size: 14px; color: rgba(255,255,255,0.5); margin-bottom: 28px; }
.breadcrumb a { color: rgba(255,255,255,0.7); }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb .sep { margin: 0 10px; }

/* ===== Sections ===== */
section { padding: 120px 0; }
section.tight { padding: 80px 0; }
section.bg-soft { background: var(--color-bg-soft); }
section.bg-dark { background: var(--color-bg-dark); color: #fff; }
section.bg-dark h2, section.bg-dark h3 { color: #fff; }

/* ===== Product Grid ===== */
.product-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.product-card {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  overflow: hidden; transition: var(--transition); display: flex; flex-direction: column;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: var(--color-accent); }
.product-card .img {
  aspect-ratio: 4/3; background: linear-gradient(135deg, #2a2a2a, #444);
  position: relative; overflow: hidden;
  display: flex; align-items: center; justify-content: center;
  color: rgba(255,255,255,0.3); font-size: 15px;
}
.card-img {
  width: 100%; height: 100%; aspect-ratio: 4/3; object-fit: cover; display: block;
}
.product-card .img::before {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(255,107,26,0.1), transparent);
}
.product-card .img-label {
  position: absolute; bottom: 12px; left: 12px;
  font-size: 12px; color: rgba(255,255,255,0.4);
  border: 1px dashed rgba(255,255,255,0.2); padding: 4px 10px; border-radius: 2px;
}
.product-card .body { padding: 28px; flex: 1; display: flex; flex-direction: column; }
.product-card h3 { font-size: 22px; margin-bottom: 10px; }
.product-card .desc { font-size: 15px; color: var(--color-text-light); margin-bottom: 18px; flex: 1; line-height: 1.7; }
.product-card .meta { display: flex; gap: 14px; font-size: 13px; color: var(--color-text-mute); margin-bottom: 18px; }
.product-card .meta span::before { content: '·'; margin-right: 6px; color: var(--color-accent); font-weight: bold; }
.product-card .meta span:first-child::before { content: ''; margin: 0; }
.product-card .more { font-size: 15px; color: var(--color-accent); font-weight: 600; margin-top: auto; }
.product-card .more::after { content: ' →'; transition: var(--transition); }
.product-card:hover .more::after { margin-left: 4px; }

/* ===== Solution Grid ===== */
.solution-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.solution-card {
  position: relative; padding: 44px 36px;
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  transition: var(--transition);
}
.solution-card:hover { background: var(--color-primary); color: #fff; transform: translateY(-4px); }
.solution-card:hover h3 { color: #fff; }
.solution-card:hover .icon { color: var(--color-accent); }
.solution-card .icon { font-size: 36px; color: var(--color-accent); margin-bottom: 24px; }
.solution-card h3 { font-size: 22px; margin-bottom: 14px; transition: var(--transition); }
.solution-card .desc { font-size: 15px; color: inherit; opacity: 0.75; margin-bottom: 22px; line-height: 1.75; }
.solution-card ul { font-size: 14px; opacity: 0.85; line-height: 1.9; }
.solution-card ul li { padding-left: 18px; position: relative; margin-bottom: 6px; }
.solution-card ul li::before { content: '▸'; position: absolute; left: 0; color: var(--color-accent); }

/* ===== Case Grid ===== */
.case-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.case-grid.cols-4 { grid-template-columns: repeat(4, 1fr); gap: 24px; }
.case-card {
  background: #fff; border-radius: var(--radius-lg); overflow: hidden;
  transition: var(--transition); border: 1px solid var(--color-border);
}
.case-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.case-card .img {
  aspect-ratio: 16/10; background: linear-gradient(135deg, #333, #1a1a1a);
  position: relative; overflow: hidden;
}
.case-card .img::after {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(180deg, transparent 50%, rgba(0,0,0,0.6));
}
.case-card .tag {
  position: absolute; top: 16px; left: 16px; z-index: 2;
  background: var(--color-accent); color: #fff;
  font-size: 13px; font-weight: 600; padding: 5px 12px; border-radius: 2px;
}
.case-card .img-label {
  position: absolute; bottom: 16px; left: 16px; z-index: 2;
  font-size: 13px; color: rgba(255,255,255,0.7);
}
.case-card .body { padding: 28px; }
.case-card h3 { font-size: 20px; margin-bottom: 12px; }
.case-card .meta-row { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 14px; }
.case-card .meta-row span {
  font-size: 13px; padding: 4px 12px;
  background: var(--color-bg-soft); color: var(--color-text-light);
  border-radius: 2px;
}
.case-card .desc { font-size: 15px; color: var(--color-text-light); line-height: 1.7; }

/* ===== Guide List ===== */
.guide-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.guide-card {
  background: #fff; padding: 32px 36px; border-radius: var(--radius-lg);
  border: 1px solid var(--color-border); transition: var(--transition);
  display: flex; gap: 24px; align-items: flex-start;
}
.guide-card:hover { border-color: var(--color-accent); transform: translateX(4px); }
.guide-card .num {
  flex-shrink: 0; font-size: 38px; font-weight: 800;
  color: var(--color-bg-soft); line-height: 1;
  -webkit-text-stroke: 1px var(--color-accent);
}
.guide-card h3 { font-size: 19px; margin-bottom: 10px; line-height: 1.4; }
.guide-card .desc { font-size: 15px; color: var(--color-text-light); margin-bottom: 14px; line-height: 1.7; }
.guide-card .read { font-size: 14px; color: var(--color-accent); font-weight: 600; }

/* ===== Trust / Stats ===== */
.trust-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; padding: 56px 0; }
.trust-item { text-align: center; }
.trust-item .num { font-size: 56px; font-weight: 800; color: var(--color-accent); line-height: 1; }
.trust-item .num small { font-size: 20px; color: var(--color-primary); margin-left: 4px; }
.trust-item .label { font-size: 15px; color: var(--color-text-light); margin-top: 14px; }

/* ===== Process Steps ===== */
.process-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 18px; position: relative; }
.process-step {
  text-align: center; padding: 28px 18px;
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  position: relative;
}
.process-step .step-num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--color-accent); color: #fff;
  font-weight: 800; font-size: 19px; margin-bottom: 18px;
}
.process-step h4 { font-size: 17px; margin-bottom: 8px; }
.process-step .desc { font-size: 14px; color: var(--color-text-light); line-height: 1.6; }

/* ===== Factory Strengths ===== */
.strength-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.strength-card {
  background: var(--color-primary); color: #fff; padding: 44px 36px; border-radius: var(--radius-lg);
  position: relative; overflow: hidden;
}
.strength-card::before {
  content: ''; position: absolute; top: -40px; right: -40px;
  width: 160px; height: 160px; border-radius: 50%;
  background: radial-gradient(circle, rgba(255,107,26,0.2), transparent 70%);
}
.strength-card .num { font-size: 14px; color: var(--color-accent); font-weight: 700; letter-spacing: 0.18em; margin-bottom: 14px; }
.strength-card h3 { color: #fff; font-size: 24px; margin-bottom: 14px; line-height: 1.35; }
.strength-card p { color: rgba(255,255,255,0.72); font-size: 15px; line-height: 1.85; }

/* ===== FAQ ===== */
.faq-list { max-width: 920px; margin: 0 auto; }
.faq-item {
  border-bottom: 1px solid var(--color-border);
  padding: 28px 0; cursor: pointer;
}
.faq-q { display: flex; justify-content: space-between; align-items: center; font-size: 19px; font-weight: 600; }
.faq-q::after { content: '+'; font-size: 28px; color: var(--color-accent); transition: var(--transition); }
.faq-item.open .faq-q::after { transform: rotate(45deg); }
.faq-a { font-size: 16px; color: var(--color-text-light); line-height: 1.85; max-height: 0; overflow: hidden; transition: max-height 0.3s ease, padding 0.3s ease; }
.faq-item.open .faq-a { max-height: 500px; padding-top: 18px; }

/* ===== CTA Banner ===== */
.cta-banner {
  background: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 100%);
  color: #fff; padding: 96px 0; position: relative; overflow: hidden;
}
.cta-banner::before {
  content: ''; position: absolute; right: -100px; top: -100px;
  width: 400px; height: 400px; border-radius: 50%;
  background: radial-gradient(circle, rgba(255,107,26,0.2), transparent 70%);
}
.cta-banner .inner { position: relative; z-index: 2; display: flex; align-items: center; justify-content: space-between; gap: 40px; flex-wrap: wrap; }
.cta-banner h2 { color: #fff; font-size: 38px; margin-bottom: 12px; line-height: 1.25; }
.cta-banner p { color: rgba(255,255,255,0.7); font-size: 18px; }
.cta-banner .actions { display: flex; gap: 16px; flex-shrink: 0; flex-wrap: wrap; }

/* ===== Form ===== */
.contact-form { background: #fff; padding: 40px; border-radius: var(--radius-lg); box-shadow: var(--shadow-md); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 16px; }
.form-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; color: var(--color-primary); }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 12px 16px; font-size: 15px; font-family: inherit;
  border: 1px solid var(--color-border); border-radius: var(--radius);
  transition: var(--transition); background: #fff;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--color-accent); box-shadow: 0 0 0 3px rgba(255,107,26,0.1);
}
.form-group textarea { min-height: 110px; resize: vertical; }

/* ===== Footer ===== */
.site-footer { background: #0d0d0d; color: rgba(255,255,255,0.65); padding: 72px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1.4fr; gap: 48px; padding-bottom: 56px; }
.footer-col h4 { color: #fff; font-size: 16px; font-weight: 700; margin-bottom: 20px; }
.footer-col ul li { margin-bottom: 12px; font-size: 15px; }
.footer-col ul li a:hover { color: var(--color-accent); }
.footer-brand .logo { margin-bottom: 18px; }
.footer-brand .logo-cn { color: #fff; }
.footer-brand p { font-size: 15px; line-height: 1.85; margin-bottom: 18px; }
.footer-contact div { margin-bottom: 10px; font-size: 15px; }
.footer-contact .label { color: var(--color-text-mute); margin-right: 6px; }
.footer-contact-row { display: flex; align-items: flex-start; }
.footer-contact-row .label { min-width: 52px; flex-shrink: 0; }
.qr-code {
  width: 120px; height: 120px;
  background: #fff; color: #1a1a1a; border-radius: 4px;
  display: flex; align-items: center; justify-content: center;
  font-size: 13px; text-align: center; line-height: 1.5;
}
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 28px 0; font-size: 14px; color: var(--color-text-mute);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 16px;
}

/* ===== Floating Contact (PC) ===== */
.float-contact {
  position: fixed; right: 24px; bottom: 100px; z-index: 90;
  display: flex; flex-direction: column; gap: 12px;
}
.float-btn {
  width: 56px; height: 56px; border-radius: 50%;
  background: var(--color-accent); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; box-shadow: var(--shadow-md);
  transition: var(--transition); position: relative;
}
.float-btn:hover { transform: scale(1.1); }
.float-btn .tip {
  position: absolute; right: 70px; top: 50%; transform: translateY(-50%);
  background: #1a1a1a; color: #fff; padding: 8px 14px;
  border-radius: var(--radius); font-size: 13px; white-space: nowrap;
  opacity: 0; pointer-events: none; transition: var(--transition);
}
.float-btn:hover .tip { opacity: 1; right: 64px; }
.float-btn.wechat { background: #07C160; }
.float-btn.top { background: #fff; color: var(--color-primary); border: 1px solid var(--color-border); font-size: 18px; }

/* ===== Mobile CTA Bar ===== */
.mobile-cta-bar {
  display: none;
  position: fixed; bottom: 0; left: 0; right: 0; z-index: 99;
  background: #fff; border-top: 1px solid var(--color-border);
  box-shadow: 0 -4px 16px rgba(0,0,0,0.06);
}
.mobile-cta-bar a {
  flex: 1; padding: 14px 0; text-align: center;
  font-size: 14px; font-weight: 600;
  display: flex; align-items: center; justify-content: center; gap: 6px;
}
.mobile-cta-bar a.call { color: var(--color-primary); }
.mobile-cta-bar a.wechat { background: var(--color-accent); color: #fff; }
.mobile-cta-bar a.wechat::before { content: '💬'; }
.mobile-cta-bar a.call::before { content: '📞'; color: var(--color-accent); }

/* ===== Detail Pages ===== */
.detail-layout { display: grid; grid-template-columns: 1fr 320px; gap: 48px; }
.detail-main { min-width: 0; }
.detail-sidebar { position: sticky; top: 100px; align-self: start; }
.detail-sidebar .card { background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg); padding: 28px; margin-bottom: 20px; }
.detail-sidebar .card h4 { font-size: 17px; margin-bottom: 16px; }

.detail-hero { aspect-ratio: 16/9; background: linear-gradient(135deg, #333, #1a1a1a); border-radius: var(--radius-lg); margin-bottom: 36px; position: relative; display: flex; align-items: center; justify-content: center; color: rgba(255,255,255,0.4); font-size: 15px; overflow: hidden; }

/* Image Slider */
.image-slider { position: relative; width: 100%; height: 100%; }
.slider-wrapper { position: relative; width: 100%; height: 100%; }
.slider-wrapper .slide {
  position: absolute; inset: 0;
  width: 100%; height: 100%; object-fit: cover;
  opacity: 0; transition: opacity 0.6s ease;
}
.slider-wrapper video.slide {
  background: #000;
}
.slider-wrapper .slide.active { opacity: 1; }
.slider-btn {
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(0,0,0,0.5); color: #fff;
  border: 2px solid rgba(255,255,255,0.3);
  font-size: 20px; cursor: pointer; z-index: 10;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.2s;
}
.slider-btn:hover { background: rgba(0,0,0,0.7); border-color: #fff; }
.slider-btn.prev { left: 20px; }
.slider-btn.next { right: 20px; }
.slider-dots {
  position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 10px; z-index: 10;
}
.slider-dots .dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: rgba(255,255,255,0.4); cursor: pointer;
  transition: all 0.2s;
}
.slider-dots .dot.active { background: #fff; transform: scale(1.2); }

.sound-toggle {
  position: absolute; bottom: 20px; right: 20px; z-index: 10;
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(0,0,0,0.5); color: #fff; font-size: 20px;
  border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: background 0.2s;
}
.sound-toggle:hover { background: rgba(0,0,0,0.7); }

.video-slider .slide {
  width: 100%; height: 100%; object-fit: cover;
  display: none;
}
.video-slider .slide.active { display: block; }

.spec-table { width: 100%; border-collapse: collapse; margin: 28px 0; }
.spec-table th, .spec-table td { padding: 16px 20px; text-align: left; border-bottom: 1px solid var(--color-border); font-size: 16px; line-height: 1.7; }
.spec-table th { background: var(--color-bg-soft); font-weight: 700; width: 30%; }

.article-content h2 { font-size: 32px; margin: 56px 0 20px; padding-left: 18px; border-left: 4px solid var(--color-accent); line-height: 1.3; }
.article-content h3 { font-size: 22px; margin: 36px 0 14px; }
.article-content p { margin-bottom: 18px; font-size: 17px; line-height: 1.95; color: #333; }
.article-content ul { margin: 18px 0; padding-left: 28px; }
.article-content ul li { list-style: disc; margin-bottom: 10px; line-height: 1.85; font-size: 17px; }
.article-content blockquote {
  border-left: 4px solid var(--color-accent); background: var(--color-bg-soft);
  padding: 22px 28px; margin: 28px 0; font-size: 17px; color: var(--color-text-light);
  border-radius: 0 var(--radius) var(--radius) 0; line-height: 1.8;
}
.article-content .highlight-box {
  background: linear-gradient(135deg, #FFF7F0, #FFEFE0);
  border: 1px solid #FFD9B8; border-radius: var(--radius-lg);
  padding: 28px 32px; margin: 32px 0;
}
.article-content .highlight-box h4 { color: var(--color-accent-dark); margin-bottom: 14px; font-size: 18px; }

/* ===== Tabs / Anchors ===== */
.anchor-nav {
  display: flex; gap: 4px; padding: 6px; margin-bottom: 36px;
  background: var(--color-bg-soft); border-radius: var(--radius);
  overflow-x: auto;
}
.anchor-nav a {
  padding: 12px 24px; font-size: 15px; font-weight: 600;
  border-radius: var(--radius); white-space: nowrap; color: var(--color-text-light);
}
.anchor-nav a.active, .anchor-nav a:hover { background: #fff; color: var(--color-accent); box-shadow: var(--shadow-sm); }

/* ===== Responsive ===== */

/* 大屏优化 (1600px+) */
@media (min-width: 1600px) {
  .container { max-width: 1600px; padding: 0 48px; }
  .product-grid { gap: 32px; }
  .solution-grid, .case-grid { gap: 32px; }
}

/* 桌面端优化 (1181px - 1599px) */
@media (min-width: 1181px) {
  .product-grid { grid-template-columns: repeat(4, 1fr); }
  .solution-grid, .case-grid { grid-template-columns: repeat(3, 1fr); }
  .case-grid.cols-4 { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 1400px) {
  .hero h1 { font-size: 58px; }
  .product-grid { gap: 24px; }
  .main-nav { gap: 22px; }
}

@media (max-width: 1280px) {
  .logo-cn { font-size: 28px; }
  .main-nav { gap: 18px; }
  .main-nav a { font-size: 14px; }
  .header-cta .phone-btn { font-size: 14px; }
}

@media (max-width: 1180px) {
  .site-header .container { gap: 16px; }
}

@media (max-width: 1024px) {
  html, body { font-size: 16px; }
  h1 { font-size: 44px; }
  h2 { font-size: 36px; }
  .hero h1 { font-size: 52px; }
  .page-hero h1 { font-size: 40px; }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .solution-grid, .case-grid, .case-grid.cols-4, .strength-grid { grid-template-columns: repeat(2, 1fr); }
  .process-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr 1fr; }
  .detail-layout { grid-template-columns: 1fr; }
  .detail-sidebar { position: static; }
}

@media (max-width: 768px) {
  html, body { font-size: 16px; }
  h1 { font-size: 34px; }
  h2 { font-size: 28px; }
  h3 { font-size: 22px; }
  .hero h1 { font-size: 38px; }
  .hero { min-height: 580px; }
  .hero-sub { font-size: 17px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 28px; }
  .hero-stat .num { font-size: 36px; }
  .page-hero { padding: 64px 0 48px; }
  .page-hero h1 { font-size: 30px; }
  .page-hero .sub { font-size: 16px; }

  section { padding: 72px 0; }
  .section-subtitle { font-size: 16px; margin-bottom: 40px; }
  .cta-banner { padding: 64px 0; }
  .cta-banner h2 { font-size: 26px; }
  .cta-banner p { font-size: 15px; }

  .site-header .container { height: 64px; gap: 16px; }
  .logo-cn { font-size: 22px; }
  .logo-en { display: none; }
  .main-nav { display: none; position: fixed; top: 64px; left: 0; right: 0; background: #fff;
    flex-direction: column; gap: 0; padding: 12px 0; border-top: 1px solid var(--color-border);
    box-shadow: var(--shadow-md); }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 16px 24px; font-size: 16px; border-bottom: 1px solid var(--color-bg-soft); }
  .main-nav a.active::after { display: none; }
  .header-cta { display: none; }
  .mobile-menu-btn { display: block; margin-left: auto; }

  .product-grid, .solution-grid, .case-grid, .case-grid.cols-4, .strength-grid, .guide-grid { grid-template-columns: 1fr; }
  .process-grid { grid-template-columns: repeat(2, 1fr); }
  .trust-row { grid-template-columns: repeat(2, 1fr); gap: 28px; }
  .trust-item .num { font-size: 40px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }

  /* 轮播图移动端样式 */
  .slider-btn { width: 36px; height: 36px; font-size: 16px; }
  .slider-btn.prev { left: 10px; }
  .slider-btn.next { right: 10px; }
  .slider-dots .dot { width: 8px; height: 8px; }
  .sound-toggle { width: 36px; height: 36px; font-size: 16px; bottom: 10px; right: 10px; }

  .form-row { grid-template-columns: 1fr; }
  .contact-form { padding: 28px; }

  .cta-banner .inner { flex-direction: column; align-items: flex-start; }
  .article-content h2 { font-size: 26px; }
  .article-content p, .article-content ul li { font-size: 16px; }

  .float-contact { display: none; }
  .mobile-cta-bar { display: flex; }
  body { padding-bottom: 60px; }

  .anchor-nav { margin: 0 -24px 32px; padding: 4px 24px; border-radius: 0; }
  .anchor-nav a { padding: 10px 18px; font-size: 14px; }
}

@media (max-width: 480px) {
  .container { padding: 0 20px; }
  .hero h1 { font-size: 32px; }
  .hero-stats .num { font-size: 32px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: span 2; }
}

/* ==========================================================================
   解决方案详情页专用样式
   ========================================================================== */

/* 详情页整体布局 */
.solution-detail { max-width: 1100px; margin: 0 auto; }

/* 方案概述区 */
.solution-intro { margin-bottom: 64px; }
.solution-intro h2 { font-size: 36px; margin-bottom: 24px; padding-bottom: 16px; border-bottom: 2px solid var(--color-border); }
.solution-intro > p { font-size: 18px; color: var(--color-text-light); margin-bottom: 32px; line-height: 1.85; }

/* 优势网格 */
.benefit-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; margin-top: 32px; }
.benefit-item {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  padding: 28px 24px; text-align: center; transition: var(--transition);
}
.benefit-item:hover { transform: translateY(-4px); border-color: var(--color-accent); box-shadow: var(--shadow-md); }
.benefit-icon { font-size: 42px; margin-bottom: 16px; display: block; }
.benefit-item h4 { font-size: 17px; margin-bottom: 10px; color: var(--color-primary); }
.benefit-item p { font-size: 14px; color: var(--color-text-light); line-height: 1.7; }

/* 配置表格 */
.solution-config { margin-bottom: 64px; }
.solution-config h2 { font-size: 36px; margin-bottom: 28px; padding-bottom: 16px; border-bottom: 2px solid var(--color-border); }
.config-table { width: 100%; border-collapse: collapse; margin: 24px 0; font-size: 15px; }
.config-table th, .config-table td { padding: 16px 18px; text-align: left; border-bottom: 1px solid var(--color-border); }
.config-table th {
  background: linear-gradient(135deg, #F5F5F5, #FAFAFA);
  font-weight: 700; color: var(--color-primary); width: 18%; font-size: 15px;
  border-top: 2px solid var(--color-border);
}
.config-table td { color: #444; line-height: 1.7; }
.config-table tr:hover td { background: var(--color-bg-soft); }
.config-table .note { font-size: 14px; color: var(--color-text-light); margin-top: 16px; font-style: italic; }

/* 案例区 */
.solution-cases { margin-bottom: 64px; }
.solution-cases h2 { font-size: 36px; margin-bottom: 28px; padding-bottom: 16px; border-bottom: 2px solid var(--color-border); }
.case-grid.cols-3 { grid-template-columns: repeat(3, 1fr); gap: 28px; }

/* FAQ 区 */
.solution-faq { margin-bottom: 64px; }
.solution-faq h2 { font-size: 36px; margin-bottom: 28px; padding-bottom: 16px; border-bottom: 2px solid var(--color-border); }
.solution-faq .faq-list { max-width: 100%; }
.solution-faq .faq-item {
  padding: 28px 32px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin-bottom: 16px;
  transition: var(--transition);
}
.solution-faq .faq-item:hover { border-color: var(--color-accent); box-shadow: var(--shadow-sm); }
.solution-faq .faq-item h4 {
  font-size: 18px; font-weight: 600; color: var(--color-primary);
  margin-bottom: 14px; display: flex; align-items: flex-start; gap: 12px;
}
.solution-faq .faq-item h4::before {
  content: 'Q'; flex-shrink: 0;
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 50%;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-dark)); color: #fff;
  font-size: 14px; font-weight: 700;
}
.solution-faq .faq-item p {
  font-size: 16px; color: var(--color-text-light); line-height: 1.85;
  padding-left: 44px; margin-top: 14px;
}
.solution-faq .faq-item:last-child { margin-bottom: 0; }

/* 流程区 */
.solution-process { margin-bottom: 48px; }
.solution-process h2 { font-size: 36px; margin-bottom: 36px; padding-bottom: 16px; border-bottom: 2px solid var(--color-border); text-align: center; }

/* 响应式 */
@media (max-width: 1024px) {
  .benefit-grid { grid-template-columns: repeat(2, 1fr); }
  .case-grid.cols-3 { grid-template-columns: repeat(2, 1fr); }
  .config-table { font-size: 14px; }
  .config-table th, .config-table td { padding: 14px 12px; }
}

@media (max-width: 768px) {
  .solution-intro h2, .solution-config h2, .solution-cases h2, .solution-faq h2, .solution-process h2 {
    font-size: 28px;
  }
  .benefit-grid { grid-template-columns: 1fr; }
  .case-grid.cols-3 { grid-template-columns: 1fr; }
  .config-table thead { display: none; }
  .config-table tr { display: block; margin-bottom: 16px; border: 1px solid var(--color-border); border-radius: var(--radius-lg); }
  .config-table td { display: block; padding: 12px 16px; border-bottom: 1px solid var(--color-bg-soft); }
  .config-table td::before { content: attr(data-label); font-weight: 700; color: var(--color-primary); display: block; margin-bottom: 4px; }
  .solution-faq .faq-item h4 { font-size: 16px; }
  .solution-faq .faq-item p { font-size: 15px; padding-left: 0; }
}

/* ==========================================================================
   资讯中心 - news.html 专用样式
   ========================================================================== */

/* 分类导航 */
.anchor-nav {
  display: flex; justify-content: center; gap: 12px; margin-bottom: 48px;
  flex-wrap: wrap;
}
.anchor-nav a {
  padding: 10px 20px; border: 1px solid var(--color-border); border-radius: 32px;
  font-size: 15px; color: var(--color-text-light); transition: var(--transition);
  cursor: pointer;
}
.anchor-nav a:hover { border-color: var(--color-accent); color: var(--color-accent); }
.anchor-nav a.active { background: var(--color-accent); border-color: var(--color-accent); color: #fff; }

/* 新闻分区 */
.news-section { margin-bottom: 64px; }
.section-title-with-icon {
  font-size: 28px; margin-bottom: 28px; padding-bottom: 12px;
  border-bottom: 2px solid var(--color-border); display: flex; align-items: center; gap: 12px;
}
.section-title-with-icon .icon { font-size: 32px; }

/* 新闻网格 */
.news-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.news-card {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  padding: 28px 24px; transition: var(--transition); display: flex; flex-direction: column; justify-content: space-between;
}
.news-card:hover {
  transform: translateY(-4px); border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}
.news-card .meta { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; font-size: 13px; }
.news-card .tag {
  display: inline-block; padding: 4px 10px; border-radius: 4px;
  background: var(--color-bg-soft); color: var(--color-text-light); font-size: 12px;
}
.news-card.guide .tag { background: #E8F4FD; color: #0066CC; }
.news-card.case .tag { background: #E8F8ED; color: #009955; }
.news-card.industry .tag { background: #FFF4E8; color: #FF6B1A; }
.news-card.faq .tag { background: #F0E8FF; color: #6B3BD6; }
.news-card .date { color: var(--color-text-mute); }
.news-card h3 { font-size: 18px; margin-bottom: 10px; line-height: 1.5; }
.news-card .desc { font-size: 15px; color: var(--color-text-light); line-height: 1.7; margin-bottom: 16px; }
.news-card .more { font-size: 14px; color: var(--color-accent); font-weight: 600; }

/* 占位卡片 */
.news-card.placeholder { opacity: 0.7; }
.news-card.placeholder .more { color: var(--color-text-mute); }

/* 列表式新闻（FAQ） */
.news-list { display: flex; flex-direction: column; gap: 12px; }
.news-list-item {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  padding: 20px 24px; transition: var(--transition); display: flex; flex-direction: column; gap: 8px;
}
.news-list-item:hover { border-color: var(--color-accent); box-shadow: var(--shadow-sm); }
.news-list-item .q { font-size: 16px; font-weight: 600; color: var(--color-primary); }
.news-list-item .a { font-size: 15px; color: var(--color-text-light); }

/* 响应式 */
@media (max-width: 1024px) {
  .news-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .news-grid { grid-template-columns: 1fr; }
  .section-title-with-icon { font-size: 24px; }
  .anchor-nav a { padding: 8px 16px; font-size: 14px; }
}