/* ============================================================
   SHANGQU.AI — International website
   Design tokens: folded-peak signature, violet + sky from logo,
   light high-key surfaces, engineered grid.
   ============================================================ */

:root {
  --violet: #6C49E0;
  --violet-deep: #4A2EBD;
  --violet-ink: #1B1440;
  --sky: #64B5E8;
  --sky-deep: #2E8FD0;

  --ink: #191536;
  --muted: #5B5772;
  --faint: #8B88A0;

  --bg: #FBFBFE;
  --bg-alt: #F4F4FB;
  --line: #E6E4F2;
  --card: #FFFFFF;

  --accent: var(--violet);
  --accent-deep: var(--violet-deep);
  --accent-soft: rgba(108, 73, 224, 0.08);
  --accent-tint: #F1EDFC;

  --radius: 14px;
  --radius-sm: 10px;
  --pad: 104px;
  --header-h: 72px;

  --font-display: "Space Grotesk", "IBM Plex Sans", sans-serif;
  --font-body: "IBM Plex Sans", -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;

  --shadow-card: 0 1px 2px rgba(27, 20, 64, 0.04), 0 12px 32px -16px rgba(27, 20, 64, 0.14);
  --shadow-hover: 0 2px 4px rgba(27, 20, 64, 0.05), 0 24px 48px -20px rgba(27, 20, 64, 0.22);
}

/* Tweak variants */
html[data-accent="天青蓝"] {
  --accent: var(--sky-deep);
  --accent-deep: #1F78B4;
  --accent-soft: rgba(100, 181, 232, 0.14);
  --accent-tint: #E8F4FC;
}
html[data-density="紧凑"] { --pad: 64px; }

/* ---------- base ---------- */

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
}

section[id] { scroll-margin-top: calc(var(--header-h) + 16px); }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 15px;
  line-height: 1;
  padding: 15px 26px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.15s ease, color 0.2s ease;
}
.btn svg { width: 15px; height: 15px; }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover { background: var(--accent-deep); }

.btn-ghost {
  color: var(--ink);
  border-color: var(--line);
  background: transparent;
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

.btn-sm { padding: 10px 18px; font-size: 14px; }

.btn-white {
  background: #fff;
  color: var(--violet-ink);
}
.btn-white:hover { background: var(--accent-tint); }

.btn-outline {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.4);
}
.btn-outline:hover { border-color: #fff; background: rgba(255, 255, 255, 0.1); }

/* ---------- eyebrow & headings ---------- */

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}

.peak { width: 15px; height: 15px; }
.peak path {
  fill: none;
  stroke-width: 2.4;
  stroke-linecap: round;
}
.peak-l { stroke: var(--sky); }
.peak-r { stroke: var(--violet); }

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.015em;
  line-height: 1.12;
  color: var(--ink);
  text-wrap: balance;
}

h2 { font-size: clamp(30px, 3.6vw, 44px); }

.lede {
  color: var(--muted);
  font-size: 17px;
  max-width: 620px;
  margin-top: 14px;
}

.mono-tag {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(251, 251, 254, 0.86);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}
.site-header.scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 8px 24px -20px rgba(27, 20, 64, 0.25);
}

.header-inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

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

.main-nav {
  display: flex;
  gap: 30px;
}
.main-nav a {
  font-size: 14.5px;
  font-weight: 500;
  color: var(--muted);
  transition: color 0.2s ease;
  position: relative;
}
.main-nav a:hover { color: var(--ink); }
.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: -6px;
  height: 2px;
  background: linear-gradient(90deg, var(--sky), var(--violet));
  transition: right 0.25s ease;
}
.main-nav a:hover::after { right: 0; }

.header-actions {
  display: flex;
  align-items: center;
  gap: 20px;
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12.5px;
}
.lang {
  background: none;
  border: none;
  padding: 0;
  font: inherit;
  font-family: var(--font-mono);
  color: var(--faint);
  cursor: pointer;
  transition: color 0.2s ease;
}
.lang.active { color: var(--accent); font-weight: 500; }
.lang:hover { color: var(--ink); }
.lang-sep {
  width: 1px;
  height: 12px;
  background: var(--line);
}

/* 语言切换仅在展开的移动菜单中显示 */
.mobile-lang { display: none; }

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: transparent;
  cursor: pointer;
  padding: 0 11px;
}
.menu-toggle span {
  display: block;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.menu-toggle.open span:first-child { transform: translateY(4px) rotate(45deg); }
.menu-toggle.open span:last-child { transform: translateY(-4px) rotate(-45deg); }

/* ---------- hero ---------- */

.hero {
  position: relative;
  padding: 96px 0 0;
  overflow: hidden;
  background:
    radial-gradient(900px 520px at 82% 8%, rgba(108, 73, 224, 0.10), transparent 62%),
    radial-gradient(700px 460px at 6% 90%, rgba(100, 181, 232, 0.12), transparent 60%),
    linear-gradient(180deg, #FFFFFF 0%, var(--bg) 100%);
}

.hero-fold-bg {
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    115deg,
    transparent 0px,
    transparent 220px,
    rgba(108, 73, 224, 0.035) 220px,
    rgba(108, 73, 224, 0.035) 221px
  );
  pointer-events: none;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 64px;
  align-items: center;
}

.hero-copy h1 {
  font-size: clamp(40px, 5.2vw, 64px);
  font-weight: 700;
  margin-bottom: 22px;
}
.hero-copy h1 em {
  font-style: normal;
  background: linear-gradient(100deg, var(--violet) 20%, var(--sky-deep) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.hero-copy .lede { font-size: 18px; }

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.hero-note {
  margin-top: 22px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--faint);
}

/* hero visual with folded corner — the brand’s folded-A signature */
.hero-figure {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--line);
}
.hero-figure img {
  width: 100%;
  aspect-ratio: 4 / 4.4;
  object-fit: cover;
  object-position: top center;
}

.fold-corner {
  position: absolute;
  top: 0;
  right: 0;
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 0 56px 56px 0;
  border-color: transparent var(--accent) transparent transparent;
  opacity: 0.92;
}
.fold-corner::after {
  content: "";
  position: absolute;
  top: 0;
  left: 1px;
  border-style: solid;
  border-width: 0 50px 50px 0;
  border-color: transparent rgba(255, 255, 255, 0.85) transparent transparent;
}

.spec-chip {
  position: absolute;
  display: flex;
  flex-direction: column;
  gap: 1px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(6px);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 8px 12px;
  box-shadow: 0 6px 18px -10px rgba(27, 20, 64, 0.25);
}
.spec-chip strong {
  font-family: var(--font-display);
  font-size: 13.5px;
  color: var(--ink);
  letter-spacing: 0;
}
.chip-a { top: 22px; left: -14px; }
.chip-b { bottom: 96px; left: -10px; }
.chip-c { bottom: 22px; right: 18px; }

/* stats */
.stats-band {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: 80px;
  padding: 34px 0 56px;
  border-top: 1px solid var(--line);
}
.stat { display: flex; flex-direction: column; gap: 6px; padding-right: 24px; }
.stat + .stat { border-left: 1px solid var(--line); padding-left: 32px; }
.stat-value {
  font-family: var(--font-display);
  font-size: 40px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}
.stat-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--faint);
}

/* ---------- sections ---------- */

.section { padding: var(--pad) 0; }
.section-alt { background: var(--bg-alt); }

.section-head { margin-bottom: 56px; }
.section-head .lede { margin-top: 16px; }

/* ---------- products ---------- */

.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.product-card {
  display: flex;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}
.product-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-4px);
}

.product-media {
  position: relative;
  flex: 0 0 38%;
  min-height: 300px;
}
.product-media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.product-body {
  flex: 1;
  padding: 30px 32px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 10px;
}
.product-body h3 { font-size: 27px; }
.product-body > p { color: var(--muted); font-size: 15px; }

.spec-list {
  list-style: none;
  margin-top: 8px;
  width: 100%;
}
.spec-list li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 8px 0;
  border-top: 1px solid var(--line);
}
.spec-list li:first-child { border-top: 0; }
.spec-list .spec-k {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 500;
  color: var(--accent);
  min-width: 74px;
  font-variant-numeric: tabular-nums;
}
.spec-list .spec-v {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--faint);
  text-transform: uppercase;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin-top: auto;
  padding-top: 14px;
  font-family: var(--font-display);
  font-size: 14.5px;
  font-weight: 500;
  color: var(--accent);
  transition: gap 0.2s ease;
}
.card-link svg { width: 14px; height: 14px; }
.card-link:hover { gap: 11px; }

.product-note {
  margin-top: 40px;
  max-width: 860px;
  font-size: 14.5px;
  color: var(--muted);
  border-left: 3px solid var(--accent);
  padding-left: 16px;
}

/* ---------- i18n typography ---------- */

html[lang="zh-CN"] body {
  font-family: "IBM Plex Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}
html[lang="zh-CN"] h1,
html[lang="zh-CN"] h2,
html[lang="zh-CN"] h3,
html[lang="zh-CN"] .statement,
html[lang="zh-CN"] .shen-text,
html[lang="zh-CN"] .vmv p {
  font-family: "Space Grotesk", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

/* ---------- challenges ---------- */

.challenge-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
}

.challenge-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 26px 24px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.challenge-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.challenge-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.challenge-card h3::before {
  content: "";
  width: 11px;
  height: 11px;
  flex: none;
  transform: translateY(-1px);
  background: linear-gradient(135deg, var(--sky) 50%, var(--violet) 50%);
  clip-path: polygon(0 0, 100% 0, 50% 100%);
}
.challenge-card p { font-size: 14px; color: var(--muted); }

.statement-band {
  margin-top: 56px;
  text-align: center;
  padding: 0 24px;
}
.statement-peak { width: 22px; height: 22px; margin: 0 auto 18px; display: block; }
.statement {
  font-family: var(--font-display);
  font-size: clamp(20px, 2.4vw, 28px);
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1.5;
  color: var(--ink);
  text-wrap: balance;
  max-width: 900px;
  margin: 0 auto;
}
.statement span {
  background: linear-gradient(100deg, var(--violet) 20%, var(--sky-deep) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* ---------- technology ---------- */

.tech-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
}

.tech-layers { display: flex; flex-direction: column; }

.layer {
  display: flex;
  align-items: center;
  gap: 18px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 15px 20px;
  box-shadow: var(--shadow-card);
  cursor: default;
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.layer:hover {
  border-color: var(--accent);
  transform: translateX(6px);
}
.layer-icon {
  flex: 0 0 46px;
  height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: var(--accent-tint);
  color: var(--accent);
}
.layer-icon svg { width: 24px; height: 24px; }
.layer-text h3 { font-size: 16.5px; margin-bottom: 2px; }
.layer-text p { font-size: 13px; color: var(--muted); line-height: 1.5; }
.layer-tag {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--faint);
}

.layer-link {
  width: 2px;
  height: 14px;
  margin-left: 46px;
  background: linear-gradient(180deg, var(--sky), var(--violet));
  border-radius: 1px;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 36px;
}
.metric {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.metric-value {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 700;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.metric-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--faint);
}

.tech-note {
  margin-top: 26px;
  font-size: 14.5px;
  color: var(--muted);
  border-left: 3px solid var(--accent);
  padding-left: 16px;
}

/* ---------- solutions / tabs ---------- */

.tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}
.tab {
  font-family: var(--font-display);
  font-size: 14.5px;
  font-weight: 500;
  color: var(--muted);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 11px 22px;
  cursor: pointer;
  transition: all 0.2s ease;
}
.tab:hover { border-color: var(--accent); color: var(--ink); }
.tab.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.tab-panel {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
  align-items: center;
}
.tab-panel[hidden] { display: none; }

.tab-media {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
}
.tab-media img { width: 100%; aspect-ratio: 16 / 11; object-fit: cover; }

.tab-body h3 { font-size: clamp(22px, 2.2vw, 28px); margin-bottom: 18px; }

.check-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 26px;
}
.check-list li {
  position: relative;
  padding-left: 28px;
  color: var(--muted);
  font-size: 15.5px;
}
.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 14px;
  height: 14px;
  background:
    linear-gradient(135deg, var(--sky) 50%, var(--violet) 50%);
  clip-path: polygon(0 0, 100% 0, 50% 100%);
}

.result-chips { display: flex; flex-wrap: wrap; gap: 12px; }
.chip {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  background: var(--accent-soft);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 9px 18px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--muted);
}
.chip strong {
  font-family: var(--font-display);
  font-size: 16px;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

/* ---------- trust ---------- */

.cert-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 48px;
}
.cert {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 12px 22px;
  transition: border-color 0.2s ease, color 0.2s ease;
}
.cert:hover { border-color: var(--accent); color: var(--accent); }

.quote-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 44px 46px;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-card);
}
.quote-peak { width: 26px; height: 26px; margin-bottom: 22px; }
.quote-peak path { stroke-width: 2.2; }
.quote-card blockquote {
  font-family: var(--font-display);
  font-size: clamp(19px, 2vw, 26px);
  font-weight: 500;
  line-height: 1.45;
  letter-spacing: -0.01em;
  color: var(--ink);
  max-width: 880px;
  text-wrap: pretty;
}
.quote-card figcaption {
  margin-top: auto;
  padding-top: 28px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.quote-name { font-weight: 600; font-size: 15px; }
.quote-role {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--faint);
}

/* ---------- logo wall ---------- */

.logo-wall {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 14px;
  margin-bottom: 44px;
}

.logo-item {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 20px 14px;
  min-height: 88px;
  transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}
.logo-item img {
  width: 100%;
  max-height: 46px;
  object-fit: contain;
  filter: grayscale(1);
  opacity: 0.62;
  transition: filter 0.25s ease, opacity 0.25s ease;
}
.logo-item:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card);
}
.logo-item:hover img {
  filter: grayscale(0);
  opacity: 1;
}

.capability-wrap { margin-top: 48px; }
.capability-title {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--faint);
  margin-bottom: 16px;
}

/* ---------- about ---------- */

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

.about-figure {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
}
.about-figure img {
  width: 100%;
  aspect-ratio: 4 / 2.8;
  object-fit: cover;
}

.about-meta {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 20px;
}
.about-meta-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.shen-quote {
  margin: 0 0 24px;
  padding: 26px 30px;
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.shen-text {
  font-family: var(--font-display);
  font-size: clamp(19px, 2vw, 24px);
  font-weight: 600;
  line-height: 1.55;
  letter-spacing: 0.02em;
  color: var(--ink);
  text-wrap: balance;
}
.shen-quote cite {
  display: block;
  margin-top: 12px;
  font-style: normal;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--faint);
}

.about-text {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 16px;
  text-wrap: pretty;
}
.about-text strong { color: var(--accent); }

.vmv-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 28px;
}
.vmv {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color 0.2s ease;
}
.vmv:hover { border-color: var(--accent); }
.vmv p {
  font-family: var(--font-display);
  font-size: 14.5px;
  font-weight: 500;
  line-height: 1.55;
  color: var(--ink);
}

/* ---------- delivery methodology ---------- */

.method-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.method-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.method-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.method-card::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -12px;
  width: 8px;
  height: 8px;
  transform: translateY(-50%) rotate(45deg);
  background: linear-gradient(135deg, var(--sky) 50%, var(--violet) 50%);
  z-index: 1;
}
.method-card:last-child::after { display: none; }
.method-num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  margin-bottom: 4px;
}
.method-card h3 {
  font-size: 19px;
  letter-spacing: -0.01em;
}
.method-desc {
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--muted);
  margin-top: 4px;
}

/* ---------- CTA ---------- */

.cta-section { padding-bottom: calc(var(--pad) + 16px); }

.cta-band {
  position: relative;
  overflow: hidden;
  border-radius: 22px;
  padding: 72px 56px;
  text-align: center;
  background:
    radial-gradient(600px 300px at 85% 0%, rgba(100, 181, 232, 0.35), transparent 60%),
    linear-gradient(120deg, var(--violet-ink) 0%, var(--violet-deep) 100%);
  color: #fff;
}
.cta-fold {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 64px 64px 0 0;
  border-color: var(--sky) transparent transparent transparent;
  opacity: 0.85;
}
.cta-band h2 { color: #fff; }
.cta-band p {
  margin: 14px auto 34px;
  max-width: 520px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 16.5px;
}
.cta-band .hero-cta { justify-content: center; margin-top: 0; }

/* ---------- footer ---------- */

.site-footer {
  background: #16112F;
  color: #B9B5D6;
  padding: 72px 0 36px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-logo {
  height: 36px;
  margin-bottom: 18px;
}
.footer-tagline {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 500;
  color: #fff;
  margin-bottom: 18px;
}
.footer-brand address {
  font-style: normal;
  font-size: 13.5px;
  line-height: 1.9;
  color: #8F8AB2;
}
.footer-brand a { color: #B9B5D6; }
.footer-brand a:hover { color: #fff; }

.footer-col { display: flex; flex-direction: column; gap: 12px; }
.footer-col h4 {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #6F6A96;
  margin-bottom: 8px;
  font-weight: 500;
}
.footer-col a {
  font-size: 14.5px;
  color: #B9B5D6;
  transition: color 0.2s ease;
}
.footer-col a:hover { color: #fff; }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
  padding-top: 30px;
  font-size: 13px;
  color: #8F8AB2;
}
.footer-links {
  display: flex;
  align-items: center;
  gap: 20px;
}
.footer-links a { color: #8F8AB2; }
.footer-links a:hover { color: #fff; }
.footer-links .lang-sep { background: rgba(255, 255, 255, 0.2); }
.footer-links .lang {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: #8F8AB2;
}
.footer-links .lang:hover { color: #fff; }
.footer-links .lang.active { color: #fff; }

/* ---------- reveal animation ---------- */

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
  transition-delay: var(--d, 0s);
}
.reveal.in { opacity: 1; transform: none; }

html[data-motion="false"] .reveal {
  opacity: 1;
  transform: none;
  transition: none;
}
html[data-motion="false"] .statement-peak { display: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .statement-peak { display: none; }
}

/* ---------- responsive ---------- */

@media (max-width: 1080px) {
  .hero-grid { gap: 44px; }
  .tech-grid, .about-grid { gap: 44px; }
  .spec-chip { display: none; }
}

@media (max-width: 920px) {
  :root { --pad: 72px; }

  .main-nav {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 24px 40px -24px rgba(27, 20, 64, 0.3);
    padding: 8px 32px 16px;
    display: none;
    max-height: calc(100vh - var(--header-h));
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 13px 0; border-bottom: 1px solid var(--line); }
  .main-nav a::after { display: none; }
  .menu-toggle { display: flex; }
  .lang-switch { display: none; }

  .main-nav .mobile-lang {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 0 4px;
    font-family: var(--font-mono);
    font-size: 13px;
  }
  .main-nav .mobile-lang .lang { padding: 8px 2px; }

  .hero { padding-top: 56px; }
  .hero-grid, .tech-grid, .about-grid, .tab-panel { grid-template-columns: 1fr; }
  .challenge-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .logo-wall { grid-template-columns: repeat(3, 1fr); }
  .method-grid { grid-template-columns: repeat(2, 1fr); }
  .vmv-grid { grid-template-columns: 1fr; }
  .method-card:nth-child(2n)::after { display: none; }
  .hero-figure img { aspect-ratio: 4 / 3.4; }

  /* 移动/平板端：标题 → 技术分层 → 指标 → 注解，避免标题排在层列表之后 */
  .tech-grid { row-gap: 0; }
  .tech-copy { display: contents; }
  .tech-grid .section-head { order: 1; margin-bottom: 36px; }
  .tech-layers { order: 2; }
  .tech-grid .metric-grid { order: 3; }
  .tech-grid .tech-note { order: 4; }

  .stats-band { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0; margin-top: 56px; }
  .stat { padding: 0 16px 0 0; }
  .stat:first-child { padding-left: 0; }
  .stat + .stat { padding-left: 20px; }
  .stat-value { font-size: 32px; }

  .product-grid { grid-template-columns: 1fr; }
  .product-card { flex-direction: column; }
  .product-media { min-height: 240px; flex: none; }
  .product-media img { position: absolute; }

  .product-card { flex-direction: column; }
  .cta-band { padding: 56px 28px; }

  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }
}

@media (max-width: 560px) {
  .container { padding: 0 20px; }
  .header-actions .btn-sm { display: none; }
  .stats-band { grid-template-columns: 1fr; gap: 0; }
  .stat, .stat + .stat { border-left: 0; padding: 18px 0; }
  .stat + .stat { border-top: 1px solid var(--line); }
  .metric-grid { grid-template-columns: 1fr 1fr; }
  .challenge-grid { grid-template-columns: 1fr; }
  .logo-wall { grid-template-columns: 1fr 1fr; }
  .method-grid { grid-template-columns: 1fr; }
  .method-card::after { display: none; }
  .logo-item { min-height: 72px; padding: 14px 10px; }
  .logo-item img { max-height: 38px; }
  .about-meta { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .cta-band .hero-cta { flex-direction: column; align-items: stretch; }
  .cta-band .btn { justify-content: center; }
}

/* 超小屏（iPhone SE / 320px 级别） */
@media (max-width: 380px) {
  .stat-value { font-size: 30px; }
  .stat-label { font-size: 11px; letter-spacing: 0.05em; }
  .challenge-card { padding: 22px 20px; }
  .product-body { padding: 26px 22px; }
}