/* ==========================================================
   江苏同泽电子科技 · 微软代理商官网
   微软 Fluent 风格 / 响应式 / 无障碍友好
   ========================================================== */

:root {
  /* 微软品牌色 */
  --ms-blue: #0078d4;
  --ms-blue-dark: #0067b8;
  --ms-blue-light: #e6f2fb;
  --ms-green: #107c10;
  --ms-purple: #5c2d91;

  /* 中性色 */
  --ink: #1a1a1a;
  --ink-soft: #4b5563;
  --ink-mute: #6b7280;
  --bg: #ffffff;
  --bg-soft: #f5f7fa;
  --line: #e5e7eb;

  /* Copilot 深色区 */
  --dark-bg: #0b1020;
  --dark-card: #151b31;
  --dark-line: rgba(255, 255, 255, 0.09);

  /* 渐变 */
  --grad-ms: linear-gradient(120deg, #0067b8 0%, #0078d4 45%, #0f6bd6 100%);
  --grad-copilot: linear-gradient(120deg, #5c2d91 0%, #0078d4 100%);

  /* 布局 */
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 2px 10px rgba(16, 40, 70, 0.06);
  --shadow-md: 0 10px 30px rgba(16, 40, 70, 0.10);
  --shadow-lg: 0 24px 60px rgba(16, 40, 70, 0.16);
  --container: 1140px;
  --header-h: 68px;

  --font: "Segoe UI", "Microsoft YaHei", "PingFang SC", -apple-system, "Helvetica Neue", Arial, sans-serif;
}

/* ---------- Reset / 基础 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 12px); }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img, svg { display: inline-block; vertical-align: middle; }
a { color: var(--ms-blue); text-decoration: none; }
a:hover { text-decoration: none; }
ul, ol { list-style: none; }

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

/* 焦点可见（无障碍） */
a:focus-visible, button:focus-visible, input:focus-visible,
select:focus-visible, textarea:focus-visible {
  outline: 3px solid rgba(0, 120, 212, 0.45);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
  height: var(--header-h);
  display: flex;
  align-items: center;
}

.nav { display: flex; align-items: center; justify-content: space-between; gap: 16px; }

.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); }
.brand-logo { flex: none; border-radius: 6px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-text strong { font-size: 17px; font-weight: 700; letter-spacing: 0.2px; }
.brand-text small { font-size: 11.5px; color: var(--ink-mute); letter-spacing: 0.5px; }

.nav-menu { display: flex; align-items: center; gap: 6px; }

.nav-menu a {
  display: block;
  padding: 9px 14px;
  font-size: 15px;
  color: var(--ink-soft);
  border-radius: 8px;
  transition: background 0.2s, color 0.2s;
}
.nav-menu a:hover { background: var(--bg-soft); color: var(--ms-blue); }

.nav-cta {
  background: var(--grad-ms);
  color: #fff !important;
  font-weight: 600;
  margin-left: 8px;
  box-shadow: var(--shadow-sm);
}
.nav-cta:hover { background: var(--ms-blue-dark); color: #fff !important; }

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: none;
  border: none;
  cursor: pointer;
  border-radius: 8px;
}
.nav-toggle span {
  display: block;
  height: 2.5px;
  width: 100%;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- 通用区块 ---------- */
.section { padding: 88px 0; }
.section-alt { background: var(--bg-soft); }
.section-dark {
  background: var(--dark-bg);
  color: #fff;
  position: relative;
  overflow: hidden;
}
.section-dark::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(600px 320px at 12% 0%, rgba(92, 45, 145, 0.35), transparent 60%),
    radial-gradient(700px 380px at 90% 100%, rgba(0, 120, 212, 0.28), transparent 60%);
  pointer-events: none;
}
.section-dark .container { position: relative; }

.section-head { text-align: center; max-width: 720px; margin: 0 auto 52px; }

.eyebrow {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 2.5px;
  color: var(--ms-blue);
  margin-bottom: 12px;
  text-transform: uppercase;
}
.section-dark .eyebrow { color: #7ec8f5; }

.section-head h2 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.5px;
}
.section-head .lead {
  margin-top: 16px;
  font-size: 17px;
  color: var(--ink-soft);
}
.section-dark .section-head .lead { color: rgba(255, 255, 255, 0.72); }

.grid {
  display: grid;
  gap: 24px;
}

/* 卡片 */
.card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 120, 212, 0.35);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid transparent;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s, color 0.2s;
  white-space: nowrap;
}
.btn-primary { background: var(--grad-ms); color: #fff; box-shadow: 0 6px 18px rgba(0, 103, 184, 0.3); }
.btn-primary:hover { background: var(--ms-blue-dark); transform: translateY(-2px); }
.btn-ghost {
  background: transparent;
  color: var(--ms-blue-dark);
  border-color: rgba(0, 103, 184, 0.4);
}
.btn-ghost:hover { background: var(--ms-blue-light); transform: translateY(-2px); }
.btn-light { background: #fff; color: var(--dark-bg); }
.btn-light:hover { background: #e8eef7; transform: translateY(-2px); }
.btn-block { width: 100%; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  background: linear-gradient(180deg, #f0f7fe 0%, #ffffff 70%);
  padding: 76px 0 0;
  overflow: hidden;
}

.hero-bg { position: absolute; inset: 0; pointer-events: none; }
.blob { position: absolute; border-radius: 50%; filter: blur(60px); opacity: 0.55; }
.blob-1 { width: 460px; height: 460px; background: rgba(0, 120, 212, 0.18); top: -140px; left: -120px; }
.blob-2 { width: 380px; height: 380px; background: rgba(124, 58, 237, 0.14); top: 60px; right: -100px; }
.blob-3 { width: 320px; height: 320px; background: rgba(0, 168, 239, 0.14); bottom: -120px; left: 35%; }

.hero-inner {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 56px;
  align-items: center;
  position: relative;
}

.hero-eyebrow {
  display: inline-block;
  background: var(--ms-blue-light);
  color: var(--ms-blue-dark);
  font-size: 14px;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: 100px;
  margin-bottom: 22px;
}

.hero h1 {
  font-size: clamp(32px, 4.6vw, 50px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -1px;
}
.grad-text {
  background: var(--grad-copilot);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  margin-top: 20px;
  font-size: 18px;
  color: var(--ink-soft);
  max-width: 560px;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 30px; }

.hero-tip { margin-top: 20px; font-size: 15px; color: var(--ink-mute); }
.hero-tip a { color: var(--ms-blue-dark); font-weight: 600; }

/* Hero 右侧视觉卡片 */
.hero-visual { position: relative; min-height: 380px; }

.visual-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 20px 22px;
  position: absolute;
}
.card-main {
  top: 20px;
  left: 6%;
  right: 6%;
  z-index: 2;
  animation: floatY 6s ease-in-out infinite;
}
.card-float-1 {
  bottom: 26px;
  left: 0;
  width: 44%;
  z-index: 3;
  animation: floatY 7s ease-in-out 0.8s infinite;
}
.card-float-2 {
  bottom: 60px;
  right: 0;
  width: 42%;
  z-index: 1;
  animation: floatY 6.5s ease-in-out 1.6s infinite;
}

@keyframes floatY {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.vc-head { display: flex; align-items: center; gap: 12px; }
.vc-head strong { font-size: 17px; display: block; line-height: 1.2; }
.vc-head small { font-size: 12px; color: var(--ink-mute); }

.vc-ico {
  width: 46px;
  height: 46px;
  flex: none;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 800;
  color: #fff;
  font-family: "Segoe UI", Arial, sans-serif;
}

.ico-w { background: linear-gradient(135deg, #185abd, #2b7cd3); }
.ico-x { background: linear-gradient(135deg, #107c10, #34a853); }
.ico-p { background: linear-gradient(135deg, #d24726, #f15a24); }
.ico-o { background: linear-gradient(135deg, #0a5fa3, #0078d4); }
.ico-t { background: linear-gradient(135deg, #4b53bc, #7b83eb); }
.ico-d { background: linear-gradient(135deg, #0364b8, #12a0e6); font-size: 20px; }

.vc-lines { margin-top: 16px; display: flex; flex-direction: column; gap: 9px; }
.vc-lines span {
  display: block;
  height: 9px;
  border-radius: 6px;
  background: linear-gradient(90deg, var(--ms-blue-light), #ddeeff);
}
.vc-lines span:nth-child(2) { opacity: 0.8; }
.vc-lines span:nth-child(3) { opacity: 0.6; }
.vc-lines span:nth-child(4) { opacity: 0.45; }

.vc-ai-tag {
  margin-top: 16px;
  background: linear-gradient(120deg, rgba(92, 45, 145, 0.08), rgba(0, 120, 212, 0.08));
  border: 1px dashed rgba(92, 45, 145, 0.35);
  color: var(--ms-purple);
  font-size: 13px;
  font-weight: 600;
  padding: 8px 12px;
  border-radius: 8px;
}

/* 信任数据条 */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 56px;
  padding-top: 36px;
  padding-bottom: 44px;
  border-top: 1px solid var(--line);
}
.stat { text-align: center; }
.stat strong {
  display: block;
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 800;
  color: var(--ms-blue-dark);
  line-height: 1.2;
}
.stat span { font-size: 14px; color: var(--ink-mute); }

/* ---------- 产品区 ---------- */
.products-grid { grid-template-columns: repeat(3, 1fr); }

.product-card { text-align: left; }
.p-ico {
  width: 52px;
  height: 52px;
  border-radius: 13px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  font-weight: 800;
  color: #fff;
  margin-bottom: 18px;
  font-family: "Segoe UI", Arial, sans-serif;
}
.product-card h3 { font-size: 19px; margin-bottom: 10px; font-weight: 700; }
.product-card p { font-size: 15px; color: var(--ink-soft); }

.banner-inline {
  margin-top: 40px;
  background: var(--grad-ms);
  color: #fff;
  border-radius: var(--radius);
  padding: 34px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  box-shadow: var(--shadow-md);
  flex-wrap: wrap;
}
.banner-inline h3 { font-size: 22px; margin-bottom: 6px; }
.banner-inline p { opacity: 0.92; font-size: 15.5px; max-width: 640px; }
.banner-inline .btn {
  background: #fff;
  color: var(--ms-blue-dark);
}
.banner-inline .btn:hover { background: var(--ms-blue-light); }

/* ---------- Copilot 专区 ---------- */
.copilot-grid { grid-template-columns: repeat(3, 1fr); }

.copilot-card {
  background: var(--dark-card);
  border: 1px solid var(--dark-line);
  color: #fff;
}
.copilot-card:hover { border-color: rgba(126, 200, 245, 0.4); }

.c-ico {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(92, 45, 145, 0.55), rgba(0, 120, 212, 0.55));
  border: 1px solid rgba(255, 255, 255, 0.12);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  margin-bottom: 16px;
}
.copilot-card h3 { font-size: 18px; margin-bottom: 8px; }
.copilot-card p { font-size: 14.5px; color: rgba(255, 255, 255, 0.68); }

.copilot-cta {
  margin-top: 44px;
  background: linear-gradient(120deg, rgba(92, 45, 145, 0.35), rgba(0, 120, 212, 0.30));
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  padding: 34px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}
.copilot-cta h3 { font-size: 22px; margin-bottom: 6px; }
.copilot-cta p { font-size: 15.5px; color: rgba(255, 255, 255, 0.75); }

/* ---------- 为什么选择我们 ---------- */
.why-grid { grid-template-columns: repeat(3, 1fr); }
.why-card { position: relative; padding-top: 36px; }
.w-num {
  position: absolute;
  top: 20px;
  right: 24px;
  font-size: 40px;
  font-weight: 800;
  color: rgba(0, 120, 212, 0.10);
  line-height: 1;
  font-family: "Segoe UI", Arial, sans-serif;
}
.why-card h3 { font-size: 18.5px; margin-bottom: 10px; }
.why-card p { font-size: 15px; color: var(--ink-soft); }

/* ---------- 服务流程 ---------- */
.process-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0;
  counter-reset: step;
}
.process-step {
  display: flex;
  gap: 24px;
  padding: 26px 0;
  position: relative;
}
.process-step:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 27px;
  top: 74px;
  bottom: -6px;
  width: 2px;
  background: linear-gradient(180deg, var(--ms-blue), rgba(0, 120, 212, 0.15));
}
.step-num {
  flex: none;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--grad-ms);
  color: #fff;
  font-size: 22px;
  font-weight: 800;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 16px rgba(0, 103, 184, 0.28);
  font-family: "Segoe UI", Arial, sans-serif;
}
.process-step h3 { font-size: 19px; margin-bottom: 6px; }
.process-step p { font-size: 15.5px; color: var(--ink-soft); }

/* ---------- 联系区 ---------- */
.contact-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
}
.contact-info h2 { font-size: clamp(26px, 3.4vw, 36px); font-weight: 800; line-height: 1.3; }
.contact-info .lead { color: var(--ink-soft); margin: 14px 0 30px; font-size: 16.5px; }

.contact-list { display: flex; flex-direction: column; gap: 20px; }
.contact-list li { display: flex; flex-direction: column; gap: 2px; }
.c-label {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--ink-mute);
  text-transform: uppercase;
}
.contact-list a { font-size: 19px; font-weight: 700; color: var(--ink); }
.contact-list a:hover { color: var(--ms-blue); }
.contact-list li > span:last-child { font-size: 16px; }
.contact-list small { font-size: 13px; color: var(--ink-mute); }

.contact-form { padding: 36px; }
.contact-form h3 { font-size: 22px; margin-bottom: 22px; }
.form-row { margin-bottom: 18px; }
.form-row label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 7px;
}
.req { color: #d13438; }
.form-row input,
.form-row select,
.form-row textarea {
  width: 100%;
  padding: 12px 14px;
  font-size: 15px;
  font-family: inherit;
  color: var(--ink);
  background: var(--bg-soft);
  border: 1.5px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
}
.form-row input:focus,
.form-row select:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--ms-blue);
  background: #fff;
  box-shadow: 0 0 0 4px rgba(0, 120, 212, 0.12);
}
.form-row input.invalid,
.form-row select.invalid {
  border-color: #d13438;
  box-shadow: 0 0 0 4px rgba(209, 52, 56, 0.10);
}
.form-note { margin-top: 14px; font-size: 14px; text-align: center; }
.form-note.ok { color: var(--ms-green); }
.form-note.err { color: #d13438; }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--dark-bg); color: rgba(255, 255, 255, 0.7); }
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding-top: 36px;
  padding-bottom: 36px;
  flex-wrap: wrap;
}
.footer-brand { display: flex; align-items: center; gap: 10px; color: #fff; }
.footer-desc { margin-top: 10px; font-size: 14px; color: rgba(255, 255, 255, 0.55); }
.footer-meta { text-align: right; font-size: 13.5px; line-height: 1.9; color: rgba(255, 255, 255, 0.5); }

/* ---------- 滚动渐显动画 ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .card-main, .card-float-1, .card-float-2 { animation: none; }
}

/* ==========================================================
   响应式断点
   ========================================================== */

/* 平板 */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { min-height: 300px; max-width: 560px; margin: 0 auto; width: 100%; }
  .products-grid, .copilot-grid, .why-grid { grid-template-columns: repeat(2, 1fr); }
}

/* 手机 */
@media (max-width: 768px) {
  :root { --header-h: 60px; }
  .section { padding: 64px 0; }
  .container { padding: 0 18px; }

  /* 导航折叠为抽屉 */
  .nav-toggle { display: flex; }
  .nav-menu {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-md);
    padding: 12px 18px 18px;
    gap: 4px;
    transform: translateY(-16px);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.25s ease, opacity 0.25s ease, visibility 0.25s;
    z-index: 99;
  }
  .nav-menu.open { transform: none; opacity: 1; visibility: visible; }
  .nav-menu a { padding: 13px 14px; font-size: 16px; }
  .nav-cta { margin: 8px 0 0; text-align: center; }

  .brand-text strong { font-size: 15.5px; }
  .brand-text small { font-size: 10.5px; }

  /* Hero */
  .hero { padding: 52px 0 0; }
  .hero h1 { font-size: 30px; }
  .hero-sub { font-size: 16px; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 28px 16px; }

  /* 卡片 */
  .products-grid, .copilot-grid, .why-grid { grid-template-columns: 1fr; }
  .card { padding: 22px; }

  .banner-inline, .copilot-cta { padding: 26px 24px; flex-direction: column; align-items: flex-start; }
  .banner-inline .btn, .copilot-cta .btn { width: 100%; }

  /* 流程 */
  .process-step { gap: 16px; padding: 20px 0; }

  /* 联系 */
  .contact-wrap { grid-template-columns: 1fr; gap: 40px; }
  .contact-form { padding: 26px 22px; }

  .footer-inner { flex-direction: column; align-items: flex-start; text-align: left; }
  .footer-meta { text-align: left; }
}

/* 小屏手机 */
@media (max-width: 420px) {
  .hero-visual { min-height: 260px; }
  .visual-card { padding: 16px; }
  .vc-ico { width: 40px; height: 40px; font-size: 20px; }
}

/* ---------- FAQ 常见问题（details 原生折叠，无 JS 依赖，爬虫可读） ---------- */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.faq-item:hover { border-color: rgba(0, 120, 212, 0.35); }
.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 22px;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--ink);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  flex: none;
  font-size: 24px;
  font-weight: 400;
  line-height: 1;
  color: var(--ms-blue);
  transition: transform 0.2s;
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item[open] { box-shadow: var(--shadow-sm); border-color: rgba(0, 120, 212, 0.35); }
.faq-body {
  padding: 0 22px 18px;
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
}
.faq-item summary:focus-visible { outline: 3px solid rgba(0, 120, 212, 0.45); outline-offset: -3px; }