/* ============================================================
   TelSec Web应用防火墙 - 官网样式
   ============================================================ */
:root {
  --bg: #0b1220;
  --bg-alt: #0f1a2e;
  --card: #131f38;
  --card-dark: #101a30;
  --line: rgba(148, 187, 255, 0.14);
  --text: #e6edf7;
  --text-dim: #9fb0c8;
  --brand: #103a8a;
  --accent: #22d3ee;
  --accent-2: #3b82f6;
  --grad: linear-gradient(120deg, #22d3ee, #3b82f6 60%, #8b5cf6);
  --radius: 14px;
  --shadow: 0 18px 44px rgba(2, 8, 24, 0.55);
  --font: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; }

.container { width: min(1160px, 92%); margin: 0 auto; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(11, 18, 32, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s, background .3s;
}
.site-header.scrolled { border-bottom-color: var(--line); background: rgba(9, 14, 26, 0.94); }

.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: 68px; }

.brand { display: flex; align-items: center; gap: 10px; }
.brand-icon { width: 34px; height: 34px; }
.brand-name { font-size: 19px; font-weight: 700; letter-spacing: .5px; color: #fff; display: flex; flex-direction: column; line-height: 1.15; }
.brand-sub { font-size: 11px; font-weight: 400; color: var(--text-dim); letter-spacing: 1px; }

.main-nav { display: flex; align-items: center; gap: 30px; }
.main-nav a { font-size: 14.5px; color: var(--text-dim); transition: color .25s; }
.main-nav a:hover { color: var(--accent); }
.main-nav .nav-cta {
  color: #04121f;
  background: var(--grad);
  padding: 8px 18px;
  border-radius: 8px;
  font-weight: 600;
}
.main-nav .nav-cta:hover { color: #04121f; filter: brightness(1.12); }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: #dbe6f5; margin: 5px 0; border-radius: 2px; transition: transform .25s, opacity .25s; }
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 0 80px;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(900px 480px at 78% -10%, rgba(59, 130, 246, 0.22), transparent 60%),
    radial-gradient(720px 420px at 12% 110%, rgba(34, 211, 238, 0.14), transparent 60%),
    linear-gradient(180deg, #0d1526 0%, #0b1220 100%);
}
.hero-bg::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(148, 187, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 187, 255, 0.06) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 40%, #000 30%, transparent 75%);
}
.hero-inner { position: relative; text-align: center; }

.hero-tag {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--accent);
  border: 1px solid rgba(34, 211, 238, 0.35);
  padding: 6px 16px;
  border-radius: 999px;
  margin-bottom: 26px;
  background: rgba(34, 211, 238, 0.07);
}
.hero-title { font-size: clamp(30px, 5vw, 52px); font-weight: 800; line-height: 1.28; letter-spacing: 1px; }
.hero-title .grad-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-desc { max-width: 720px; margin: 24px auto 0; color: var(--text-dim); font-size: 16px; }

.hero-actions { margin-top: 36px; display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 13px 30px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  transition: transform .2s, box-shadow .2s, background .2s;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--grad); color: #04121f; box-shadow: 0 10px 30px rgba(34, 211, 238, 0.25); }
.btn-primary:hover { box-shadow: 0 14px 36px rgba(34, 211, 238, 0.38); }
.btn-ghost { border: 1px solid rgba(148, 187, 255, 0.35); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

.hero-stats {
  margin-top: 68px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 860px;
  margin-left: auto; margin-right: auto;
}
.stat {
  background: rgba(19, 31, 56, 0.66);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 12px;
  backdrop-filter: blur(6px);
}
.stat-num { font-size: 30px; font-weight: 800; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; font-variant-numeric: tabular-nums; }
.stat-label { margin-top: 6px; font-size: 13px; color: var(--text-dim); }

/* ---------- 通用 section ---------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }

.section-head { text-align: center; margin-bottom: 56px; }
.section-head h2 { font-size: clamp(26px, 3.6vw, 36px); font-weight: 800; letter-spacing: .5px; }
.section-head h2::after {
  content: "";
  display: block;
  width: 52px; height: 4px;
  margin: 16px auto 0;
  border-radius: 2px;
  background: var(--grad);
}
.section-head p { margin-top: 14px; color: var(--text-dim); font-size: 15px; }

.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  transition: transform .28s, border-color .28s, box-shadow .28s;
}
.card:hover { transform: translateY(-6px); border-color: rgba(34, 211, 238, 0.45); box-shadow: var(--shadow); }
.card h3 { font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.card p { font-size: 14px; color: var(--text-dim); }

.card-icon {
  width: 46px; height: 46px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  color: var(--accent);
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.28);
  border-radius: 12px;
  margin-bottom: 16px;
}

.card-dark { background: var(--card-dark); }

/* ---------- 接入方式 steps ---------- */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.step {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 28px;
  position: relative;
  transition: transform .28s, border-color .28s;
}
.step:hover { transform: translateY(-6px); border-color: rgba(34, 211, 238, 0.45); }
.step-no {
  font-size: 40px;
  font-weight: 800;
  line-height: 1;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  opacity: .9;
  margin-bottom: 18px;
}
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--text-dim); }

/* ---------- 应用场景 ---------- */
.scenario {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  border-left: 4px solid var(--accent-2);
  display: flex;
  gap: 20px;
  align-items: flex-start;
  transition: transform .28s, border-color .28s;
}
.scenario:hover { transform: translateY(-5px); border-color: rgba(34, 211, 238, 0.45); }
.scenario-icon {
  flex: 0 0 auto;
  width: 52px; height: 52px;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px;
  color: var(--accent);
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.28);
  border-radius: 12px;
}
.scenario-title { font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.scenario p { font-size: 14px; color: var(--text-dim); }

/* ---------- 关于我们 ---------- */
.about-body { color: var(--text-dim); font-size: 15.5px; display: grid; gap: 18px; }

/* ---------- 联系我们 ---------- */
.contact-item {
  text-align: center;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 34px 20px;
  transition: transform .28s, border-color .28s;
}
.contact-item:hover { transform: translateY(-5px); border-color: rgba(34, 211, 238, 0.45); }
.contact-icon {
  width: 52px; height: 52px;
  margin: 0 auto 16px;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px;
  color: var(--accent);
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.28);
  border-radius: 50%;
}
.contact-item h3 { font-size: 16px; margin-bottom: 8px; }
.contact-item p { font-size: 14px; color: var(--text-dim); }
.contact-item a:hover { color: var(--accent); }

/* ---------- 页脚 ---------- */
.site-footer { background: #070d1a; border-top: 1px solid var(--line); padding: 56px 0 0; }
.footer-top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 44px;
}
.footer-brand p { margin-top: 16px; font-size: 13.5px; color: var(--text-dim); max-width: 420px; }
.footer-links h4 { font-size: 15px; margin-bottom: 14px; color: #fff; }
.footer-links a { display: block; font-size: 13.5px; color: var(--text-dim); margin-bottom: 10px; transition: color .25s; }
.footer-links a:hover { color: var(--accent); }

.footer-bottom {
  border-top: 1px solid var(--line);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 13px;
  color: var(--text-dim);
}
.footer-bottom a { transition: color .25s; }
.footer-bottom a:hover { color: var(--accent); }

/* ---------- 滚动渐入动画 ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3, .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 1fr; gap: 28px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }

  .nav-toggle { display: block; }
  .main-nav {
    position: fixed;
    top: 68px; right: 0;
    width: min(300px, 80vw);
    height: calc(100vh - 68px);
    background: rgba(10, 16, 30, 0.98);
    border-left: 1px solid var(--line);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 24px 28px;
    transform: translateX(100%);
    transition: transform .3s ease;
  }
  .main-nav.open { transform: none; }
  .main-nav a { display: block; padding: 14px 0; font-size: 16px; width: 100%; border-bottom: 1px solid rgba(148, 187, 255, 0.08); }
  .main-nav .nav-cta { text-align: center; border: 0; margin-top: 20px; }
}

@media (max-width: 640px) {
  .section { padding: 72px 0; }
  .grid-2, .grid-3, .grid-4, .steps { grid-template-columns: 1fr; }
  .hero { padding-top: 110px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .footer-bottom { justify-content: center; text-align: center; }
}

/* ---------- 功能标签 chip ---------- */
.chip {
  display: inline-block;
  font-size: 12px;
  line-height: 1;
  padding: 5px 10px;
  margin-bottom: 12px;
  color: var(--accent);
  background: rgba(34, 211, 238, 0.08);
  border: 1px solid rgba(34, 211, 238, 0.3);
  border-radius: 999px;
  letter-spacing: .5px;
}

/* ---------- 防护原理流程 ---------- */
.flow {
  display: grid;
  grid-template-columns: 1fr auto 1.4fr auto 1fr;
  align-items: stretch;
  gap: 18px;
  max-width: 980px;
  margin: 0 auto;
}
.flow-node {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px;
  text-align: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 10px;
  transition: border-color .28s, transform .28s;
}
.flow-node:hover { border-color: rgba(34, 211, 238, 0.45); transform: translateY(-4px); }
.flow-icon { font-size: 30px; line-height: 1; }
.flow-node h4 { font-size: 15px; }
.flow-node p { font-size: 13px; color: var(--text-dim); }
.flow-core {
  border-color: rgba(34, 211, 238, 0.4);
  background: linear-gradient(160deg, rgba(34, 211, 238, 0.1), rgba(59, 130, 246, 0.08)), var(--card);
}
.flow-core ul { list-style: none; text-align: left; display: grid; gap: 7px; }
.flow-core li { font-size: 13.5px; color: var(--text-dim); padding-left: 18px; position: relative; }
.flow-core li::before {
  content: "";
  position: absolute;
  left: 0; top: 8px;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--grad);
}
.flow-arrow {
  align-self: center;
  font-size: 24px;
  color: var(--accent);
  text-align: center;
}
.flow-note { max-width: 760px; margin: 30px auto 0; text-align: center; font-size: 14px; color: var(--text-dim); }

/* ---------- 案例徽章 ---------- */
.case-badges { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0 14px; }
.case-badge {
  font-size: 12.5px;
  padding: 5px 12px;
  border-radius: 999px;
  color: #0a1a2e;
  font-weight: 600;
  background: linear-gradient(120deg, rgba(34, 211, 238, 0.85), rgba(59, 130, 246, 0.85));
}

/* ---------- FAQ 折叠 ---------- */
.faq-list { max-width: 860px; margin: 0 auto; display: grid; gap: 14px; }
.faq-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  transition: border-color .28s;
}
.faq-item.open { border-color: rgba(34, 211, 238, 0.45); }
.faq-q {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  background: none;
  border: 0;
  color: var(--text);
  font-family: inherit;
  font-size: 15.5px;
  font-weight: 600;
  padding: 18px 22px;
  cursor: pointer;
  text-align: left;
}
.faq-arrow { color: var(--accent); transition: transform .3s; flex: 0 0 auto; }
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .35s ease; }
.faq-item.open .faq-a { max-height: 320px; }
.faq-a p { padding: 0 22px 18px; font-size: 14px; color: var(--text-dim); }

/* ---------- 关于我们（左右布局） ---------- */
.about-layout {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 56px;
  align-items: start;
}
.about-side h2 { font-size: clamp(26px, 3.6vw, 36px); font-weight: 800; }
.about-side h2::after {
  content: "";
  display: block;
  width: 52px; height: 4px;
  margin: 16px 0 0;
  border-radius: 2px;
  background: var(--grad);
}
.about-sub { margin-top: 14px; color: var(--accent); font-size: 15px; }
.about-points { list-style: none; margin-top: 26px; display: grid; gap: 12px; }
.about-points li {
  font-size: 14.5px;
  color: var(--text-dim);
  padding-left: 22px;
  position: relative;
}
.about-points li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}
.about-body { color: var(--text-dim); font-size: 15.5px; display: grid; gap: 18px; }

/* ---------- CTA 横幅 ---------- */
.cta-banner {
  background:
    radial-gradient(700px 300px at 20% 0%, rgba(59, 130, 246, 0.25), transparent 60%),
    linear-gradient(120deg, #0e2a5e, #14397f 55%, #0e2a5e);
  padding: 72px 0;
}
.cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  flex-wrap: wrap;
}
.cta-inner h2 { font-size: clamp(24px, 3.2vw, 32px); font-weight: 800; }
.cta-inner p { margin-top: 10px; color: var(--text-dim); font-size: 15px; }
.btn-lg { padding: 15px 38px; font-size: 16px; }

/* ---------- 联系我们（信息 + 表单） ---------- */
.contact-wrap {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 40px;
  max-width: 980px;
  margin: 0 auto;
}
.contact-info { display: grid; gap: 16px; align-content: start; }
.contact-form {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 28px;
}
.contact-form h3 { font-size: 18px; margin-bottom: 20px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-bottom: 14px; }
.contact-form input,
.contact-form textarea {
  width: 100%;
  font-family: inherit;
  font-size: 14px;
  color: var(--text);
  background: rgba(11, 18, 32, 0.7);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px 14px;
  outline: none;
  transition: border-color .25s;
}
.contact-form input:focus,
.contact-form textarea:focus { border-color: rgba(34, 211, 238, 0.6); }
.contact-form input::placeholder,
.contact-form textarea::placeholder { color: #5d6f8c; }
.contact-form textarea { resize: vertical; margin-bottom: 16px; }
.contact-form .btn { width: 100%; border: 0; cursor: pointer; }
.form-note { margin-top: 12px; font-size: 12.5px; color: var(--text-dim); text-align: center; }

/* ---------- 响应式补充 ---------- */
@media (max-width: 960px) {
  .flow { grid-template-columns: 1fr; gap: 10px; }
  .flow-arrow { transform: rotate(90deg); }
  .about-layout, .contact-wrap { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 640px) {
  .form-row { grid-template-columns: 1fr; }
  .cta-inner { flex-direction: column; text-align: center; }
  .flow-core ul { text-align: center; }
  .flow-core li { padding-left: 0; }
  .flow-core li::before { display: none; }
}