/* ===== 1. Reset & Variables ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
:root {
  --color-primary: #1E4F8A;
  --color-primary-deep: #0A1B32;
  --color-surface: #F5F8FC;
  --color-accent: #FF6B35;
  --color-success: #17A36F;
  --color-muted: #B8C6D9;
  --color-shadow: #8FA8C8;
  --color-alert: #E85D46;
  --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, sans-serif;
  --font-heading: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-data: 'JetBrains Mono', 'SFMono-Regular', Consolas, monospace;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 8px;
  --shadow-card: 0 8px 24px rgba(143, 168, 200, 0.35);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --container-width: 1440px;
  --header-h: 76px;
}
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-primary-deep);
  background-color: var(--color-surface);
  min-height: 100vh;
}
img, svg, video {
  display: block;
  max-width: 100%;
}
ul, ol {
  list-style: none;
}
a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s ease;
}
a:hover {
  color: var(--color-accent);
}
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-primary-deep);
}
:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 4px;
}
::selection {
  background: var(--color-accent);
  color: #fff;
}

/* ===== 2. Layout ===== */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: 24px;
}
.main-content {
  min-height: 70vh;
  padding-top: var(--header-h);
}
.content-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 24px;
}

/* ===== 3. Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.92rem;
  line-height: 1;
  padding: 12px 24px;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
}
.btn:hover {
  transform: translateY(-2px);
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--color-primary-deep);
  color: #fff;
  box-shadow: 0 8px 20px rgba(30, 79, 138, 0.35);
}
.btn-accent {
  background: var(--color-accent);
  color: #fff;
}
.btn-accent:hover {
  background: #E85D46;
  color: #fff;
  box-shadow: 0 8px 20px rgba(255, 107, 53, 0.4);
}
.btn-sm {
  padding: 9px 18px;
  font-size: 0.85rem;
}

/* ===== 4. Progress Bar ===== */
.progress-bar {
  position: absolute;
  top: 0;
  left: 0;
  width: 0%;
  height: 4px;
  background: var(--color-accent);
  z-index: 10;
  transition: width 0.1s linear;
}

/* ===== 5. Skip Link ===== */
.skip-link {
  position: absolute;
  top: -100px;
  left: 24px;
  z-index: 2000;
  background: var(--color-accent);
  color: #fff;
  padding: 10px 20px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9rem;
  transition: top 0.2s ease;
}
.skip-link:focus {
  top: 16px;
  color: #fff;
}

/* ===== 6. Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: linear-gradient(180deg, rgba(10, 27, 50, 0.72) 0%, rgba(10, 27, 50, 0.28) 70%, rgba(10, 27, 50, 0) 100%);
  transition: background var(--transition), box-shadow var(--transition);
}
.site-header.is-scrolled {
  background: rgba(245, 248, 252, 0.92);
  box-shadow: 0 4px 24px rgba(30, 79, 138, 0.12);
}
.site-header.is-scrolled .progress-bar {
  background: var(--color-accent);
}
.header-inner {
  position: relative;
  max-width: var(--container-width);
  margin-inline: auto;
  height: var(--header-h);
  padding-inline: 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-start;
  line-height: 1.1;
  text-decoration: none;
}
.brand-name {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: 0.04em;
  transition: color var(--transition);
}
.brand-en {
  font-family: var(--font-data);
  font-size: 0.62rem;
  color: var(--color-muted);
  letter-spacing: 0.18em;
  transition: color var(--transition);
}
.site-header.is-scrolled .brand-name {
  color: var(--color-primary-deep);
}
.site-header.is-scrolled .brand-en {
  color: var(--color-primary);
}
.site-nav {
  display: flex;
  align-items: center;
}
.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-list a {
  display: inline-block;
  padding: 8px 16px;
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 500;
  color: #fff;
  border-radius: 999px;
  transition: color 0.2s ease, background-color 0.2s ease;
}
.nav-list a:hover {
  color: var(--color-accent);
  background-color: rgba(255, 255, 255, 0.12);
}
.nav-list a[aria-current="page"] {
  color: var(--color-accent);
  font-weight: 700;
  background-color: rgba(255, 255, 255, 0.14);
}
.site-header.is-scrolled .nav-list a {
  color: var(--color-primary-deep);
}
.site-header.is-scrolled .nav-list a:hover {
  color: var(--color-accent);
  background-color: rgba(30, 79, 138, 0.08);
}
.site-header.is-scrolled .nav-list a[aria-current="page"] {
  color: var(--color-accent);
  background-color: rgba(255, 107, 53, 0.12);
}
.header-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-shrink: 0;
}
.header-phone {
  font-family: var(--font-data);
  font-size: 0.85rem;
  font-weight: 500;
  color: #fff;
  letter-spacing: 0.04em;
  transition: color var(--transition);
}
.site-header.is-scrolled .header-phone {
  color: var(--color-primary-deep);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  background: transparent;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  gap: 5px;
}
.toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease, background-color 0.2s ease;
}
.site-header.is-scrolled .toggle-bar {
  background: var(--color-primary-deep);
}
.nav-toggle[aria-expanded="true"] .toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .toggle-bar:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}
.site-header.is-scrolled .nav-toggle[aria-expanded="true"] .toggle-bar {
  background: var(--color-primary-deep);
}
.nav-toggle:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

/* ===== 7. Footer ===== */
.site-footer {
  background: var(--color-primary-deep);
  color: rgba(245, 248, 252, 0.85);
  font-size: 0.9rem;
  margin-top: 80px;
}
.footer-main {
  max-width: var(--container-width);
  margin-inline: auto;
  padding: 64px 32px 40px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 48px;
}
.footer-brand-col {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.footer-brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.footer-logo {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: 0.04em;
}
.footer-logo-en {
  font-family: var(--font-data);
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.14em;
}
.footer-desc {
  max-width: 320px;
  line-height: 1.7;
  color: rgba(245, 248, 252, 0.7);
}
.trust-note {
  background: rgba(255, 107, 53, 0.12);
  border-left: 3px solid var(--color-alert);
  padding: 10px 14px;
  border-radius: 0 12px 12px 0;
  font-size: 0.82rem;
  line-height: 1.5;
  color: rgba(245, 248, 252, 0.8);
}
.footer-col {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.footer-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.06em;
  padding-bottom: 8px;
  border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}
.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-links a {
  color: rgba(245, 248, 252, 0.75);
  transition: color 0.2s ease, padding-left 0.2s ease;
}
.footer-links a:hover {
  color: var(--color-accent);
  padding-left: 6px;
}
.footer-meta {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.82rem;
  color: rgba(245, 248, 252, 0.55);
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}
.footer-bottom-inner {
  max-width: var(--container-width);
  margin-inline: auto;
  padding: 20px 32px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  font-size: 0.8rem;
  color: rgba(245, 248, 252, 0.5);
}

/* ===== 8. Shared Components ===== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--color-muted);
  padding: 16px 0 8px;
}
.breadcrumb a {
  color: var(--color-primary);
}
.breadcrumb a:hover {
  color: var(--color-accent);
}
.breadcrumb span[aria-current="page"] {
  color: var(--color-primary-deep);
  font-weight: 600;
}
.card {
  background: #fff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 24px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(30, 79, 138, 0.18);
}
.img-frame {
  position: relative;
  width: 100%;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-primary), var(--color-shadow));
  aspect-ratio: 16 / 9;
}
.img-frame::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(160deg, rgba(245, 248, 252, 0.12) 0%, rgba(10, 27, 50, 0.35) 100%);
}
.text-accent {
  color: var(--color-accent);
}
.text-success {
  color: var(--color-success);
}
.text-muted {
  color: var(--color-muted);
}

/* ===== 9. Responsive ===== */
@media (max-width: 1024px) {
  .header-inner {
    padding-inline: 20px;
  }
  .nav-list a {
    padding: 8px 12px;
    font-size: 0.9rem;
  }
  .footer-main {
    grid-template-columns: 1.4fr 1fr 1fr;
    gap: 36px;
  }
}
@media (max-width: 768px) {
  :root {
    --header-h: 64px;
  }
  .header-inner {
    padding-inline: 16px;
    height: var(--header-h);
  }
  .brand-name {
    font-size: 1.3rem;
  }
  .header-phone {
    display: none;
  }
  .nav-toggle {
    display: inline-flex;
  }
  .site-header.is-scrolled .nav-toggle .toggle-bar {
    background: var(--color-primary-deep);
  }
  .brand-en {
    font-size: 0.55rem;
  }
  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(82vw, 360px);
    background: var(--color-primary-deep);
    padding: calc(var(--header-h) + 16px) 28px 32px;
    box-shadow: -16px 0 40px rgba(10, 27, 50, 0.3);
    transform: translateX(100%);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    align-items: flex-start;
    overflow-y: auto;
  }
  .site-nav[data-open] {
    transform: translateX(0);
  }
  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    width: 100%;
  }
  .nav-list a {
    display: block;
    width: 100%;
    padding: 12px 16px;
    font-size: 1.05rem;
    color: #fff;
  }
  .nav-list a:hover {
    background: rgba(255, 255, 255, 0.08);
    color: var(--color-accent);
  }
  .nav-list a[aria-current="page"] {
    background: rgba(255, 107, 53, 0.16);
    color: var(--color-accent);
  }
  .site-header.is-scrolled .nav-list a {
    color: #fff;
  }
  .site-header.is-scrolled .nav-list a:hover {
    color: var(--color-accent);
    background: rgba(255, 255, 255, 0.08);
  }
  .site-header.is-scrolled .nav-list a[aria-current="page"] {
    background: rgba(255, 107, 53, 0.16);
    color: var(--color-accent);
  }
  .header-actions {
    gap: 8px;
  }
  .header-actions .btn-sm {
    padding: 8px 14px;
    font-size: 0.8rem;
  }
  .main-content {
    padding-top: var(--header-h);
  }
  .content-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
  }
  .card {
    padding: 18px;
  }
  .footer-main {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 48px 20px 32px;
  }
  .footer-bottom-inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 16px 20px;
    gap: 6px;
  }
  .footer-brand-col {
    max-width: 100%;
  }
}
@media (max-width: 480px) {
  .container {
    padding-inline: 16px;
  }
  .content-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .header-actions .btn-sm {
    display: none;
  }
}

/* ===== 10. Reduced Motion ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html {
    scroll-behavior: auto;
  }
  .site-nav {
    transition: none;
  }
  .progress-bar {
    transition: none;
  }
  .card {
    transition: none;
  }
}

/* ===== 11. Header / Nav Blanket Overlay (mobile backdrop) ===== */
@media (max-width: 768px) {
  body.nav-open {
    overflow: hidden;
  }
  body.nav-open::after {
    content: '';
    position: fixed;
    inset: 0;
    background: rgba(10, 27, 50, 0.55);
    z-index: 999;
  }
}