:root {
  --ink: #063855;
  --ink-2: #0e4f70;
  --orange: #f7931e;
  --orange-dark: #d87010;
  --steel: #647583;
  --line: #dce5ea;
  --panel: #f4f8fa;
  --white: #ffffff;
  --shadow: 0 18px 48px rgba(6, 56, 85, 0.16);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.6;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 76px;
  padding: 12px clamp(20px, 5vw, 72px);
  background: rgba(255, 255, 255, 0.93);
  border-bottom: 1px solid rgba(220, 229, 234, 0.72);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  width: min(238px, 54vw);
}

.brand img {
  width: 100%;
}

.nav {
  display: flex;
  align-items: center;
  gap: clamp(18px, 3vw, 34px);
  color: var(--ink-2);
  font-size: 15px;
  font-weight: 700;
}

.nav a {
  position: relative;
  padding: 8px 0;
}

.nav a::after {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  content: "";
  background: var(--orange);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.nav a:hover::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(340px, 0.72fr);
  gap: clamp(28px, 6vw, 86px);
  align-items: center;
  min-height: calc(100vh - 76px);
  padding: clamp(48px, 8vw, 90px) clamp(20px, 5vw, 72px) clamp(36px, 6vw, 64px);
  background:
    linear-gradient(90deg, rgba(255, 255, 255, 0.98), rgba(255, 255, 255, 0.88)),
    repeating-linear-gradient(90deg, rgba(6, 56, 85, 0.07) 0 1px, transparent 1px 84px);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--orange-dark);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 780px;
  margin-bottom: 22px;
  font-size: clamp(42px, 7vw, 84px);
  line-height: 1.05;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0;
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.16;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 12px;
  font-size: 22px;
  line-height: 1.25;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 710px;
  margin-bottom: 30px;
  color: #405866;
  font-size: clamp(18px, 2vw, 22px);
}

.hero-actions,
.hero-stats,
.service-grid,
.timeline {
  display: grid;
}

.hero-actions {
  grid-template-columns: repeat(2, max-content);
  gap: 14px;
  align-items: center;
  margin-bottom: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid var(--ink);
  border-radius: 6px;
  font-weight: 900;
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 26px rgba(6, 56, 85, 0.16);
}

.button.primary {
  color: white;
  background: var(--orange);
  border-color: var(--orange);
}

.button.secondary {
  color: var(--ink);
  background: white;
}

.hero-stats {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  max-width: 700px;
  margin: 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.hero-stats div {
  padding: 18px 20px 18px 0;
}

.hero-stats dt {
  font-size: 24px;
  font-weight: 900;
}

.hero-stats dd {
  margin: 3px 0 0;
  color: var(--steel);
  font-size: 14px;
}

.hero-media {
  display: grid;
  place-items: center;
  min-height: 360px;
  padding: clamp(24px, 3vw, 34px);
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.98), rgba(244, 248, 250, 0.9)),
    radial-gradient(circle at 24% 24%, rgba(247, 147, 30, 0.14), transparent 38%);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.hero-media img {
  width: min(430px, 100%);
  aspect-ratio: 1 / 1;
  object-fit: contain;
}

.service-band,
.strengths,
.process,
.contact {
  padding: clamp(58px, 9vw, 110px) clamp(20px, 5vw, 72px);
}

.section-heading {
  display: grid;
  gap: 4px;
  max-width: 860px;
  margin-bottom: clamp(28px, 5vw, 46px);
}

.service-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.service-card {
  min-height: 286px;
  padding: 28px;
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.service-card:nth-child(even) {
  background: var(--panel);
}

.service-index {
  display: inline-flex;
  margin-bottom: 54px;
  color: var(--orange);
  font-size: 14px;
  font-weight: 900;
}

.service-card p,
.strength-panel p,
.timeline p,
.contact p {
  color: #4f6673;
}

.strengths {
  color: white;
  background: var(--ink);
}

.strengths .eyebrow {
  color: #ffb24d;
}

.strength-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(300px, 1.1fr);
  gap: clamp(24px, 5vw, 60px);
  align-items: start;
}

.strength-panel {
  padding: 34px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
}

.strength-panel p {
  color: rgba(255, 255, 255, 0.78);
}

.check-list {
  display: grid;
  gap: 14px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding: 17px 20px 17px 48px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.13);
  border-radius: 8px;
}

.check-list li::before {
  position: absolute;
  left: 18px;
  top: 19px;
  width: 15px;
  height: 15px;
  content: "";
  background: var(--orange);
  clip-path: polygon(14% 46%, 38% 72%, 86% 16%, 100% 29%, 40% 91%, 0 55%);
}

.process {
  background: #f8fbfc;
}

.timeline {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.timeline article {
  position: relative;
  min-height: 220px;
  padding: 28px;
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.timeline span {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  margin-bottom: 42px;
  color: white;
  font-weight: 900;
  background: var(--ink);
  border-radius: 50%;
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.72fr);
  gap: clamp(24px, 5vw, 70px);
  align-items: center;
  color: white;
  background:
    linear-gradient(135deg, rgba(6, 56, 85, 0.96), rgba(14, 79, 112, 0.92)),
    url("assets/yuanheng-logo-optimized.svg");
  background-size: cover, min(620px, 82vw);
  background-position: center, right center;
  background-repeat: no-repeat;
}

.contact .eyebrow {
  color: #ffb24d;
}

.contact p {
  max-width: 660px;
  color: rgba(255, 255, 255, 0.8);
}

.contact-box {
  display: grid;
  gap: 16px;
  padding: 30px;
  color: var(--ink);
  background: white;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.contact-box span {
  color: var(--steel);
  font-size: 14px;
  font-weight: 700;
}

.contact-box > a:not(.button) {
  color: var(--ink);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 900;
  overflow-wrap: anywhere;
}

.contact-methods {
  display: grid;
  gap: 12px;
  margin-top: 4px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.contact-method {
  display: grid;
  gap: 4px;
}

.contact-method__label {
  color: var(--steel);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
}

.contact-method__value {
  color: var(--ink);
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 800;
  overflow-wrap: anywhere;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  padding: 24px clamp(20px, 5vw, 72px);
  color: #4f6673;
  border-top: 1px solid var(--line);
}

.site-footer img {
  width: 190px;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 1080px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-media {
    min-height: 340px;
  }

  .service-grid,
  .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .site-header {
    min-height: 66px;
  }

  .brand {
    width: min(210px, 62vw);
  }

  .nav-toggle {
    display: inline-grid;
    place-items: center;
    gap: 5px;
    width: 42px;
    height: 42px;
    padding: 0;
    background: white;
    border: 1px solid var(--line);
    border-radius: 6px;
  }

  .nav-toggle span {
    width: 18px;
    height: 2px;
    background: var(--ink);
  }

  .nav {
    position: fixed;
    left: 16px;
    right: 16px;
    top: 76px;
    display: none;
    padding: 16px;
    background: white;
    border: 1px solid var(--line);
    border-radius: 8px;
    box-shadow: var(--shadow);
  }

  .nav.is-open {
    display: grid;
  }

  .hero {
    padding-top: 42px;
  }

  .hero-actions,
  .hero-stats,
  .service-grid,
  .timeline,
  .strength-layout,
  .contact {
    grid-template-columns: 1fr;
  }

  .button {
    width: 100%;
  }

  .hero-media {
    min-height: 220px;
    padding: 24px;
  }

  .service-card,
  .timeline article {
    min-height: auto;
  }

  .service-index,
  .timeline span {
    margin-bottom: 28px;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }
}