/* ============================================================
   RyboTech Design System · 高端工业制造 + 现代科技感
   ============================================================ */
/* Google Fonts loaded via <link> in HTML head for performance */

/* --- Tokens --- */
:root {
  /* Brand color ramp */
  --ink-950: #051620;
  --ink-900: #071C2A;
  --ink-800: #0A2438;
  --ink-700: #10324B;
  --steel-600: #1C4A63;
  --steel-500: #2E6379;
  --air-600: #0A6E96;
  --air-500: #0E8FBF;
  --air-400: #27A8D2;
  --air-300: #7FD0E6;
  --air-100: #E3F3F8;
  --signal-600: #A96F1F;
  --signal-500: #C8862E;
  --signal-100: #F6EAD8;

  /* Semantic tokens (kept for existing component classes) */
  --c-primary: var(--ink-800);
  --c-primary-dark: var(--ink-900);
  --c-primary-light: var(--steel-600);
  --c-accent: var(--air-600);
  --c-accent-light: var(--air-300);
  --c-accent-glow: rgba(10, 110, 150, 0.12);
  --c-cta: var(--signal-500);
  --c-cta-hover: var(--signal-600);
  --c-success: #1F8A5B;
  --c-warning: #C07A12;

  /* Neutrals */
  --c-text: #12263A;
  --c-text-light: #3E5568;
  --c-text-muted: #4D6376;
  --c-bg: #FFFFFF;
  --c-bg-alt: #F2F5F8;
  --c-bg-dark: var(--ink-900);
  --c-border: #D8E1E8;
  --c-border-dark: rgba(255, 255, 255, 0.12);

  /* Typography */
  --font-display: "Archivo", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Consolas", monospace;

  /* Spacing */
  --sp-xs: 0.25rem;
  --sp-sm: 0.5rem;
  --sp-md: 1rem;
  --sp-lg: 2rem;
  --sp-xl: 4rem;
  --sp-2xl: 6rem;

  /* Layout */
  --container: 1200px;
  --header-h: 76px;
  --radius: 6px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 0 var(--c-border);
  --shadow-md: 0 6px 16px rgba(5, 22, 32, 0.10);

  /* Motion */
  --t-fast: 0.16s cubic-bezier(0.4, 0, 0.2, 1);
  --t-base: 0.32s cubic-bezier(0.33, 1, 0.68, 1);
  --t-slow: 0.6s cubic-bezier(0.33, 1, 0.68, 1);
}

/* --- Reset & Base --- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-sans);
  color: var(--c-text);
  background: var(--c-bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }
::selection { background: var(--air-100); color: var(--ink-800); }
:focus-visible {
  outline: 2px solid var(--air-500);
  outline-offset: 3px;
  border-radius: 2px;
}

/* --- Container --- */
.container { max-width: var(--container); margin: 0 auto; padding: 0 1.5rem; }
.container-wide { max-width: 1400px; margin: 0 auto; padding: 0 1.5rem; }

/* --- Section --- */
.section { padding: clamp(4rem, 8vw, 7rem) 0; }
.section-sm { padding: clamp(2.5rem, 5vw, 4rem) 0; }
.section-alt { background: var(--c-bg-alt); }
.section-dark { background: var(--c-bg-dark); color: #C8D8E8; }

/* Anchor scroll offset for fixed header */
[id] { scroll-margin-top: calc(var(--header-h) + 1rem); }

/* --- Typography --- */
.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 700;
  color: var(--ink-800);
  text-align: center;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
  text-wrap: balance;
}
.section-dark .section-title { color: #FFFFFF; }
.section-subtitle {
  text-align: center;
  color: var(--c-text-light);
  font-size: 1.02rem;
  margin-bottom: clamp(2.5rem, 5vw, 4rem);
  max-width: 660px;
  margin-left: auto;
  margin-right: auto;
  text-wrap: pretty;
}
.section-dark .section-subtitle { color: #9DB4C4; }

/* Kicker used sparingly (hero / intro only) */
.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--c-accent);
  margin-bottom: 1rem;
}
.section-tag::before,
.section-tag::after {
  content: '';
  height: 1px;
  width: 26px;
  background: currentColor;
  opacity: 0.45;
}

/* --- Header --- */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  z-index: 1000;
  transition: border-color var(--t-base), background var(--t-base);
}
.header.scrolled {
  border-bottom-color: var(--c-border);
  background: rgba(255, 255, 255, 0.97);
}
.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.logo { display: flex; align-items: center; gap: 0.7rem; }
.logo-mark {
  width: auto;
  height: 36px;
  aspect-ratio: 4.86 / 1;
  flex-shrink: 0;
}
.logo-stack {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
  gap: 2px;
}
.logo-text {
  font-family: var(--font-display);
  font-size: 1.22rem;
  font-weight: 700;
  color: var(--ink-800);
  letter-spacing: -0.01em;
  line-height: 1;
}
.logo-text span { color: var(--c-accent); }
.logo-sub { font-size: 0.68rem; color: var(--c-text-muted); letter-spacing: 0.08em; }
.logo-tagline {
  font-family: var(--font-display);
  font-size: 0.56rem;
  font-weight: 700;
  color: var(--c-accent);
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

/* --- Nav --- */
.nav { display: flex; align-items: center; gap: 0.15rem; flex-wrap: nowrap; }
.nav a {
  position: relative;
  padding: 0.55rem 0.75rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--c-text);
  white-space: nowrap;
  transition: color var(--t-fast);
}
.nav a::after {
  content: '';
  position: absolute;
  left: 0.75rem; right: 0.75rem; bottom: 0.28rem;
  height: 2px;
  background: var(--c-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-base);
}
.nav a:hover { color: var(--c-accent); }
.nav a:hover::after,
.nav a.active::after { transform: scaleX(1); }
.nav a.active { color: var(--ink-800); font-weight: 600; }

.header-actions { display: flex; align-items: center; gap: 0.8rem; flex-shrink: 0; }
.hotline, .lang-toggle, .header-actions .btn { white-space: nowrap; }
.lang-toggle {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--c-text-light);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 0.32rem 0.62rem;
  cursor: pointer;
  transition: all var(--t-fast);
}
.lang-toggle:hover { border-color: var(--c-accent); color: var(--c-accent); }
.hotline {
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--ink-800);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.hotline::before {
  content: '';
  width: 14px;
  height: 14px;
  background: var(--c-accent);
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6.62 10.79a15.05 15.05 0 0 0 6.59 6.59l2.2-2.2a1 1 0 0 1 1.02-.24c1.12.37 2.33.57 3.57.57a1 1 0 0 1 1 1V20a1 1 0 0 1-1 1C10.85 21 3 13.15 3 4a1 1 0 0 1 1-1h3.5a1 1 0 0 1 1 1c0 1.24.2 2.45.57 3.57a1 1 0 0 1-.24 1.02l-2.21 2.2z'/%3E%3C/svg%3E") center / contain no-repeat;
          mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6.62 10.79a15.05 15.05 0 0 0 6.59 6.59l2.2-2.2a1 1 0 0 1 1.02-.24c1.12.37 2.33.57 3.57.57a1 1 0 0 1 1 1V20a1 1 0 0 1-1 1C10.85 21 3 13.15 3 4a1 1 0 0 1 1-1h3.5a1 1 0 0 1 1 1c0 1.24.2 2.45.57 3.57a1 1 0 0 1-.24 1.02l-2.21 2.2z'/%3E%3C/svg%3E") center / contain no-repeat;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.72rem 1.6rem;
  font-family: var(--font-sans);
  font-size: 0.92rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--t-fast), color var(--t-fast), border-color var(--t-fast), transform var(--t-fast);
}
.btn-primary {
  background: var(--ink-800);
  color: #fff;
}
.btn-primary:hover {
  background: var(--ink-700);
  transform: translateY(-2px);
}
.btn-cta {
  background: var(--ink-800);
  color: #fff;
}
.btn-cta:hover {
  background: var(--ink-700);
  transform: translateY(-2px);
}
.btn-outline {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.55);
}
.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #fff;
}
.btn-dark {
  background: var(--ink-800);
  color: #fff;
}
.btn-dark:hover {
  background: var(--ink-700);
  transform: translateY(-2px);
}
.btn-lg { padding: 0.95rem 2.2rem; font-size: 1rem; }
.btn-sm { padding: 0.52rem 1.15rem; font-size: 0.85rem; }
.header .btn-cta {
  background: transparent;
  color: var(--ink-800);
  border-color: var(--ink-800);
}
.header .btn-cta:hover {
  background: var(--ink-800);
  color: #fff;
}
.hero .btn-primary {
  background: var(--air-400);
  color: var(--ink-950);
}
.hero .btn-primary:hover {
  background: var(--air-300);
}
.cta-banner .btn-cta {
  background: var(--air-400);
  color: var(--ink-950);
}
.cta-banner .btn-cta:hover {
  background: var(--air-300);
}

/* --- Hero --- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: var(--header-h);
}
.hero-bg { position: absolute; inset: 0; z-index: 0; overflow: hidden; }
.hero-bg-img {
  position: absolute; inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0;
  transition: opacity 1.2s ease;
  z-index: 1;
  will-change: transform;
}
.hero-bg-img.active { opacity: 1; animation: kenburns 18s ease-out forwards; }
@keyframes kenburns {
  from { transform: scale(1); }
  to { transform: scale(1.06); }
}
.hero-bg-img::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    linear-gradient(100deg, rgba(4, 14, 22, 0.92) 0%, rgba(7, 28, 42, 0.78) 48%, rgba(10, 36, 56, 0.42) 100%);
  z-index: 2;
}
.hero-pattern {
  position: absolute;
  inset: 0;
  opacity: 0.09;
  z-index: 3;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='360' height='120' viewBox='0 0 360 120'%3E%3Cg fill='none' stroke='%23FFFFFF' stroke-width='1'%3E%3Cpath d='M 40 40 H 300'/%3E%3Cpath d='M 70 60 H 310'/%3E%3Cpath d='M 100 80 H 320'/%3E%3C/g%3E%3C/svg%3E");
  background-size: 360px 120px;
}
.hero-content { position: relative; z-index: 5; color: #fff; max-width: 700px; }
.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-family: var(--font-display);
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--air-300);
  margin-bottom: 1.6rem;
}
.hero-tag::before {
  content: '';
  width: 34px;
  height: 1px;
  background: var(--air-400);
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5.4vw, 4.4rem);
  font-weight: 800;
  line-height: 1.14;
  margin-bottom: 1.3rem;
  letter-spacing: -0.02em;
  text-wrap: balance;
}
.hero h1 .accent { color: var(--air-300); }
.hero-desc {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.82);
  line-height: 1.9;
  margin-bottom: 2.2rem;
  max-width: 560px;
  text-wrap: pretty;
}
.hero-actions { display: flex; gap: 1rem; flex-wrap: wrap; }

.hero-slides { position: relative; }
.hero-slide { display: none; }
.hero-slide.active { display: block; animation: heroIn 0.7s var(--t-base) both; }
@keyframes heroIn {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: translateY(0); }
}
.hero-dots { display: flex; gap: 0.6rem; margin-top: 2.6rem; }
.hero-dot {
  width: 30px;
  height: 3px;
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.25);
  cursor: pointer;
  transition: all var(--t-base);
  border: 0;
  padding: 0;
  -webkit-appearance: none;
  appearance: none;
}
.hero-dot.active { background: var(--air-400); width: 46px; }

/* Hero engineering-data strip */
.hero-stats {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  z-index: 4;
  background: rgba(4, 14, 22, 0.78);
  backdrop-filter: blur(10px);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.hero-stats-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 1.3rem 1.5rem;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}
.stat-item {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  border-left: 1px solid rgba(255, 255, 255, 0.14);
  padding-left: 1.2rem;
}
.stat-num {
  font-family: var(--font-display);
  font-size: 1.9rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.stat-num .unit { font-size: 1rem; color: var(--air-300); }
.stat-label { font-size: 0.8rem; color: rgba(255, 255, 255, 0.62); }

/* --- Page Hero (sub-pages) --- */
.page-hero {
  position: relative;
  padding: calc(var(--header-h) + 4.5rem) 0 4.5rem;
  background: var(--ink-900);
  color: #fff;
  overflow: hidden;
}
.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(110deg, rgba(4, 14, 22, 0.55) 0%, rgba(7, 28, 42, 0.35) 100%);
}
.page-hero .hero-pattern { opacity: 0.07; }
.page-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3.6vw, 2.9rem);
  font-weight: 800;
  margin-bottom: 0.9rem;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.page-hero p {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.78);
  max-width: 640px;
  line-height: 1.85;
}
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.82rem;
  margin-bottom: 1.2rem;
  color: rgba(255, 255, 255, 0.5);
}
.breadcrumb a:hover { color: var(--air-300); }
.breadcrumb span { color: rgba(255, 255, 255, 0.85); }

/* --- Product Cards --- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}
.product-card {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform var(--t-base), border-color var(--t-base);
}
.product-card:hover {
  transform: translateY(-6px);
  border-color: var(--steel-500);
}
.product-card-img {
  height: 190px;
  position: relative;
  display: flex;
  align-items: flex-end;
  padding: 1rem 1.25rem;
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: #fff;
  overflow: hidden;
  background-size: cover;
  background-position: center;
}
.product-card-img::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 22, 32, 0.15) 0%, rgba(5, 22, 32, 0.78) 100%);
  z-index: 0;
}
.product-card-img::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, var(--air-600), transparent 65%);
  opacity: 0;
  mix-blend-mode: soft-light;
  transition: opacity var(--t-base);
  z-index: 0;
}
.product-card:hover .product-card-img::after { opacity: 1; }
.product-card-img span { position: relative; z-index: 1; text-shadow: 0 1px 8px rgba(0, 0, 0, 0.35); }
.product-card-body {
  padding: 1.4rem 1.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}
.product-card-body h3 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--ink-800);
  margin-bottom: 0.3rem;
  line-height: 1.4;
}
.product-card-body .product-code {
  font-family: var(--font-display);
  font-size: 0.76rem;
  font-weight: 600;
  color: var(--c-accent);
  letter-spacing: 0.08em;
  margin-bottom: 0.7rem;
}
.product-card-body p {
  font-size: 0.88rem;
  color: var(--c-text-light);
  line-height: 1.7;
  flex: 1;
}
.product-card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 1rem;
}
.product-tag {
  font-size: 0.74rem;
  padding: 0.22rem 0.6rem;
  background: var(--c-bg-alt);
  color: var(--c-text-light);
  border: 1px solid var(--c-border);
  border-radius: 4px;
  font-weight: 500;
}

/* --- Feature Cards --- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
}
.feature-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 1.8rem;
  border: 1px solid var(--c-border);
  transition: transform var(--t-base), border-color var(--t-base);
}
.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--steel-500);
}
.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  margin-bottom: 1rem;
  background: var(--air-100);
  color: var(--c-accent);
}
.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink-800);
  margin-bottom: 0.5rem;
}
.feature-card p { font-size: 0.88rem; color: var(--c-text-light); line-height: 1.7; }

/* --- Solution Cards (index) --- */
.solution-scroll-wrapper {
  overflow-x: auto;
  overflow-y: hidden;
  margin: 0 -1rem;
  padding: 0.25rem 1rem 1.25rem;
  -webkit-overflow-scrolling: touch;
  scroll-snap-type: x mandatory;
}
.solution-scroll-wrapper::-webkit-scrollbar { height: 4px; }
.solution-scroll-wrapper::-webkit-scrollbar-track { background: rgba(10, 36, 56, 0.08); }
.solution-scroll-wrapper::-webkit-scrollbar-thumb { background: var(--steel-500); border-radius: 2px; }
.solution-grid {
  display: flex;
  gap: 1.5rem;
  width: max-content;
}
.solution-card {
  flex: 0 0 330px;
  scroll-snap-align: start;
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  cursor: pointer;
  transition: transform var(--t-base);
  background: var(--ink-800);
  min-height: 360px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
}
.solution-card:hover { transform: translateY(-6px); }
.solution-card-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  opacity: 0.9;
  background-size: cover;
  background-position: center;
  transition: transform 0.9s var(--t-base);
}
.solution-card:hover .solution-card-bg { transform: scale(1.04); }
.solution-card-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 22, 32, 0.25) 0%, rgba(5, 22, 32, 0.94) 100%);
}
.solution-card-content {
  position: relative;
  z-index: 1;
  padding: 1.5rem;
  color: #fff;
}
.solution-card-content h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
  line-height: 1.4;
}
.solution-card-content p {
  font-size: 0.86rem;
  color: rgba(255, 255, 255, 0.78);
  line-height: 1.65;
}
.solution-card .arrow {
  position: absolute;
  top: 1.4rem;
  right: 1.4rem;
  z-index: 1;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 50%;
  font-size: 1rem;
  transition: background var(--t-base), transform var(--t-base), border-color var(--t-base);
}
.solution-card:hover .arrow {
  background: var(--air-400);
  border-color: var(--air-400);
  transform: rotate(45deg);
}

/* --- Why RyboTech --- */
.why-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 1.5rem;
}
.why-card {
  padding: 1.9rem 1.6rem;
  border-radius: var(--radius-lg);
  background: #fff;
  border: 1px solid var(--c-border);
  transition: transform var(--t-base), border-color var(--t-base);
}
.why-card:hover {
  transform: translateY(-4px);
  border-color: var(--steel-500);
}
.why-num { display: none; }
.why-card h3 {
  position: relative;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink-800);
  margin-bottom: 0.6rem;
  padding-top: 0.8rem;
}
.why-card h3::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--air-500);
}
.why-card p { font-size: 0.88rem; color: var(--c-text-light); line-height: 1.7; }

/* --- Cases (index) --- */
.case-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 1.5rem;
}
.case-card {
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #fff;
  border: 1px solid var(--c-border);
  transition: transform var(--t-base), border-color var(--t-base);
}
.case-card:hover {
  transform: translateY(-5px);
  border-color: var(--steel-500);
}
.case-card-img {
  height: 230px;
  display: flex;
  align-items: flex-end;
  padding: 1.2rem;
  font-family: var(--font-display);
  font-size: 1.1rem;
  color: #fff;
  font-weight: 600;
  position: relative;
  background-size: cover;
  background-position: center;
}
.case-card-img::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 22, 32, 0.05) 40%, rgba(5, 22, 32, 0.82) 100%);
}
.case-card-img span { position: relative; z-index: 1; text-shadow: 0 1px 8px rgba(0, 0, 0, 0.3); }
.case-card-body { padding: 1.5rem; }
.case-card-body .case-tag {
  font-family: var(--font-display);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--c-accent);
  margin-bottom: 0.45rem;
  text-transform: uppercase;
}
.case-card-body h3 {
  font-size: 1.04rem;
  font-weight: 700;
  color: var(--ink-800);
  margin-bottom: 0.55rem;
  line-height: 1.45;
}
.case-card-body p { font-size: 0.88rem; color: var(--c-text-light); line-height: 1.7; }
.case-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 1.1rem;
  padding-top: 1.1rem;
  border-top: 1px solid var(--c-border);
}
.case-stat-num {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--air-600);
  line-height: 1.1;
}
.case-stat-label { font-size: 0.76rem; color: var(--c-text-muted); }

/* --- CTA Banner --- */
.cta-banner {
  position: relative;
  background: var(--ink-900);
  border-radius: var(--radius-lg);
  padding: clamp(2.5rem, 6vw, 4.5rem);
  text-align: center;
  color: #fff;
  overflow: hidden;
}
.cta-banner::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--air-400), var(--air-600));
}
.cta-banner h2 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3.2vw, 2.1rem);
  font-weight: 700;
  margin-bottom: 0.8rem;
  position: relative;
  letter-spacing: -0.01em;
}
.cta-banner p {
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 1.8rem;
  position: relative;
  font-size: 1rem;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}
.cta-banner .btn { position: relative; }

/* --- Footer --- */
.footer {
  background: var(--ink-950);
  color: #8FA6B5;
  padding: 4.5rem 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2.2fr 1fr 1fr 1fr 1.4fr;
  gap: 2rem;
  margin-bottom: 3rem;
}
.footer-brand .logo-text { color: #fff; }
.footer-brand .logo-mark { width: auto; height: 40px; aspect-ratio: 4.86 / 1; }
.footer-brand .logo-sub { color: rgba(143, 166, 181, 0.7); }
.footer-brand .logo-tagline { color: var(--air-300); }
.footer-brand p {
  font-size: 0.86rem;
  line-height: 1.8;
  margin-top: 1.2rem;
  max-width: 300px;
  color: rgba(143, 166, 181, 0.85);
}
.footer-brand .footer-slogan {
  margin-top: 1rem;
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--air-300);
  letter-spacing: 0.06em;
}
.footer-col h4 {
  color: #fff;
  font-size: 0.92rem;
  font-weight: 600;
  margin-bottom: 1.1rem;
  letter-spacing: 0.04em;
}
.footer-col ul li { margin-bottom: 0.55rem; }
.footer-col ul li a {
  font-size: 0.86rem;
  color: rgba(143, 166, 181, 0.9);
  transition: color var(--t-fast);
}
.footer-col ul li a:hover { color: var(--air-300); }
.footer-contact li {
  font-size: 0.86rem;
  margin-bottom: 0.65rem;
  display: flex;
  gap: 0.55rem;
  align-items: flex-start;
}
.footer-contact .icon { color: var(--air-400); flex-shrink: 0; }
.footer-bottom {
  border-top: 1px solid var(--c-border-dark);
  padding: 1.5rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: rgba(143, 166, 181, 0.75);
}
.footer-bottom a:hover { color: var(--air-300); }
.qr-code {
  width: 92px;
  height: 92px;
  background: #fff;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 0.7rem;
  font-size: 0.68rem;
  color: var(--c-text-muted);
  border: 1px solid rgba(255, 255, 255, 0.15);
  overflow: hidden;
  padding: 0;
}
.qr-code img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

/* --- Mobile Menu --- */
.menu-toggle {
  display: none;
  font-size: 1.4rem;
  cursor: pointer;
  color: var(--ink-800);
  background: none;
  border: 0;
  padding: 0.35rem;
  line-height: 1;
}
.mobile-nav { display: none; }

/* --- Utility --- */
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.mb-2 { margin-bottom: 2rem; }
.flex-center { display: flex; align-items: center; justify-content: center; }

/* --- Reveal --- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }
.product-grid .reveal:nth-child(2),
.feature-grid .reveal:nth-child(2),
.why-grid .reveal:nth-child(2) { transition-delay: 0.05s; }
.product-grid .reveal:nth-child(3),
.feature-grid .reveal:nth-child(3),
.why-grid .reveal:nth-child(3) { transition-delay: 0.1s; }
.product-grid .reveal:nth-child(4),
.feature-grid .reveal:nth-child(4),
.why-grid .reveal:nth-child(4) { transition-delay: 0.15s; }
.product-grid .reveal:nth-child(5),
.feature-grid .reveal:nth-child(5),
.why-grid .reveal:nth-child(5) { transition-delay: 0.2s; }
.product-grid .reveal:nth-child(6),
.feature-grid .reveal:nth-child(6),
.why-grid .reveal:nth-child(6) { transition-delay: 0.25s; }

/* --- Responsive --- */
@media (max-width: 1100px) {
  .nav { display: none; }
  .menu-toggle { display: block; }
  .hero-stats-inner { grid-template-columns: repeat(2, 1fr); gap: 1.2rem 2rem; }
}
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 1.5rem; }
  .hero h1 { font-size: clamp(2.2rem, 6vw, 3.2rem); }
}
@media (max-width: 768px) {
  .header-actions .hotline,
  .header-actions .lang-toggle { display: none; }
  .section { padding: 3.2rem 0; }
  .hero { min-height: 100svh; }
  .hero-desc { font-size: 1rem; }
  .section-title { font-size: 1.5rem; }
  .hero-stats-inner { grid-template-columns: repeat(2, 1fr); padding: 1.1rem 1.5rem; }
  .stat-item { padding-left: 0.9rem; }
  .stat-num { font-size: 1.5rem; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 0.5rem; text-align: center; }
  .cta-banner { padding: 2rem 1.4rem; }
  .cta-banner h2 { font-size: 1.4rem; }
  .page-hero h1 { font-size: 1.8rem; }
  .page-hero { padding-top: calc(var(--header-h) + 3rem); }
  .case-card-img { height: 200px; }

  .mobile-nav {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0; bottom: 0;
    background: rgba(255, 255, 255, 0.98);
    z-index: 999;
    padding: 1.2rem 1.5rem 3rem;
    transform: translateX(100%);
    transition: transform var(--t-base);
    overflow-y: auto;
  }
  .mobile-nav.open { transform: translateX(0); }
  .mobile-nav a {
    display: block;
    padding: 1rem 0;
    font-size: 1.05rem;
    font-weight: 500;
    border-bottom: 1px solid var(--c-border);
    color: var(--c-text);
  }
  .mobile-nav a.active { color: var(--c-accent); font-weight: 600; }
  .mobile-nav a:hover { color: var(--c-accent); }
}
@media (max-width: 480px) {
  .logo-mark { width: auto; height: 30px; aspect-ratio: 4.86 / 1; }
  .footer-brand .logo-mark { height: 32px; }
  .logo-text { font-size: 1.05rem; }
  .header-actions .btn-sm { padding: 0.45rem 0.9rem; font-size: 0.8rem; }
  .hero h1 { font-size: 2rem; }
  .hero-stats-inner { gap: 1rem 1.2rem; }
  .case-stats { grid-template-columns: 1fr; }
}

/* --- Reduced Motion --- */
@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;
  }
  .reveal { opacity: 1; transform: none; }
  .hero-bg-img.active { animation: none; }
}