/* ============================================================
   西科索尔官网 · 设计系统 v2
   配色：深青绿(emerald/teal) + 深石板灰，非蓝、企业级科技感
   纯 CSS，无外部依赖
   ============================================================ */

:root {
  /* 品牌色 */
  --brand-900: #042f2e;
  --brand-800: #064e46;
  --brand-700: #0f766e;
  --brand-600: #0d9488;
  --brand-500: #14b8a6;
  --brand-400: #2dd4bf;
  --brand-300: #5eead4;
  --brand-100: #ccfbf1;
  --brand-50:  #f0fdfa;

  /* 中性色 */
  --ink-900: #0f172a;
  --ink-800: #1e293b;
  --ink-700: #334155;
  --ink-600: #475569;
  --ink-500: #64748b;
  --ink-400: #94a3b8;
  --line:    #e2e8f0;
  --bg:      #ffffff;
  --bg-soft: #f8fafc;
  --bg-tint: #f0fdfa;

  /* 排版 */
  --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --maxw: 1200px;

  /* 圆角 / 阴影 */
  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 16px;
  --r-xl: 22px;
  --r-full: 999px;
  --shadow-sm: 0 1px 2px rgba(15,23,42,.06), 0 1px 3px rgba(15,23,42,.08);
  --shadow-md: 0 12px 28px -8px rgba(15,23,42,.12), 0 6px 12px -6px rgba(15,23,42,.06);
  --shadow-lg: 0 25px 50px -12px rgba(15,23,42,.18);
  --shadow-brand: 0 20px 45px -15px rgba(13,148,136,.45);

  /* 动效 */
  --ease: cubic-bezier(.22,.61,.36,1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--ink-800);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { color: var(--ink-900); line-height: 1.25; font-weight: 700; letter-spacing: -.01em; margin: 0 0 .5em; }
h1 { font-size: clamp(2rem, 5vw, 3.4rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); }
h3 { font-size: 1.25rem; }
p { margin: 0 0 1rem; }
section { padding: clamp(3.5rem, 8vw, 6.5rem) 0; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 26px; border-radius: var(--r-full);
  font-weight: 600; font-size: 15px; cursor: pointer;
  border: 1px solid transparent; transition: all .25s var(--ease);
  white-space: nowrap;
}
.btn-primary { background: var(--brand-600); color: #fff; box-shadow: var(--shadow-brand); }
.btn-primary:hover { background: var(--brand-700); transform: translateY(-2px); }
.btn-ghost { background: rgba(255,255,255,.08); color: #fff; border-color: rgba(255,255,255,.25); }
.btn-ghost:hover { background: rgba(255,255,255,.16); }
.btn-outline { background: transparent; color: var(--brand-700); border-color: var(--brand-600); }
.btn-outline:hover { background: var(--brand-50); transform: translateY(-2px); }
.btn-dark { background: var(--ink-900); color: #fff; }
.btn-dark:hover { background: var(--ink-800); transform: translateY(-2px); }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.86);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink-900); }
.brand .logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--brand-500), var(--brand-800));
  display: grid; place-items: center; color: #fff; font-weight: 800; font-size: 15px;
  box-shadow: var(--shadow-brand);
}
.brand .logo-img {
  height: 46px; width: auto; display: block;
}
.nav-links { display: flex; align-items: center; gap: 30px; list-style: none; margin: 0; padding: 0; }
.nav-links a { color: var(--ink-700); font-weight: 500; font-size: 15px; transition: color .2s; }
.nav-links a:hover, .nav-links a.active { color: var(--brand-700); }
.nav-cta { display: flex; align-items: center; gap: 14px; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--ink-800); margin: 4px 0; transition: .3s; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(1100px 500px at 80% -10%, rgba(45,212,191,.32), transparent 60%),
    radial-gradient(900px 600px at 0% 10%, rgba(13,148,136,.26), transparent 55%),
    linear-gradient(160deg, var(--brand-900), #073b39 55%, #062f2c);
  color: #fff;
  padding: clamp(4.5rem, 10vw, 8rem) 0 clamp(4rem, 9vw, 7rem);
}
.hero::after {
  content: ""; position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size: 46px 46px; mask-image: radial-gradient(circle at 70% 30%, #000, transparent 75%);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 1; }
.hero-tag {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border-radius: var(--r-full);
  background: rgba(255,255,255,.10); border: 1px solid rgba(255,255,255,.18);
  font-size: 13px; color: var(--brand-300); margin-bottom: 22px; font-weight: 500;
}
.hero h1 { color: #fff; max-width: 18ch; }
.hero p.lead { color: rgba(255,255,255,.82); font-size: clamp(1.05rem, 2vw, 1.25rem); max-width: 56ch; margin: 18px 0 30px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-stats { display: flex; flex-wrap: wrap; gap: 48px; margin-top: 56px; }
.hero-stats .stat .num { font-size: clamp(1.8rem, 4vw, 2.4rem); font-weight: 800; color: #fff; line-height: 1; }
.hero-stats .stat .lbl { font-size: 14px; color: rgba(255,255,255,.72); margin-top: 6px; }

/* ---------- 通用区块 ---------- */
.section-head { max-width: 760px; margin: 0 auto 3rem; text-align: center; }
.section-head .eyebrow { color: var(--brand-600); font-weight: 700; letter-spacing: .12em; text-transform: uppercase; font-size: 13px; }
.section-head p { color: var(--ink-500); font-size: 1.05rem; }
.bg-soft { background: var(--bg-soft); }
.bg-tint { background: var(--bg-tint); }

/* ---------- 卡片网格 ---------- */
.grid { display: grid; gap: 26px; }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r-lg);
  padding: 30px; transition: transform .35s var(--ease), box-shadow .35s var(--ease), border-color .35s;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: transparent; }

/* ---------- 动态 SVG 图标（itshover 风格：24×24、2px 描边、悬停动画） ---------- */
.card .ic,
.feature .ic {
  width: 50px; height: 50px; border-radius: 13px; display: grid; place-items: center;
  background: var(--brand-600); color: #fff; margin-bottom: 18px;
  transition: background .3s var(--ease), transform .3s var(--ease);
  box-shadow: 0 8px 20px -6px rgba(13,148,136,.35);
}
.card .ic svg,
.feature .ic svg { width: 26px; height: 26px; stroke: currentColor; stroke-width: 1.7; fill: none; stroke-linecap: round; stroke-linejoin: round; transition: transform .35s var(--ease); }
.card:hover .ic,
.feature:hover .ic { background: var(--brand-700); transform: scale(1.04); }
.card:hover .ic svg,
.feature:hover .ic svg { transform: scale(1.1); }
/* 描边依次绘制动画 */
.ic svg .draw { stroke-dasharray: 80; }
.card:hover .ic svg .draw,
.feature:hover .ic svg .draw { animation: draw-in .6s var(--ease) forwards; }
@keyframes draw-in { from { stroke-dashoffset: 80; } to { stroke-dashoffset: 0; } }
@media (prefers-reduced-motion: reduce) {
  .ic svg .draw { animation: none !important; }
  .card:hover .ic svg, .feature:hover .ic svg { transform: none; }
}
.card h3 { margin-bottom: 8px; }
.card p { color: var(--ink-500); margin: 0; font-size: 15px; }

/* 特性列表 */
.feature { display: flex; gap: 16px; align-items: flex-start; }
.feature .ic { flex: 0 0 auto; margin-bottom: 0; }
.feature h3 { font-size: 1.1rem; }
.feature p { font-size: 15px; color: var(--ink-500); }

/* ---------- 数据统计条 ---------- */
.stats-band {
  background: linear-gradient(135deg, var(--brand-900), var(--brand-700));
  color: #fff; border-radius: var(--r-md); padding: clamp(2rem, 5vw, 3rem);
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; text-align: center;
  box-shadow: var(--shadow-md);
}
.stats-band .num { font-size: clamp(1.8rem, 4vw, 2.6rem); font-weight: 800; }
.stats-band .lbl { color: rgba(255,255,255,.78); font-size: 14px; margin-top: 4px; }

/* ---------- 案例卡片 ---------- */
.case-card {
  overflow: hidden; padding: 0; border-radius: var(--r-md);
  display: flex; flex-direction: column;
  background: var(--bg);
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), border-color .35s;
}
.case-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px -12px rgba(15,23,42,.12);
  border-color: transparent;
}
.case-card .thumb {
  height: 150px;
  background:
    radial-gradient(circle at 20% 0%, rgba(45,212,191,.22), transparent 50%),
    linear-gradient(145deg, var(--ink-800) 0%, var(--brand-900) 100%);
  position: relative; overflow: hidden;
  display: grid; place-items: center;
}
.case-card .thumb svg {
  width: 42px; height: 42px; stroke: #fff; stroke-width: 1.6; fill: none;
  stroke-linecap: round; stroke-linejoin: round;
  opacity: .9; transform: translateY(0); transition: transform .45s var(--ease), opacity .35s;
}
.case-card .thumb::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(45,212,191,0) 55%, rgba(45,212,191,.10) 100%);
  opacity: 0; transition: opacity .4s;
}
.case-card:hover .thumb svg { transform: translateY(-4px) scale(1.05); opacity: 1; }
.case-card:hover .thumb::after { opacity: 1; }
.case-card .body { padding: 22px 24px 26px; flex: 1; display: flex; flex-direction: column; }
.case-card .tag {
  font-size: 12px; color: var(--brand-700); font-weight: 700; letter-spacing: .06em;
  display: inline-flex; align-self: flex-start;
  padding: 4px 10px; border-radius: var(--r-full); background: var(--brand-50); margin-bottom: 10px;
}
.case-card h3 { margin: 0 0 10px; font-size: 1.12rem; }
.case-card p { color: var(--ink-500); font-size: 14px; margin: 0; line-height: 1.65; }
.case-card .meta {
  margin-top: auto; padding-top: 16px; font-size: 13px; color: var(--brand-600); font-weight: 600;
  border-top: 1px solid var(--line); margin-top: 18px; display: inline-flex; align-items: center; gap: 6px;
}
.case-card .meta::after {
  content: "→"; transition: transform .25s var(--ease);
}
.case-card:hover .meta::after { transform: translateX(4px); }

/* ---------- 客户 Logo 墙 ---------- */
.logo-wall { display: flex; flex-wrap: wrap; gap: 18px; justify-content: center; align-items: center; }
.logo-wall .logo-item {
  height: 64px; min-width: 150px; padding: 0 24px; border: 1px solid var(--line); border-radius: var(--r-md);
  display: grid; place-items: center; color: var(--ink-500); font-weight: 600; background: var(--bg);
  font-size: 14px; transition: all .25s var(--ease);
}
.logo-wall .logo-item:hover { border-color: var(--brand-400); color: var(--brand-700); box-shadow: var(--shadow-sm); }

/* ---------- CTA ---------- */
.cta {
  background: linear-gradient(135deg, var(--brand-900), var(--brand-700));
  color: #fff; border-radius: var(--r-lg); padding: clamp(2.5rem,6vw,4rem); text-align: center; position: relative; overflow: hidden;
}
.cta h2 { color: #fff; }
.cta p { color: rgba(255,255,255,.82); max-width: 56ch; margin: 0 auto 26px; }
.cta::before { content:""; position:absolute; width: 420px; height: 420px; border-radius: 50%; background: rgba(45,212,191,.22); filter: blur(24px); top:-140px; right:-100px; }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--ink-900); color: #cbd5e1; padding: 56px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 36px; }
.site-footer .brand { color: #fff; margin-bottom: 14px; }
.site-footer .brand + p { color: #94a3b8; font-size: 13px; line-height: 1.5; max-width: 340px; margin-bottom: 0; }
.footer-col h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.footer-col a { display: block; color: #94a3b8; font-size: 14px; padding: 5px 0; transition: color .2s; }
.footer-col a:hover { color: var(--brand-300); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); margin-top: 36px; padding-top: 20px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px; color: #64748b; }
.footer-bottom a.icp-link { color: #94a3b8; text-decoration: none; transition: color .2s; }
.footer-bottom a.icp-link:hover { color: var(--brand-300); text-decoration: underline; }

/* ---------- 表单 ---------- */
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { display: flex; flex-direction: column; gap: 7px; }
.field.full { grid-column: 1 / -1; }
.field label { font-size: 14px; font-weight: 600; color: var(--ink-700); }
.field input, .field textarea, .field select {
  padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--r-sm);
  font-size: 15px; font-family: inherit; color: var(--ink-800); background: #fff; transition: border-color .2s, box-shadow .2s;
}
.field input:focus, .field textarea:focus, .field select:focus {
  outline: none; border-color: var(--brand-500); box-shadow: 0 0 0 3px rgba(20,184,166,.15);
}
.field textarea { min-height: 130px; resize: vertical; }
.captcha-row { display: flex; gap: 10px; align-items: stretch; }
.captcha-row input { flex: 1 1 auto; min-width: 0; }
.captcha-img {
  height: 48px; width: 132px; flex: 0 0 132px; object-fit: cover;
  border: 1px solid var(--line); border-radius: var(--r-sm); background: #fff;
  cursor: pointer; transition: border-color .2s, box-shadow .2s, opacity .2s;
}
.captcha-img:hover { border-color: var(--brand-500); box-shadow: 0 0 0 3px rgba(20,184,166,.12); }

/* ---------- 面包屑 / 内页头 ---------- */
.page-hero { background: var(--bg-tint); border-bottom: 1px solid var(--line); padding: clamp(3rem,7vw,4.5rem) 0; }
.page-hero .eyebrow { color: var(--brand-600); font-weight: 700; letter-spacing: .12em; text-transform: uppercase; font-size: 13px; }
.page-hero p { color: var(--ink-500); max-width: 60ch; }

/* ---------- 滚动揭示动画 ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- 技术栈 ---------- */
.tech-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.tech-card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r-md);
  padding: 22px 24px; transition: all .25s var(--ease);
}
.tech-card:hover { border-color: var(--brand-400); box-shadow: var(--shadow-sm); }
.tech-card h4 { font-size: 15px; color: var(--brand-700); margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
.tech-card p { margin: 0; color: var(--ink-600); font-size: 14px; line-height: 1.7; }

/* ---------- 时间线/历程 ---------- */
.timeline { position: relative; padding-left: 24px; }
.timeline::before { content: ""; position: absolute; left: 6px; top: 8px; bottom: 8px; width: 2px; background: var(--line); }
.timeline-item { position: relative; padding-bottom: 24px; }
.timeline-item::before { content: ""; position: absolute; left: -22px; top: 6px; width: 10px; height: 10px; border-radius: 50%; background: var(--brand-500); border: 2px solid #fff; box-shadow: 0 0 0 1px var(--brand-200); }
.timeline-item h4 { font-size: 16px; margin-bottom: 4px; }
.timeline-item p { margin: 0; color: var(--ink-500); font-size: 14px; }

/* ---------- 标签云 ---------- */
.tag-cloud { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-cloud span {
  padding: 7px 15px; border-radius: var(--r-full); background: var(--bg-soft);
  border: 1px solid var(--line); color: var(--ink-600); font-size: 13px; font-weight: 500;
  transition: all .25s var(--ease);
}
.tag-cloud span:hover {
  background: var(--brand-600); border-color: var(--brand-600); color: #fff;
  transform: translateY(-2px); box-shadow: 0 6px 14px -4px rgba(13,148,136,.3);
}

/* 深色卡片中的标签云 */
.tag-cloud-dark { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-cloud-dark span {
  padding: 8px 16px; border-radius: var(--r-full);
  background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.12);
  color: rgba(255,255,255,.85); font-size: 13px; font-weight: 500;
  transition: all .25s var(--ease);
  cursor: default;
}
.tag-cloud-dark span:hover {
  background: rgba(255,255,255,.16); border-color: rgba(255,255,255,.22);
  transform: translateY(-2px);
}

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .stats-band { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 760px) {
  .nav-links, .nav-cta .btn-outline { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex; flex-direction: column; gap: 4px;
    position: absolute; top: 68px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line); padding: 14px 24px 22px;
    box-shadow: var(--shadow-md);
  }
  .nav-links.open a { padding: 10px 0; }
  .grid-4, .grid-3, .grid-2, .form-grid, .tech-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 26px; }
  .stats-band { grid-template-columns: 1fr 1fr; gap: 22px; }
  .hero-stats { gap: 26px; }
}