/* ============================================================
   泰凌特科技 TLT TECH — 企业官网样式
   蓝色科技风格 / 响应式
   ============================================================ */

:root {
  --navy-900: #050e24;
  --navy-800: #081633;
  --navy-700: #0a1f44;
  --blue-700: #1d4ed8;
  --blue-600: #2563eb;
  --blue-500: #3b82f6;
  --blue-400: #60a5fa;
  --sky-400: #38bdf8;
  --ink-900: #0f1c33;
  --ink-600: #41527a;
  --ink-400: #64748b;
  --line: #e3eaf6;
  --bg-soft: #f4f7fd;
  --white: #ffffff;
  --grad: linear-gradient(135deg, #2563eb 0%, #38bdf8 100%);
  --shadow-card: 0 10px 30px rgba(23, 58, 138, 0.08);
  --shadow-hover: 0 18px 44px rgba(37, 99, 235, 0.18);
  --radius: 16px;
  --header-h: 72px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue",
    Arial, sans-serif;
}

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

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

body {
  font-family: var(--font);
  color: var(--ink-900);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

.container {
  width: min(1180px, 92%);
  margin: 0 auto;
}

/* ---------------- 导航栏 ---------------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: transparent;
  transition: background 0.35s ease, box-shadow 0.35s ease, backdrop-filter 0.35s ease;
}

.site-header.scrolled {
  background: rgba(6, 15, 36, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 6px 24px rgba(3, 10, 28, 0.35);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.brand-logo {
  width: 38px;
  height: 38px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
  font-size: 1.06rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.02em;
}

.brand-text small {
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.22em;
  color: rgba(255, 255, 255, 0.55);
}

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

.nav-link {
  position: relative;
  padding: 8px 14px;
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.78);
  border-radius: 8px;
  transition: color 0.25s ease, background 0.25s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--grad);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
  color: #fff;
}

.nav-link:hover::after,
.nav-link.active::after {
  transform: scaleX(1);
}

.nav-cta {
  margin-left: 10px;
  padding: 9px 20px;
  background: var(--grad);
  color: #fff;
  font-weight: 600;
  border-radius: 999px;
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.35);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.nav-cta::after {
  display: none;
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(37, 99, 235, 0.45);
}

/* 移动端菜单按钮 */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 10px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: #fff;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------------- Hero 首屏 ---------------- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #fff;
  padding: calc(var(--header-h) + 48px) 0 96px;
  background:
    radial-gradient(1100px 600px at 75% -10%, rgba(37, 99, 235, 0.35), transparent 60%),
    radial-gradient(900px 520px at 10% 110%, rgba(14, 165, 233, 0.22), transparent 60%),
    linear-gradient(180deg, var(--navy-900) 0%, var(--navy-700) 100%);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(96, 165, 250, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(96, 165, 250, 0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(ellipse 90% 75% at 50% 40%, #000 25%, transparent 75%);
  mask-image: radial-gradient(ellipse 90% 75% at 50% 40%, #000 25%, transparent 75%);
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.5;
  will-change: transform;
}

.orb-1 {
  width: 420px;
  height: 420px;
  background: #1d4ed8;
  top: -120px;
  right: -80px;
  animation: drift 14s ease-in-out infinite;
}

.orb-2 {
  width: 360px;
  height: 360px;
  background: #0ea5e9;
  bottom: -140px;
  left: -100px;
  animation: drift 18s ease-in-out infinite reverse;
}

.orb-3 {
  width: 260px;
  height: 260px;
  background: #2563eb;
  top: 42%;
  left: 56%;
  opacity: 0.32;
  animation: drift 16s ease-in-out infinite;
}

@keyframes drift {
  0%,
  100% {
    transform: translate(0, 0);
  }
  50% {
    transform: translate(34px, -34px);
  }
}

.hero-inner {
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: #bfdbfe;
  background: rgba(37, 99, 235, 0.16);
  border: 1px solid rgba(96, 165, 250, 0.35);
  border-radius: 999px;
  backdrop-filter: blur(6px);
}

.hero-badge svg {
  width: 15px;
  height: 15px;
}

.hero-title {
  margin: 28px auto 22px;
  font-size: clamp(2.3rem, 5.4vw, 3.9rem);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: 0.01em;
}

.grad-text {
  background: linear-gradient(90deg, #60a5fa 0%, #38bdf8 60%, #7dd3fc 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 720px;
  margin: 0 auto 38px;
  font-size: clamp(0.98rem, 1.4vw, 1.12rem);
  color: rgba(226, 236, 255, 0.78);
}

.hero-sub strong {
  color: #93c5fd;
  font-weight: 600;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 64px;
}

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 30px;
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
}

.btn svg {
  width: 18px;
  height: 18px;
}

.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 10px 26px rgba(37, 99, 235, 0.4);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 34px rgba(37, 99, 235, 0.5);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.06);
  color: #dbeafe;
  border: 1px solid rgba(147, 197, 253, 0.4);
  backdrop-filter: blur(6px);
}

.btn-ghost:hover {
  transform: translateY(-3px);
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(147, 197, 253, 0.7);
}

.btn-block {
  width: 100%;
}

/* ---------------- Hero 数据 ---------------- */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  max-width: 780px;
  margin: 0 auto;
}

.stat {
  padding: 22px 18px;
  background: rgba(255, 255, 255, 0.045);
  border: 1px solid rgba(96, 165, 250, 0.22);
  border-radius: var(--radius);
  backdrop-filter: blur(8px);
  transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}

.stat:hover {
  transform: translateY(-4px);
  border-color: rgba(96, 165, 250, 0.5);
  background: rgba(255, 255, 255, 0.07);
}

.stat strong {
  display: block;
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1.2;
  background: linear-gradient(90deg, #93c5fd, #38bdf8);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.stat strong span {
  font-size: 1.05rem;
  font-weight: 600;
  margin-left: 2px;
}

.stat-label {
  display: block;
  margin-top: 6px;
  font-size: 0.82rem;
  color: rgba(191, 219, 254, 0.72);
}

/* ---------------- 滚动提示 ---------------- */
.scroll-hint {
  position: absolute;
  left: 50%;
  bottom: 30px;
  transform: translateX(-50%);
  z-index: 1;
}

.mouse {
  display: block;
  width: 26px;
  height: 42px;
  border: 2px solid rgba(147, 197, 253, 0.5);
  border-radius: 14px;
  position: relative;
}

.wheel {
  position: absolute;
  left: 50%;
  top: 8px;
  width: 4px;
  height: 8px;
  margin-left: -2px;
  border-radius: 3px;
  background: #60a5fa;
  animation: wheel 1.8s ease-in-out infinite;
}

@keyframes wheel {
  0% {
    opacity: 1;
    transform: translateY(0);
  }
  70% {
    opacity: 0;
    transform: translateY(14px);
  }
  100% {
    opacity: 0;
    transform: translateY(0);
  }
}

/* ---------------- 通用 Section ---------------- */
.section {
  padding: 104px 0;
}

.section-tag {
  display: inline-block;
  padding: 6px 16px;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--blue-600);
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(37, 99, 235, 0.18);
  border-radius: 999px;
}

.section-tag-light {
  color: #93c5fd;
  background: rgba(56, 189, 248, 0.1);
  border-color: rgba(56, 189, 248, 0.28);
}

.section-head {
  max-width: 720px;
  margin: 0 auto 60px;
  text-align: center;
}

.section-head h2 {
  margin: 18px 0 14px;
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  font-weight: 800;
  line-height: 1.35;
}

.section-head p {
  color: var(--ink-400);
  font-size: 1rem;
}

/* ---------------- 关于我们 ---------------- */
.about {
  background: var(--white);
}

.about-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 64px;
  align-items: center;
}

.about-card {
  position: relative;
  padding: 36px 32px;
  background: linear-gradient(160deg, #0a1f44 0%, #123468 100%);
  border-radius: 20px;
  color: #fff;
  box-shadow: 0 24px 60px rgba(10, 31, 68, 0.35);
  overflow: hidden;
}

.about-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(96, 165, 250, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(96, 165, 250, 0.1) 1px, transparent 1px);
  background-size: 34px 34px;
  -webkit-mask-image: radial-gradient(circle at 85% 0%, #000 0%, transparent 65%);
  mask-image: radial-gradient(circle at 85% 0%, #000 0%, transparent 65%);
}

.about-card > * {
  position: relative;
}

.about-card-head {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: #7dd3fc;
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 999px;
}

.about-card-head svg {
  width: 14px;
  height: 14px;
}

.about-card h3 {
  margin: 20px 0 6px;
  font-size: 1.5rem;
  font-weight: 700;
}

.about-card-addr {
  color: rgba(219, 234, 254, 0.85);
  font-size: 0.98rem;
}

.about-card-note {
  margin-top: 4px;
  font-size: 0.85rem;
  color: rgba(147, 197, 253, 0.6);
}

.eco-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0 14px;
}

.eco-list li {
  padding: 7px 16px;
  font-size: 0.86rem;
  font-weight: 500;
  color: #dbeafe;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(147, 197, 253, 0.28);
  border-radius: 999px;
}

.eco-note {
  font-size: 0.84rem;
  color: rgba(191, 219, 254, 0.65);
}

.about-text h2 {
  margin: 18px 0 20px;
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  font-weight: 800;
  line-height: 1.4;
}

.about-text p {
  margin-bottom: 16px;
  color: var(--ink-600);
}

.check-list {
  margin-top: 26px;
  display: grid;
  gap: 14px;
}

.check-list li {
  position: relative;
  padding-left: 38px;
  font-weight: 500;
  color: var(--ink-900);
}

.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 2px;
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: rgba(37, 99, 235, 0.1);
  border: 1px solid rgba(37, 99, 235, 0.25);
}

.check-list li::after {
  content: "";
  position: absolute;
  left: 8px;
  top: 9px;
  width: 10px;
  height: 6px;
  border-left: 2px solid var(--blue-600);
  border-bottom: 2px solid var(--blue-600);
  transform: rotate(-45deg);
}

/* ---------------- 核心业务 ---------------- */
.services {
  background: var(--bg-soft);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  padding: 34px 28px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-8px);
  border-color: rgba(37, 99, 235, 0.35);
  box-shadow: var(--shadow-hover);
}

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 58px;
  height: 58px;
  margin-bottom: 22px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.12), rgba(56, 189, 248, 0.12));
  border: 1px solid rgba(37, 99, 235, 0.2);
  color: var(--blue-600);
  transition: background 0.3s ease, color 0.3s ease, transform 0.3s ease;
}

.feature-icon svg {
  width: 28px;
  height: 28px;
}

.feature-card:hover .feature-icon {
  background: var(--grad);
  color: #fff;
  transform: scale(1.05);
}

.feature-card h3 {
  margin-bottom: 10px;
  font-size: 1.16rem;
  font-weight: 700;
}

.feature-card p {
  font-size: 0.92rem;
  color: var(--ink-400);
}

/* ---------------- 解决方案（深色区） ---------------- */
.solutions {
  position: relative;
  color: #fff;
  background: linear-gradient(180deg, var(--navy-900) 0%, var(--navy-700) 100%);
  overflow: hidden;
}

.solutions-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(96, 165, 250, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(96, 165, 250, 0.06) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(ellipse 80% 80% at 50% 30%, #000 20%, transparent 80%);
  mask-image: radial-gradient(ellipse 80% 80% at 50% 30%, #000 20%, transparent 80%);
}

.solutions::before {
  content: "";
  position: absolute;
  top: -160px;
  left: 50%;
  transform: translateX(-50%);
  width: 640px;
  height: 320px;
  background: radial-gradient(ellipse, rgba(37, 99, 235, 0.4), transparent 70%);
  filter: blur(60px);
  pointer-events: none;
}

.solutions-inner {
  position: relative;
  z-index: 1;
}

.solutions .section-head h2 {
  color: #fff;
}

.solutions .section-head p {
  color: rgba(191, 219, 254, 0.65);
}

.solution-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 18px;
}

.solution-card {
  padding: 30px 22px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(96, 165, 250, 0.2);
  border-radius: var(--radius);
  backdrop-filter: blur(6px);
  transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}

.solution-card:hover {
  transform: translateY(-8px);
  border-color: rgba(56, 189, 248, 0.55);
  background: rgba(37, 99, 235, 0.12);
}

.solution-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  margin-bottom: 18px;
  border-radius: 12px;
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.32);
  color: #7dd3fc;
  transition: transform 0.3s ease;
}

.solution-icon svg {
  width: 26px;
  height: 26px;
}

.solution-card:hover .solution-icon {
  transform: scale(1.08);
}

.solution-card h3 {
  margin-bottom: 8px;
  font-size: 1.1rem;
  font-weight: 700;
}

.solution-card p {
  font-size: 0.86rem;
  color: rgba(191, 219, 254, 0.66);
}

/* ---------------- 技术优势 ---------------- */
.advantages {
  background: var(--white);
}

.adv-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.adv-item {
  display: flex;
  gap: 18px;
  padding: 26px 24px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.adv-item:hover {
  transform: translateY(-6px);
  border-color: rgba(37, 99, 235, 0.3);
  box-shadow: var(--shadow-card);
}

.adv-icon {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  border-radius: 12px;
  background: var(--grad);
  color: #fff;
  box-shadow: 0 8px 18px rgba(37, 99, 235, 0.3);
}

.adv-icon svg {
  width: 24px;
  height: 24px;
}

.adv-item h3 {
  margin-bottom: 6px;
  font-size: 1.05rem;
  font-weight: 700;
}

.adv-item p {
  font-size: 0.88rem;
  color: var(--ink-400);
}

/* ---------------- 合作流程 ---------------- */
.process {
  margin-top: 76px;
  padding: 48px 40px 52px;
  background: linear-gradient(135deg, #0a1f44 0%, #123468 100%);
  border-radius: 22px;
  color: #fff;
  box-shadow: 0 24px 60px rgba(10, 31, 68, 0.3);
}

.process-title {
  margin-bottom: 40px;
  text-align: center;
  font-size: 1.4rem;
  font-weight: 700;
}

.process-steps {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr auto 1fr;
  gap: 18px;
  align-items: stretch;
}

.step {
  padding: 26px 20px;
  text-align: center;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(96, 165, 250, 0.22);
  border-radius: 14px;
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.step:hover {
  transform: translateY(-6px);
  border-color: rgba(56, 189, 248, 0.5);
}

.step-num {
  display: inline-block;
  margin-bottom: 14px;
  font-size: 1.9rem;
  font-weight: 800;
  background: linear-gradient(90deg, #60a5fa, #38bdf8);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.step h4 {
  margin-bottom: 8px;
  font-size: 1.02rem;
  font-weight: 700;
}

.step p {
  font-size: 0.82rem;
  color: rgba(191, 219, 254, 0.62);
}

.step-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(96, 165, 250, 0.55);
}

.step-arrow svg {
  width: 26px;
  height: 26px;
}

/* ---------------- 联系我们 ---------------- */
.contact {
  background: var(--bg-soft);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}

.contact-info h2 {
  margin: 18px 0 16px;
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  font-weight: 800;
  line-height: 1.4;
}

.contact-lead {
  color: var(--ink-400);
  margin-bottom: 34px;
}

.contact-list {
  display: grid;
  gap: 22px;
}

.contact-list li {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.contact-icon {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
  color: var(--blue-600);
}

.contact-icon svg {
  width: 22px;
  height: 22px;
}

.contact-list strong {
  display: block;
  margin-bottom: 2px;
  font-size: 0.98rem;
}

.contact-list span {
  font-size: 0.9rem;
  color: var(--ink-400);
}

/* 表单 */
.contact-form-wrap {
  padding: 40px 36px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
}

.contact-form h3 {
  margin-bottom: 26px;
  font-size: 1.3rem;
  font-weight: 700;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-field {
  margin-bottom: 18px;
}

.form-field label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--ink-900);
}

.optional {
  font-weight: 400;
  color: var(--ink-400);
}

.form-field input,
.form-field textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 0.94rem;
  font-family: inherit;
  color: var(--ink-900);
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 10px;
  outline: none;
  transition: border-color 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
  resize: vertical;
}

.form-field input::placeholder,
.form-field textarea::placeholder {
  color: #9aa8c2;
}

.form-field input:focus,
.form-field textarea:focus {
  border-color: var(--blue-500);
  background: var(--white);
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.12);
}

.form-msg {
  margin-top: 14px;
  font-size: 0.92rem;
  font-weight: 600;
  color: #16a34a;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

.form-msg.show {
  opacity: 1;
  transform: translateY(0);
}

.form-tip {
  margin-top: 12px;
  font-size: 0.78rem;
  color: #9aa8c2;
}

/* ---------------- 页脚 ---------------- */
.site-footer {
  background: var(--navy-900);
  color: rgba(219, 234, 254, 0.72);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 48px;
  padding: 72px 0 56px;
}

.footer-brand p {
  margin-top: 18px;
  max-width: 320px;
  font-size: 0.88rem;
  color: rgba(147, 197, 253, 0.55);
}

.brand-light .brand-text {
  color: #fff;
}

.footer-col h4 {
  margin-bottom: 20px;
  font-size: 0.98rem;
  font-weight: 700;
  color: #fff;
}

.footer-col ul {
  display: grid;
  gap: 12px;
}

.footer-col a {
  font-size: 0.9rem;
  color: rgba(219, 234, 254, 0.62);
  transition: color 0.25s ease, padding-left 0.25s ease;
}

.footer-col a:hover {
  color: #7dd3fc;
  padding-left: 4px;
}

.footer-contact li {
  font-size: 0.9rem;
  color: rgba(219, 234, 254, 0.62);
}

.footer-bottom {
  padding: 22px 0;
  border-top: 1px solid rgba(96, 165, 250, 0.14);
  text-align: center;
}

.footer-bottom p {
  font-size: 0.82rem;
  color: rgba(147, 197, 253, 0.5);
}

.icp-line {
  margin-top: 6px;
}

.icp-line a {
  color: rgba(147, 197, 253, 0.5);
  transition: color 0.25s ease;
}

.icp-line a:hover {
  color: #7dd3fc;
}

/* ---------------- 返回顶部 ---------------- */
.back-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  z-index: 90;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--grad);
  color: #fff;
  border: none;
  border-radius: 14px;
  box-shadow: 0 12px 28px rgba(37, 99, 235, 0.4);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
}

.back-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-top:hover {
  transform: translateY(-4px);
}

.back-top svg {
  width: 22px;
  height: 22px;
}

/* ---------------- 入场动画 ---------------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .orb,
  .wheel {
    animation: none;
  }
}

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

  .solution-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .about-grid,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about-visual {
    max-width: 560px;
  }

  .process {
    padding: 40px 28px 44px;
  }
}

@media (max-width: 860px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 16px 4vw 22px;
    background: rgba(6, 15, 36, 0.96);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(96, 165, 250, 0.18);
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
  }

  .site-nav.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-link {
    padding: 12px 16px;
    font-size: 1rem;
  }

  .nav-link::after {
    display: none;
  }

  .nav-link.active {
    background: rgba(37, 99, 235, 0.18);
  }

  .nav-cta {
    margin: 10px 0 0;
    text-align: center;
  }

  .process-steps {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .step-arrow {
    transform: rotate(90deg);
    padding: 2px 0;
  }
}

@media (max-width: 640px) {
  .section {
    padding: 76px 0;
  }

  .hero {
    padding-bottom: 84px;
  }

  .hero-stats {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .stat {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 10px;
    padding: 16px 14px;
  }

  .stat strong {
    font-size: 1.7rem;
  }

  .stat-label {
    margin-top: 0;
  }

  .card-grid,
  .adv-grid,
  .solution-grid {
    grid-template-columns: 1fr;
  }

  .form-row {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 36px;
    padding: 56px 0 44px;
  }

  .contact-form-wrap {
    padding: 30px 22px;
  }

  .back-top {
    right: 18px;
    bottom: 18px;
  }

  .brand-text {
    font-size: 0.98rem;
  }
}