/* ==========================================================================
   亿克科技官网 · YIKE TECHNOLOGY
   Design tokens — 浅色背景 / 深海军蓝 / 少量金色强调 / 精致细线
   ========================================================================== */

:root {
  /* 品牌色（按需求指定） */
  --color-bg: #F7F8FA;
  --color-surface: #FFFFFF;
  --color-primary: #142238;
  --color-primary-soft: #1D3050;
  --color-text: #111827;
  --color-muted: #667085;
  --color-gold: #C89536;
  --color-gold-light: #E7C36F;
  --color-line: #E3E8F0;
  --color-line-strong: #C9D2DF;

  /* 语义文字 */
  --text-body: 1rem;
  --text-body-line: 1.75;

  /* 动效 */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --duration-slow: 0.7s;
  --duration-mid: 0.3s;
  --duration-fast: 0.15s;
}

/* ==========================================================================
   Reset & base
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: "PingFang SC", "HarmonyOS Sans SC", "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: var(--text-body);
  line-height: var(--text-body-line);
  font-kerning: normal;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

ul,
ol {
  margin: 0;
  padding: 0;
}

::selection {
  background: var(--color-gold-light);
  color: var(--color-primary);
}

:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 3px;
  border-radius: 4px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 100;
  padding: 0.75rem 1.25rem;
  background: var(--color-primary);
  color: #fff;
  border-radius: 8px;
  text-decoration: none;
  font-size: 0.9rem;
  transition: top 0.2s var(--ease-out);
}

.skip-link:focus {
  top: 12px;
}

.container {
  width: min(100% - 2.5rem, 1160px);
  margin-inline: auto;
}

/* ==========================================================================
   Header
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--color-bg);
  border-bottom: 1px solid transparent;
  transition: border-color var(--duration-mid) var(--ease-out), box-shadow var(--duration-mid) var(--ease-out);
}

.site-header.is-scrolled {
  border-bottom-color: var(--color-line);
  box-shadow: 0 8px 24px -20px rgba(20, 34, 56, 0.35);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 76px;
  gap: 1.5rem;
  position: relative;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.8rem;
  text-decoration: none;
}

.brand-logo {
  flex: none;
  height: 40px;
  width: auto;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  color: var(--color-primary);
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.brand-en {
  margin-top: 3px;
  color: var(--color-muted);
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0.26em;
  text-transform: uppercase;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2.25rem;
  list-style: none;
}

.nav-menu a {
  position: relative;
  display: inline-block;
  padding: 0.4rem 0.1rem;
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.97rem;
  transition: color var(--duration-fast) ease;
}

.nav-menu a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--color-gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--duration-mid) var(--ease-out);
}

.nav-menu a:hover,
.nav-menu a:focus-visible {
  color: var(--color-primary);
}

.nav-menu a:hover::after,
.nav-menu a:focus-visible::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 6px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: none;
  border: 0;
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-primary);
  border-radius: 2px;
  transition: transform var(--duration-mid) var(--ease-out), opacity var(--duration-fast) ease;
}

.site-nav.is-open .nav-toggle-bar:nth-child(2) {
  transform: translateY(4px) rotate(45deg);
}

.site-nav.is-open .nav-toggle-bar:nth-child(3) {
  transform: translateY(-4px) rotate(-45deg);
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  position: relative;
  padding: clamp(4.5rem, 10vw, 8.5rem) 0 clamp(4rem, 8vw, 7rem);
  background:
    radial-gradient(720px 420px at 88% -10%, rgba(200, 149, 54, 0.07), transparent 70%),
    linear-gradient(180deg, #F2F5F9 0%, var(--color-bg) 100%);
  border-bottom: 1px solid var(--color-line);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  align-items: center;
  gap: clamp(2.5rem, 6vw, 6rem);
}

.hero-kicker {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin: 0 0 1.6rem;
  color: var(--color-gold);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

.hero-kicker-line {
  width: 40px;
  height: 1px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
}

.hero-title {
  margin: 0;
  color: var(--color-primary);
  font-size: clamp(2.6rem, 5.6vw, 4.35rem);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: 0.015em;
  text-wrap: balance;
}

.hero-sub {
  max-width: 46ch;
  margin: 1.75rem 0 0;
  color: var(--color-muted);
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  line-height: 1.9;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin-top: 2.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.95rem 1.9rem;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: background var(--duration-mid) var(--ease-out), border-color var(--duration-mid) var(--ease-out), color var(--duration-mid) var(--ease-out), transform var(--duration-mid) var(--ease-out), box-shadow var(--duration-mid) var(--ease-out);
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
  box-shadow: 0 10px 22px -14px rgba(20, 34, 56, 0.55);
}

.btn-primary:hover {
  background: var(--color-primary-soft);
  transform: translateY(-2px);
  box-shadow: 0 16px 28px -16px rgba(20, 34, 56, 0.55);
}

.btn-ghost {
  background: transparent;
  border: 1px solid var(--color-line-strong);
  color: var(--color-primary);
}

.btn-ghost:hover {
  border-color: var(--color-gold);
  color: var(--color-primary);
}

.btn-arrow {
  transition: transform var(--duration-mid) var(--ease-out);
}

.btn-primary:hover .btn-arrow {
  transform: translateX(4px);
}

.hero-visual {
  display: flex;
  justify-content: center;
}

.brand-tile {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: min(340px, 100%);
  aspect-ratio: 1;
  border-radius: 20px;
  background:
    radial-gradient(480px 480px at 75% 20%, rgba(231, 195, 111, 0.1), transparent 60%),
    var(--color-primary);
  box-shadow: 0 28px 56px -28px rgba(20, 34, 56, 0.45);
  overflow: hidden;
}

.brand-tile::before {
  content: "";
  position: absolute;
  inset: 9%;
  border: 1px solid rgba(231, 195, 111, 0.28);
  border-radius: 12px;
  pointer-events: none;
}

.brand-tile-logo {
  height: 84px;
  width: auto;
  margin-bottom: 1.4rem;
}

.brand-tile-name {
  color: #fff;
  font-size: 1.55rem;
  font-weight: 700;
  letter-spacing: 0.4em;
  text-indent: 0.4em;
}

.brand-tile-en {
  margin-top: 0.55rem;
  color: var(--color-gold-light);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.32em;
  text-transform: uppercase;
}

.brand-tile-line {
  width: 52px;
  height: 1px;
  margin: 1.4rem 0 0.9rem;
  background: linear-gradient(90deg, transparent, var(--color-gold-light), transparent);
}

.brand-tile-cn {
  color: rgba(255, 255, 255, 0.55);
  font-size: 0.8rem;
  letter-spacing: 0.28em;
  text-indent: 0.28em;
}

/* ==========================================================================
   Sections
   ========================================================================== */

.section {
  padding: clamp(4.5rem, 9vw, 8rem) 0;
}

.about,
.contact {
  background: var(--color-surface);
}

.about-grid,
.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  align-items: start;
  gap: clamp(3rem, 7vw, 6.5rem);
}

.section-kicker {
  margin: 0 0 0.9rem;
  color: var(--color-gold);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

.section-title {
  margin: 0;
  color: var(--color-primary);
  font-size: clamp(1.9rem, 3.4vw, 2.75rem);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: 0.02em;
}

.section-rule {
  display: block;
  width: 56px;
  height: 2px;
  margin-top: 1.5rem;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
  border-radius: 2px;
}

.about-lead {
  margin: 0;
  max-width: 52ch;
  color: var(--color-text);
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  line-height: 1.95;
}

.about-values {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
  margin-top: 2.75rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--color-line);
  list-style: none;
}

.about-values li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--color-muted);
  font-size: 0.95rem;
  letter-spacing: 0.14em;
}

.about-values li::before {
  content: "";
  width: 6px;
  height: 6px;
  background: linear-gradient(135deg, var(--color-gold), var(--color-gold-light));
  transform: rotate(45deg);
}

/* ==========================================================================
   Capabilities
   ========================================================================== */

.capabilities .section-head {
  margin-bottom: clamp(2.5rem, 5vw, 4rem);
}

.cap-list {
  list-style: none;
}

.cap-item {
  display: grid;
  grid-template-areas: "num name desc";
  grid-template-columns: 5.5rem minmax(0, 1fr) minmax(0, 1.25fr);
  align-items: baseline;
  gap: 1.25rem 2rem;
  padding: 2.1rem 0;
  border-top: 1px solid var(--color-line);
  transition: padding-left var(--duration-mid) var(--ease-out);
}

.cap-item:last-child {
  border-bottom: 1px solid var(--color-line);
}

.cap-item:hover {
  padding-left: 0.9rem;
}

.cap-num {
  grid-area: num;
  color: var(--color-muted);
  font-size: 0.95rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.1em;
  transition: color var(--duration-mid) var(--ease-out);
}

.cap-item:hover .cap-num {
  color: var(--color-gold);
}

.cap-name {
  grid-area: name;
  margin: 0;
  color: var(--color-primary);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 600;
  letter-spacing: 0.03em;
  transition: transform var(--duration-mid) var(--ease-out);
}

.cap-item:hover .cap-name {
  transform: translateX(2px);
}

.cap-desc {
  grid-area: desc;
  margin: 0;
  color: var(--color-muted);
  font-size: 0.96rem;
  line-height: 1.8;
}

/* ==========================================================================
   Contact
   ========================================================================== */

.contact-list {
  margin: 0;
}

.contact-row {
  display: grid;
  grid-template-columns: 8.5rem minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--color-line);
}

.contact-row:last-child {
  border-bottom: 1px solid var(--color-line);
}

.contact-row dt {
  color: var(--color-muted);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
}

.contact-row dd {
  margin: 0;
  color: var(--color-text);
  font-size: 1.05rem;
  line-height: 1.9;
}

.contact-mail {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-color: var(--color-gold-light);
  text-underline-offset: 0.35em;
  transition: color var(--duration-fast) ease, text-decoration-color var(--duration-fast) ease;
}

.contact-mail:hover {
  color: var(--color-gold);
  text-decoration-color: var(--color-gold);
}

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  background: var(--color-primary);
  border-top: 1px solid rgba(231, 195, 111, 0.4);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem 2.5rem;
  padding: 2.75rem 0 3rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.footer-logo {
  height: 32px;
  width: auto;
}

.footer-brand-name {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.06em;
}

.footer-brand-en {
  color: var(--color-gold-light);
  font-size: 0.66rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

.footer-copy {
  margin: 0;
  color: rgba(255, 255, 255, 0.68);
  font-size: 0.9rem;
  letter-spacing: 0.04em;
}

.footer-icp {
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--duration-fast) ease, border-color var(--duration-fast) ease;
}

.footer-icp:hover {
  color: var(--color-gold-light);
  border-bottom-color: var(--color-gold-light);
}

/* ==========================================================================
   Reveal on scroll（JS 添加 .is-visible）
   ========================================================================== */

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--duration-slow) var(--ease-out), transform var(--duration-slow) var(--ease-out);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

.hero-copy {
  transition-delay: 0.05s;
}

.hero-visual {
  transition-delay: 0.18s;
}

.about .section-body,
.contact .contact-list {
  transition-delay: 0.1s;
}

.cap-item:nth-child(2) {
  transition-delay: 0.06s;
}

.cap-item:nth-child(3) {
  transition-delay: 0.12s;
}

.cap-item:nth-child(4) {
  transition-delay: 0.18s;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr 0.85fr;
    gap: 3rem;
  }

  .cap-item {
    grid-template-areas:
      "num name"
      ".   desc";
    grid-template-columns: 4.5rem minmax(0, 1fr);
    row-gap: 0.7rem;
  }
}

@media (max-width: 767px) {
  .container {
    width: min(100% - 2rem, 1160px);
  }

  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.5rem 1.25rem 1.25rem;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-line);
    box-shadow: 0 20px 32px -24px rgba(20, 34, 56, 0.35);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity var(--duration-mid) var(--ease-out), transform var(--duration-mid) var(--ease-out), visibility 0s linear var(--duration-mid);
  }

  .site-nav.is-open .nav-menu {
    opacity: 1;
    visibility: visible;
    transform: none;
    transition: opacity var(--duration-mid) var(--ease-out), transform var(--duration-mid) var(--ease-out);
  }

  .nav-menu li {
    border-bottom: 1px solid var(--color-line);
  }

  .nav-menu li:last-child {
    border-bottom: 0;
  }

  .nav-menu a {
    display: block;
    padding: 1rem 0.2rem;
    font-size: 1.05rem;
  }

  .nav-menu a::after {
    display: none;
  }

  .hero {
    padding-top: clamp(3.5rem, 12vw, 5rem);
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3.25rem;
  }

  .hero-title {
    font-size: clamp(2.35rem, 11vw, 3rem);
  }

  .hero-sub {
    margin-top: 1.4rem;
  }

  .hero-actions {
    margin-top: 2.25rem;
  }

  .btn {
    flex: 1 1 auto;
    justify-content: center;
  }

  .brand-tile {
    width: min(250px, 100%);
  }

  .brand-tile-logo {
    height: 64px;
    width: auto;
  }

  .about-grid,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .about-values {
    gap: 1.75rem;
  }

  .cap-item {
    padding: 1.6rem 0;
  }

  .cap-item:hover {
    padding-left: 0;
  }

  .cap-item:hover .cap-name {
    transform: none;
  }

  .contact-row {
    grid-template-columns: 1fr;
    gap: 0.4rem;
    padding: 1.25rem 0;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 2.25rem 0 2.5rem;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }
}