/* =========================================================
   建峰亿腾科技 — Corporate Site
   Mercury Dark Theme · Vanilla CSS
   ========================================================= */

:root {
  /* Colors */
  --color-mercury-blue: #5266eb;
  --color-ghost-blue: #cdddff;
  --color-deep-space: #171721;
  --color-midnight-slate: #1e1e2a;
  --color-graphite: #272735;
  --color-lead: #70707d;
  --color-starlight: #ededf3;
  --color-silver: #c3c3cc;
  --color-pure-white: #ffffff;

  /* Typography — Font Families (Noto Sans SC for CJK, Inter/Manrope for Latin) */
  --font-display: 'Noto Sans SC', 'Inter', ui-sans-serif, system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-body: 'Manrope', 'Inter', 'Noto Sans SC', ui-sans-serif, system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

  /* Typography — Scale */
  --text-caption: 12px;
  --leading-caption: 1.5;
  --text-body-sm: 14px;
  --leading-body-sm: 1.5;
  --text-body: 16px;
  --leading-body: 1.5;
  --text-subheading: 18px;
  --leading-subheading: 1.4;
  --text-heading-sm: 21px;
  --leading-heading-sm: 1.35;
  --text-heading: 32px;
  --leading-heading: 1.2;
  --text-heading-lg: 49px;
  --leading-heading-lg: 1.15;
  --text-display: 65px;
  --leading-display: 1.1;
  --tracking-display: 0.01em;

  /* Spacing */
  --spacing-4: 4px;
  --spacing-8: 8px;
  --spacing-12: 12px;
  --spacing-16: 16px;
  --spacing-20: 20px;
  --spacing-24: 24px;
  --spacing-32: 32px;
  --spacing-40: 40px;
  --spacing-56: 56px;
  --spacing-72: 72px;
  --spacing-80: 80px;
  --spacing-112: 112px;
  --spacing-128: 128px;

  /* Layout */
  --page-max-width: 1200px;

  /* Border Radius */
  --radius-md: 4px;
  --radius-3xl: 32px;
  --radius-pill: 40px;
}

/* ============== Reset ============== */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; padding: 0; margin: 0; }
input, textarea, select { font: inherit; color: inherit; }

/* ============== Base ============== */
body {
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: var(--leading-body);
  color: var(--color-starlight);
  background-color: var(--color-deep-space);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-weight: 400;
  letter-spacing: 0.01em;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--color-starlight);
  margin: 0;
  letter-spacing: 0.01em;
}

p { margin: 0; color: var(--color-silver); }

::selection {
  background-color: var(--color-mercury-blue);
  color: var(--color-pure-white);
}

/* ============== Layout ============== */
.container {
  max-width: var(--page-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-24);
}

.section {
  padding: var(--spacing-112) 0;
}

.section-tight {
  padding: var(--spacing-80) 0;
}

@media (max-width: 768px) {
  .section { padding: var(--spacing-80) 0; }
  .section-tight { padding: var(--spacing-56) 0; }
  :root {
    --text-display: 42px;
    --text-heading-lg: 36px;
    --text-heading: 28px;
  }
}

/* ============== Header / Nav ============== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: 60px;
  padding: 0;
  display: flex;
  align-items: center;
  background-color: rgba(23, 23, 33, 0.6);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.site-header.scrolled {
  border-bottom-color: rgba(112, 112, 125, 0.2);
  background-color: rgba(23, 23, 33, 0.85);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-32);
}

.brand {
  font-family: var(--font-display);
  font-size: var(--text-body);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--color-starlight);
  display: flex;
  align-items: center;
  gap: var(--spacing-12);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  line-height: 1.1;
}

.brand-name {
  font-weight: 700;
  font-size: var(--text-body);
}

.brand-sub {
  font-family: 'Inter', 'Manrope', sans-serif;
  font-size: 10px;
  font-weight: 500;
  color: var(--color-silver);
  letter-spacing: 0.08em;
}

.brand-logo {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  object-fit: cover;
  flex-shrink: 0;
  display: block;
  box-shadow: 0 0 0 1px rgba(205, 221, 255, 0.12), 0 2px 8px rgba(0, 0, 0, 0.3);
}

.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-mercury-blue), #7a8aff);
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 14px;
  color: var(--color-pure-white);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-32);
}

.nav-link {
  font-size: var(--text-body-sm);
  font-weight: 400;
  color: var(--color-starlight);
  padding: var(--spacing-8) 0;
  transition: color 0.15s ease;
  position: relative;
}

.nav-link:hover { color: var(--color-ghost-blue); }
.nav-link.active { color: var(--color-pure-white); }

.nav-cta {
  display: inline-flex;
  align-items: center;
  padding: var(--spacing-8) var(--spacing-20);
  background-color: rgba(205, 221, 255, 0.12);
  color: var(--color-starlight);
  border-radius: var(--radius-pill);
  font-size: var(--text-body-sm);
  font-weight: 500;
  transition: background-color 0.15s ease, color 0.15s ease;
}

.nav-cta:hover {
  background-color: rgba(205, 221, 255, 0.22);
  color: var(--color-pure-white);
}

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(112, 112, 125, 0.3);
  align-items: center;
  justify-content: center;
}

.menu-toggle span {
  display: block;
  width: 16px;
  height: 1.5px;
  background-color: var(--color-starlight);
  position: relative;
}
.menu-toggle span::before,
.menu-toggle span::after {
  content: '';
  position: absolute;
  left: 0;
  width: 16px;
  height: 1.5px;
  background-color: var(--color-starlight);
}
.menu-toggle span::before { top: -5px; }
.menu-toggle span::after { top: 5px; }

@media (max-width: 860px) {
  .nav-links { display: none; }
  .nav-links.open {
    display: flex;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    padding: var(--spacing-24);
    gap: var(--spacing-20);
    background-color: var(--color-deep-space);
    border-bottom: 1px solid rgba(112, 112, 125, 0.2);
  }
  .menu-toggle { display: inline-flex; }
}

/* ============== Buttons ============== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-8);
  font-family: var(--font-body);
  font-size: var(--text-body);
  font-weight: 500;
  padding: var(--spacing-16) var(--spacing-24);
  border-radius: var(--radius-3xl);
  transition: transform 0.15s ease, background-color 0.15s ease, color 0.15s ease;
  white-space: nowrap;
  text-align: center;
  letter-spacing: 0.01em;
}

.btn-primary {
  background-color: var(--color-mercury-blue);
  color: var(--color-pure-white);
}
.btn-primary:hover {
  background-color: #6072f0;
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: rgba(205, 221, 255, 0.12);
  color: var(--color-starlight);
}
.btn-secondary:hover {
  background-color: rgba(205, 221, 255, 0.22);
  color: var(--color-pure-white);
}

.btn-ghost {
  background-color: transparent;
  color: var(--color-starlight);
  padding: var(--spacing-12) var(--spacing-20);
}
.btn-ghost:hover { color: var(--color-ghost-blue); }

.btn-sm { padding: var(--spacing-8) var(--spacing-20); font-size: var(--text-body-sm); }

.btn-arrow {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-8);
  color: var(--color-starlight);
  font-size: var(--text-body);
  font-weight: 500;
  padding: var(--spacing-8) 0;
  border-bottom: 1px solid transparent;
  transition: gap 0.2s ease, border-color 0.2s ease;
}
.btn-arrow:hover { gap: var(--spacing-12); border-color: var(--color-mercury-blue); }
.btn-arrow svg { transition: transform 0.2s ease; }
.btn-arrow:hover svg { transform: translateX(4px); }

/* ============== Hero ============== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding-top: 120px;
  padding-bottom: var(--spacing-80);
  overflow: hidden;
  background-color: var(--color-deep-space);
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  background-color: #0b0b16;
}

/* Layer 1: looping tech video (cinematic) */
.hero-bg video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.28;
  z-index: 1;
  filter: saturate(0.7) contrast(1.05) brightness(0.75) hue-rotate(-10deg);
}

/* Layer 1.5: animated neural network (primary tech visual) */
.hero-bg-network {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  pointer-events: none;
  opacity: 0.85;
}

/* Layer 2: animated mesh gradient (always-on ambient depth) */
.hero-bg-mesh {
  position: absolute;
  inset: -20%;
  z-index: 2;
  background:
    radial-gradient(circle at 18% 28%, rgba(82, 102, 235, 0.55), transparent 38%),
    radial-gradient(circle at 82% 18%, rgba(122, 138, 255, 0.45), transparent 40%),
    radial-gradient(circle at 50% 82%, rgba(82, 102, 235, 0.50), transparent 42%),
    radial-gradient(circle at 92% 68%, rgba(170, 130, 255, 0.35), transparent 38%),
    radial-gradient(circle at 12% 78%, rgba(82, 102, 235, 0.30), transparent 40%);
  animation: mesh-breathe 18s ease-in-out infinite;
  filter: blur(50px);
  mix-blend-mode: screen;
  pointer-events: none;
}

@keyframes mesh-breathe {
  0%, 100% { transform: scale(1) translate(0, 0) rotate(0deg); }
  33%      { transform: scale(1.12) translate(2%, -2%) rotate(1.5deg); }
  66%      { transform: scale(0.95) translate(-2%, 1%) rotate(-1.2deg); }
}

/* Layer 3: animated grid (tech blueprint feel) */
.hero-bg-grid {
  position: absolute;
  inset: 0;
  z-index: 3;
  background-image:
    linear-gradient(rgba(205, 221, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(205, 221, 255, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at center, black 0%, transparent 75%);
  mask-image: radial-gradient(ellipse 70% 60% at center, black 0%, transparent 75%);
  animation: grid-drift 40s linear infinite;
  pointer-events: none;
}

@keyframes grid-drift {
  0%   { background-position: 0 0, 0 0; }
  100% { background-position: 64px 64px, 64px 64px; }
}

/* Layer 4: floating particles */
.hero-bg-particles {
  position: absolute;
  inset: 0;
  z-index: 4;
  background-image:
    radial-gradient(2px 2px at 12% 22%, rgba(255, 255, 255, 0.95), transparent 50%),
    radial-gradient(1.5px 1.5px at 28% 68%, rgba(205, 221, 255, 0.7), transparent 50%),
    radial-gradient(1.5px 1.5px at 47% 38%, rgba(255, 255, 255, 0.6), transparent 50%),
    radial-gradient(2px 2px at 63% 75%, rgba(205, 221, 255, 0.85), transparent 50%),
    radial-gradient(1px 1px at 78% 28%, rgba(255, 255, 255, 0.7), transparent 50%),
    radial-gradient(1.5px 1.5px at 88% 62%, rgba(205, 221, 255, 0.6), transparent 50%),
    radial-gradient(1px 1px at 22% 88%, rgba(255, 255, 255, 0.5), transparent 50%),
    radial-gradient(2px 2px at 55% 12%, rgba(205, 221, 255, 0.8), transparent 50%),
    radial-gradient(1px 1px at 8% 55%, rgba(255, 255, 255, 0.55), transparent 50%),
    radial-gradient(1.5px 1.5px at 92% 88%, rgba(205, 221, 255, 0.65), transparent 50%);
  background-size: 100% 100%;
  background-repeat: no-repeat;
  animation: particles-drift 60s linear infinite;
  pointer-events: none;
}

@keyframes particles-drift {
  0%   { transform: translate(0, 0); opacity: 0.7; }
  50%  { opacity: 0.95; }
  100% { transform: translate(-30px, -40px); opacity: 0.7; }
}

/* Layer 5: scanline (subtle CRT / premium tech feel) */
.hero-bg-scan {
  position: absolute;
  inset: 0;
  z-index: 5;
  background: repeating-linear-gradient(
    180deg,
    transparent 0px,
    transparent 3px,
    rgba(255, 255, 255, 0.012) 3px,
    rgba(255, 255, 255, 0.012) 4px
  );
  pointer-events: none;
}

/* Layer 6: dark overlay for text readability */
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 6;
  background: linear-gradient(180deg,
    rgba(11, 11, 22, 0.30) 0%,
    rgba(11, 11, 22, 0.55) 45%,
    rgba(23, 23, 33, 0.85) 100%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 10;
  max-width: 900px;
  padding: 0 var(--spacing-24);
}


.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-8);
  padding: var(--spacing-8) var(--spacing-16);
  border: 1px solid rgba(112, 112, 125, 0.4);
  border-radius: var(--radius-pill);
  font-size: var(--text-caption);
  font-weight: 700;
  color: var(--color-ghost-blue);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: var(--spacing-32);
}

.eyebrow .dot {
  width: 6px;
  height: 6px;
  background-color: var(--color-mercury-blue);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--color-mercury-blue);
}

.hero h1 {
  font-size: var(--text-display);
  line-height: var(--leading-display);
  font-weight: 900;
  color: var(--color-starlight);
  margin-bottom: var(--spacing-24);
  letter-spacing: 0.005em;
}

.hero .subtitle {
  font-size: var(--text-heading-sm);
  font-weight: 400;
  color: var(--color-ghost-blue);
  margin-bottom: var(--spacing-24);
  letter-spacing: 0.02em;
}

.hero .description {
  font-size: var(--text-subheading);
  line-height: var(--leading-subheading);
  color: var(--color-silver);
  max-width: 640px;
  margin: 0 auto var(--spacing-40);
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  max-width: 480px;
  width: 100%;
  margin: 0 auto;
}

.hero-cta input {
  flex: 1;
  padding: var(--spacing-16) var(--spacing-24);
  background-color: rgba(30, 30, 42, 0.6);
  border: 1px solid rgba(112, 112, 125, 0.5);
  border-right: none;
  border-radius: 32px 0 0 32px;
  color: var(--color-starlight);
  font-size: var(--text-body);
  outline: none;
  transition: border-color 0.15s ease;
}

.hero-cta input::placeholder { color: var(--color-lead); }
.hero-cta input:focus { border-color: var(--color-ghost-blue); }

.hero-cta button {
  padding: var(--spacing-16) var(--spacing-32);
  background-color: var(--color-mercury-blue);
  color: var(--color-pure-white);
  border-radius: 0 32px 32px 0;
  font-size: var(--text-body);
  font-weight: 500;
  transition: background-color 0.15s ease;
  white-space: nowrap;
}

.hero-cta button:hover { background-color: #6072f0; }

.hero-meta {
  margin-top: var(--spacing-24);
  font-size: var(--text-caption);
  color: var(--color-silver);
  letter-spacing: 0.02em;
}

@media (max-width: 640px) {
  .hero-cta {
    flex-direction: column;
    gap: var(--spacing-12);
  }
  .hero-cta input {
    border-radius: 32px;
    border-right: 1px solid rgba(112, 112, 125, 0.5);
    width: 100%;
  }
  .hero-cta button {
    border-radius: 32px;
    width: 100%;
  }
}

/* ============== Trust Bar / Stats ============== */
.trust-bar {
  background-color: var(--color-deep-space);
  border-top: 1px solid rgba(112, 112, 125, 0.15);
  border-bottom: 1px solid rgba(112, 112, 125, 0.15);
  padding: var(--spacing-56) 0;
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-32);
  text-align: center;
}

.stat-num {
  font-family: var(--font-display);
  font-size: var(--text-heading-lg);
  font-weight: 800;
  color: var(--color-starlight);
  line-height: 1;
  letter-spacing: -0.01em;
  margin-bottom: var(--spacing-8);
}

.stat-num .unit {
  font-size: 0.5em;
  color: var(--color-ghost-blue);
  margin-left: 4px;
  font-weight: 400;
}

.stat-label {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  letter-spacing: 0.02em;
}

@media (max-width: 768px) {
  .stats { grid-template-columns: repeat(2, 1fr); gap: var(--spacing-32) var(--spacing-16); }
}

/* ============== Section Headers ============== */
.section-head {
  max-width: 720px;
  margin: 0 auto var(--spacing-72);
  text-align: center;
}

.section-head.left {
  margin-left: 0;
  text-align: left;
}

.section-eyebrow {
  font-size: var(--text-caption);
  font-weight: 700;
  color: var(--color-mercury-blue);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  margin-bottom: var(--spacing-16);
}

.section-head h2 {
  font-size: var(--text-heading-lg);
  line-height: var(--leading-heading-lg);
  font-weight: 800;
  margin-bottom: var(--spacing-20);
  letter-spacing: 0.005em;
}

.section-head p {
  font-size: var(--text-subheading);
  line-height: var(--leading-subheading);
  color: var(--color-silver);
}

/* ============== Service Cards ============== */
.services {
  background-color: var(--color-midnight-slate);
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
  border-top: 1px solid var(--color-lead);
  border-left: 1px solid var(--color-lead);
}

.service-card {
  padding: var(--spacing-40);
  border-right: 1px solid var(--color-lead);
  border-bottom: 1px solid var(--color-lead);
  background-color: var(--color-midnight-slate);
  transition: background-color 0.2s ease;
  position: relative;
  min-height: 280px;
  display: flex;
  flex-direction: column;
}

.service-card:hover {
  background-color: var(--color-graphite);
}

.service-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background-color: var(--color-graphite);
  display: grid;
  place-items: center;
  margin-bottom: var(--spacing-24);
  color: var(--color-mercury-blue);
}

.service-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-heading-sm);
  font-weight: 700;
  color: var(--color-starlight);
  margin-bottom: var(--spacing-12);
  line-height: var(--leading-heading-sm);
  letter-spacing: 0.005em;
}

.service-card p {
  color: var(--color-silver);
  font-size: var(--text-body);
  line-height: 1.6;
  flex: 1;
  margin-bottom: var(--spacing-24);
}

.service-card .more {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-8);
  color: var(--color-ghost-blue);
  font-size: var(--text-body-sm);
  font-weight: 500;
}

.service-card .more svg { transition: transform 0.2s ease; }
.service-card:hover .more svg { transform: translateX(4px); }


@media (max-width: 768px) {
  .service-grid { grid-template-columns: 1fr; }
}

/* ============== Process ============== */
.process {
  background-color: var(--color-deep-space);
}

.process-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-24);
  position: relative;
}

.process-step {
  position: relative;
  padding: var(--spacing-32) var(--spacing-24);
  border: 1px solid rgba(112, 112, 125, 0.3);
  background-color: var(--color-midnight-slate);
}

.process-num {
  font-family: var(--font-display);
  font-size: var(--text-heading);
  font-weight: 700;
  color: var(--color-mercury-blue);
  line-height: 1;
  margin-bottom: var(--spacing-24);
  display: flex;
  align-items: baseline;
  gap: var(--spacing-8);
}

.process-num .step-label {
  font-family: var(--font-body);
  font-size: var(--text-caption);
  font-weight: 500;
  color: var(--color-silver);
  text-transform: uppercase;
  letter-spacing: 0.16em;
}

.process-step h3 {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  margin-bottom: var(--spacing-12);
  line-height: var(--leading-heading-sm);
  letter-spacing: 0.005em;
}

.process-step p {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  line-height: 1.6;
}

@media (max-width: 900px) {
  .process-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 540px) {
  .process-grid { grid-template-columns: 1fr; }
}

/* ============== Why Us ============== */
.why {
  background-color: var(--color-midnight-slate);
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-56) var(--spacing-48);
}

.why-item {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-32);
  padding: var(--spacing-24) 0;
  border-top: 1px solid var(--color-lead);
}

.why-body {
  flex: 1 1 auto;
  min-width: 0;
}

.why-num {
  font-family: var(--font-display);
  font-size: var(--text-body);
  font-weight: 500;
  color: var(--color-mercury-blue);
  margin-bottom: var(--spacing-12);
  letter-spacing: 0.08em;
}

.why-item h3 {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  margin-bottom: var(--spacing-12);
  letter-spacing: 0.005em;
}

.why-item p {
  color: var(--color-silver);
  font-size: var(--text-body);
  line-height: 1.6;
}

.why-avatar {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  flex: 0 0 220px;
  display: block;
  object-fit: cover;
  box-shadow: 0 8px 24px rgba(82, 102, 235, 0.25);
}

@media (max-width: 900px) {
  .why-grid { grid-template-columns: 1fr; gap: var(--spacing-40); }
  .why-item { flex-direction: column; align-items: center; text-align: center; }
  .why-avatar { width: 140px; height: 140px; flex-basis: 140px; }
}

/* ============== Feature Link List ============== */
.feature-list {
  display: flex;
  flex-direction: column;
}

.feature-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-32) 0;
  border-bottom: 1px solid var(--color-lead);
  transition: padding 0.2s ease;
}

.feature-link:first-child { border-top: 1px solid var(--color-lead); }

.feature-link:hover { padding-left: var(--spacing-12); padding-right: var(--spacing-12); }

.feature-link-text h3 {
  font-family: var(--font-display);
  font-size: var(--text-heading-sm);
  font-weight: 700;
  color: var(--color-starlight);
  margin-bottom: var(--spacing-8);
  letter-spacing: 0.005em;
}

.feature-link-text p {
  color: var(--color-silver);
  font-size: var(--text-body);
  line-height: 1.5;
}

.feature-link-arrow {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid var(--color-lead);
  display: grid;
  place-items: center;
  color: var(--color-starlight);
  flex-shrink: 0;
  margin-left: var(--spacing-24);
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.feature-link:hover .feature-link-arrow {
  background-color: var(--color-mercury-blue);
  border-color: var(--color-mercury-blue);
  color: var(--color-pure-white);
}

/* ============== Final CTA ============== */
.cta-final {
  background-color: var(--color-deep-space);
  position: relative;
  overflow: hidden;
}

.cta-final::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at center top, rgba(82, 102, 235, 0.15) 0%, transparent 60%);
  pointer-events: none;
}

.cta-final-inner {
  position: relative;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-80) var(--spacing-24);
}

.cta-final h2 {
  font-size: var(--text-heading-lg);
  line-height: var(--leading-heading-lg);
  font-weight: 800;
  margin-bottom: var(--spacing-24);
  letter-spacing: 0.005em;
}

.cta-final p {
  font-size: var(--text-subheading);
  color: var(--color-silver);
  margin-bottom: var(--spacing-40);
  line-height: var(--leading-subheading);
}

.cta-final .btn-row {
  display: inline-flex;
  flex-wrap: wrap;
  gap: var(--spacing-12);
  justify-content: center;
}

/* ============== Footer ============== */
.site-footer {
  background-color: var(--color-deep-space);
  border-top: 1px solid rgba(112, 112, 125, 0.2);
  padding: var(--spacing-80) 0 var(--spacing-40);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--spacing-56) var(--spacing-40);
  margin-bottom: var(--spacing-72);
}

.footer-brand {
  max-width: 320px;
}

.footer-brand p {
  margin-top: var(--spacing-16);
  font-size: var(--text-body-sm);
  line-height: 1.6;
  color: var(--color-silver);
}

.footer-col h4 {
  font-family: var(--font-body);
  font-size: var(--text-caption);
  font-weight: 500;
  color: var(--color-starlight);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  margin-bottom: var(--spacing-20);
}

.footer-col ul { display: flex; flex-direction: column; gap: var(--spacing-12); }

.footer-link {
  color: var(--color-silver);
  font-size: var(--text-body-sm);
  transition: color 0.15s ease;
}
.footer-link:hover { color: var(--color-ghost-blue); }

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--spacing-32);
  border-top: 1px solid rgba(112, 112, 125, 0.2);
  font-size: var(--text-caption);
  color: var(--color-silver);
  letter-spacing: 0.02em;
  flex-wrap: wrap;
  gap: var(--spacing-16);
}

.footer-bottom .legal { display: flex; gap: var(--spacing-24); }

@media (max-width: 768px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

/* ============== Page Hero (subpages) ============== */
.page-hero {
  padding: 180px 0 var(--spacing-80);
  background-color: var(--color-deep-space);
  position: relative;
  text-align: center;
  border-bottom: 1px solid rgba(112, 112, 125, 0.15);
}

.page-hero h1 {
  font-size: var(--text-display);
  line-height: var(--leading-display);
  font-weight: 800;
  margin-bottom: var(--spacing-24);
  letter-spacing: 0.005em;
}

.page-hero .lead {
  font-size: var(--text-subheading);
  color: var(--color-silver);
  max-width: 640px;
  margin: 0 auto;
  line-height: var(--leading-subheading);
}

/* ============== Detail Service Sections ============== */
.detail-block {
  background-color: var(--color-deep-space);
  border-top: 1px solid rgba(112, 112, 125, 0.15);
}

.detail-block.alt { background-color: var(--color-midnight-slate); }

.detail-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--spacing-72);
  align-items: center;
}

.detail-block.reverse .detail-grid {
  grid-template-columns: 1.2fr 1fr;
}

.detail-block.reverse .detail-text { order: 2; }
.detail-block.reverse .detail-visual { order: 1; }

.detail-text h2 {
  font-size: var(--text-heading);
  line-height: var(--leading-heading);
  font-weight: 700;
  margin-bottom: var(--spacing-20);
  letter-spacing: 0.005em;
}

.detail-text .label {
  font-size: var(--text-caption);
  color: var(--color-mercury-blue);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  margin-bottom: var(--spacing-16);
  display: block;
}

.detail-text p {
  font-size: var(--text-body);
  color: var(--color-silver);
  line-height: 1.7;
  margin-bottom: var(--spacing-20);
}

.detail-text ul {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-12);
  margin-top: var(--spacing-24);
}

.detail-text li {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-12);
  color: var(--color-starlight);
  font-size: var(--text-body);
  line-height: 1.6;
}

.detail-text li::before {
  content: '';
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-mercury-blue);
  margin-top: 10px;
  flex-shrink: 0;
}

.detail-visual {
  position: relative;
  aspect-ratio: 4 / 3;
  background-color: var(--color-graphite);
  overflow: hidden;
  border: 1px solid var(--color-lead);
}

.detail-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.9) saturate(0.95);
  transition: transform 0.4s ease;
}

.detail-visual:hover img { transform: scale(1.04); }

@media (max-width: 860px) {
  .detail-grid,
  .detail-block.reverse .detail-grid { grid-template-columns: 1fr; }
  .detail-block.reverse .detail-text { order: 1; }
  .detail-block.reverse .detail-visual { order: 2; }
}

/* ============== About: Mission & Team ============== */
.mission {
  background-color: var(--color-midnight-slate);
}

.mission-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-40);
}

.mission-card {
  padding: var(--spacing-40);
  border: 1px solid var(--color-lead);
  background-color: var(--color-deep-space);
}

.mission-card h3 {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  margin-bottom: var(--spacing-16);
  letter-spacing: 0.005em;
}

.mission-card p {
  font-size: var(--text-body);
  color: var(--color-silver);
  line-height: 1.7;
}

@media (max-width: 768px) {
  .mission-grid { grid-template-columns: 1fr; }
}

.certs {
  background-color: var(--color-deep-space);
}

.certs-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-32);
}

.cert-card {
  background: linear-gradient(180deg, rgba(82, 102, 235, 0.06) 0%, rgba(30, 30, 42, 0) 100%);
  border: 1px solid var(--color-lead);
  border-radius: 12px;
  padding: var(--spacing-32);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.cert-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-mercury-blue);
  box-shadow: 0 16px 48px rgba(82, 102, 235, 0.18);
}

.cert-badge {
  width: 72px;
  height: 86px;
  margin-bottom: var(--spacing-20);
}

.cert-name {
  font-family: var(--font-body);
  font-size: var(--text-body);
  font-weight: 600;
  color: var(--color-starlight);
  margin-bottom: var(--spacing-12);
  letter-spacing: 0.02em;
}

.cert-org {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  margin-bottom: var(--spacing-16);
  line-height: 1.5;
}

.cert-meta {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
  font-size: var(--text-body-sm);
  color: var(--color-mercury-blue);
  font-family: var(--font-display);
  letter-spacing: 0.04em;
}

.cert-no {
  opacity: 0.7;
  font-size: 12px;
}

@media (max-width: 900px) {
  .certs-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 540px) {
  .certs-grid { grid-template-columns: 1fr; }
}

/* ============== Forms ============== */
.form-block {
  background-color: var(--color-deep-space);
}

.form-wrap {
  max-width: 640px;
  margin: 0 auto;
  padding: var(--spacing-56);
  background-color: var(--color-midnight-slate);
  border: 1px solid var(--color-lead);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-20);
}

@media (max-width: 640px) {
  .form-row { grid-template-columns: 1fr; }
  .form-wrap { padding: var(--spacing-32); }
}

.field {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-8);
  margin-bottom: var(--spacing-20);
}

.field label {
  font-size: var(--text-body-sm);
  font-weight: 500;
  color: var(--color-starlight);
}

.field label .req { color: var(--color-mercury-blue); }

.field input,
.field textarea,
.field select {
  padding: var(--spacing-12) var(--spacing-16);
  background-color: var(--color-deep-space);
  border: 1px solid var(--color-lead);
  border-radius: var(--radius-md);
  color: var(--color-starlight);
  font-size: var(--text-body);
  outline: none;
  transition: border-color 0.15s ease;
  width: 100%;
  font-family: inherit;
}

.field input::placeholder,
.field textarea::placeholder { color: var(--color-lead); }

.field input:focus,
.field textarea:focus,
.field select:focus { border-color: var(--color-mercury-blue); }

.field textarea { min-height: 140px; resize: vertical; }

.field .hint {
  font-size: var(--text-caption);
  color: var(--color-silver);
}

.form-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: var(--spacing-32);
  flex-wrap: wrap;
  gap: var(--spacing-16);
}

.form-note { font-size: var(--text-caption); color: var(--color-silver); }

.form-success {
  display: none;
  padding: var(--spacing-16);
  background-color: rgba(82, 102, 235, 0.12);
  border: 1px solid var(--color-mercury-blue);
  border-radius: var(--radius-md);
  color: var(--color-ghost-blue);
  font-size: var(--text-body-sm);
  margin-top: var(--spacing-20);
}

.form-success.show { display: block; }

/* ============== Contact Info ============== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--color-lead);
  margin-bottom: var(--spacing-72);
}

.contact-card {
  padding: var(--spacing-40);
  border-right: 1px solid var(--color-lead);
  background-color: var(--color-midnight-slate);
}
.contact-card:last-child { border-right: none; }

.contact-card .icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background-color: var(--color-graphite);
  display: grid;
  place-items: center;
  color: var(--color-mercury-blue);
  margin-bottom: var(--spacing-20);
}

.contact-card h3 {
  font-family: var(--font-body);
  font-size: var(--text-body-sm);
  font-weight: 500;
  color: var(--color-silver);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: var(--spacing-12);
}

.contact-card .value {
  font-family: var(--font-display);
  font-size: var(--text-heading-sm);
  font-weight: 700;
  color: var(--color-starlight);
  line-height: 1.4;
  margin-bottom: var(--spacing-8);
}

.contact-card .sub {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  line-height: 1.5;
}

@media (max-width: 768px) {
  .contact-grid { grid-template-columns: 1fr; }
  .contact-card { border-right: none; border-bottom: 1px solid var(--color-lead); }
  .contact-card:last-child { border-bottom: none; }
}

/* ============== Process Flow (apply page) ============== */
.flow {
  background-color: var(--color-midnight-slate);
}

.flow-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border: 1px solid var(--color-lead);
  position: relative;
}

.flow-step {
  padding: var(--spacing-40) var(--spacing-24);
  border-right: 1px solid var(--color-lead);
  background-color: var(--color-deep-space);
  position: relative;
}
.flow-step:last-child { border-right: none; }

.flow-step .step-no {
  font-family: var(--font-display);
  font-size: var(--text-body-sm);
  font-weight: 500;
  color: var(--color-mercury-blue);
  margin-bottom: var(--spacing-20);
  letter-spacing: 0.12em;
}

.flow-step h3 {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  margin-bottom: var(--spacing-12);
  letter-spacing: 0.005em;
}

.flow-step p {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  line-height: 1.6;
  margin-bottom: var(--spacing-20);
}

.flow-step .time {
  font-size: var(--text-caption);
  color: var(--color-ghost-blue);
  font-weight: 500;
  letter-spacing: 0.04em;
}

@media (max-width: 900px) {
  .flow-grid { grid-template-columns: repeat(2, 1fr); }
  .flow-step { border-right: none; border-bottom: 1px solid var(--color-lead); }
}
@media (max-width: 540px) {
  .flow-grid { grid-template-columns: 1fr; }
}

/* ============== Apply split layout ============== */
.apply-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-72);
  align-items: start;
}

.apply-side h2 {
  font-size: var(--text-heading);
  font-weight: 700;
  margin-bottom: var(--spacing-20);
  line-height: var(--leading-heading);
  letter-spacing: 0.005em;
}

.apply-side p {
  font-size: var(--text-body);
  color: var(--color-silver);
  line-height: 1.7;
  margin-bottom: var(--spacing-24);
}

.apply-side .check-list { margin-top: var(--spacing-32); display: flex; flex-direction: column; gap: var(--spacing-16); }
.apply-side .check-list li {
  display: flex;
  gap: var(--spacing-12);
  color: var(--color-starlight);
  font-size: var(--text-body);
  align-items: flex-start;
}
.apply-side .check-list li svg { color: var(--color-mercury-blue); flex-shrink: 0; margin-top: 4px; }

@media (max-width: 860px) {
  .apply-split { grid-template-columns: 1fr; gap: var(--spacing-40); }
}

/* ============== Animations ============== */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  * { transition-duration: 0s !important; animation-duration: 0s !important; }
}

/* =========================================================
   OPC 内容扩展（首页新结构）
   ========================================================= */

/* 3 列服务网格（6 项服务 2x3） */
.service-grid-3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 900px) { .service-grid-3 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .service-grid-3 { grid-template-columns: 1fr; } }

/* ----- 什么是 OPC 区块 ----- */
.opc-intro-section { background-color: var(--color-deep-space); }

.opc-intro {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: var(--spacing-72);
  align-items: center;
}

.opc-intro-text .lead {
  font-family: var(--font-display);
  font-size: var(--text-heading-sm);
  line-height: var(--leading-heading-sm);
  color: var(--color-starlight);
  font-weight: 500;
  margin-bottom: var(--spacing-20);
}

.opc-intro-text .lead strong { color: var(--color-ghost-blue); font-weight: 700; }

.opc-intro-text p { color: var(--color-silver); line-height: 1.8; margin-bottom: var(--spacing-24); }

.opc-bullets { display: flex; flex-direction: column; gap: var(--spacing-20); margin-top: var(--spacing-32); }
.opc-bullets li {
  display: flex;
  gap: var(--spacing-20);
  align-items: flex-start;
  color: var(--color-silver);
  line-height: 1.7;
  font-size: var(--text-body);
}
.opc-bullets strong { color: var(--color-starlight); font-weight: 600; }

.bullet-num {
  font-family: var(--font-display);
  font-size: var(--text-body);
  font-weight: 700;
  color: var(--color-mercury-blue);
  letter-spacing: 0.06em;
  flex-shrink: 0;
  margin-top: 2px;
  min-width: 28px;
}

/* OPC 公式视觉 */
.opc-formula {
  padding: var(--spacing-40);
  background: linear-gradient(180deg, var(--color-midnight-slate), var(--color-deep-space));
  border: 1px solid var(--color-lead);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-12);
}
.formula-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-20) var(--spacing-24);
  background-color: var(--color-graphite);
  border: 1px solid rgba(112, 112, 125, 0.3);
}
.formula-row.formula-result {
  background: linear-gradient(135deg, rgba(82, 102, 235, 0.2), rgba(82, 102, 235, 0.08));
  border-color: var(--color-mercury-blue);
}
.formula-text {
  font-family: var(--font-display);
  font-size: var(--text-heading-sm);
  font-weight: 700;
  color: var(--color-starlight);
  letter-spacing: 0.02em;
}
.formula-result .formula-text { color: var(--color-pure-white); }
.formula-op {
  font-family: var(--font-display);
  font-size: var(--text-heading);
  font-weight: 300;
  color: var(--color-mercury-blue);
  line-height: 1;
}

@media (max-width: 860px) {
  .opc-intro { grid-template-columns: 1fr; gap: var(--spacing-40); }
}

/* ----- 谁适合 OPC ----- */
.audience-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
  border-top: 1px solid var(--color-lead);
  border-left: 1px solid var(--color-lead);
}
.audience-card {
  padding: var(--spacing-40);
  border-right: 1px solid var(--color-lead);
  border-bottom: 1px solid var(--color-lead);
  background-color: var(--color-deep-space);
  transition: background-color 0.2s ease;
}
.audience-card:hover { background-color: var(--color-graphite); }

.audience-num {
  font-family: var(--font-display);
  font-size: 48px;
  font-weight: 200;
  color: var(--color-mercury-blue);
  line-height: 1;
  margin-bottom: var(--spacing-24);
  letter-spacing: -0.02em;
}
.audience-card h3 {
  font-size: var(--text-heading-sm);
  font-weight: 700;
  margin-bottom: var(--spacing-12);
  letter-spacing: 0.005em;
}
.audience-card p {
  color: var(--color-silver);
  font-size: var(--text-body);
  line-height: 1.7;
}
@media (max-width: 768px) { .audience-grid { grid-template-columns: 1fr; } }

/* ----- 5 步流程 ----- */
.process-grid-5 { grid-template-columns: repeat(5, 1fr); }
@media (max-width: 1100px) { .process-grid-5 { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 700px)  { .process-grid-5 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px)  { .process-grid-5 { grid-template-columns: 1fr; } }

.step-time {
  margin-top: var(--spacing-16);
  padding-top: var(--spacing-12);
  border-top: 1px solid rgba(112, 112, 125, 0.2);
  font-size: var(--text-caption);
  font-weight: 500;
  color: var(--color-ghost-blue);
  letter-spacing: 0.06em;
}

/* ----- 学员案例 ----- */
.testimonial-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-24);
}
.testimonial-card {
  position: relative;
  padding: var(--spacing-40);
  background-color: var(--color-deep-space);
  border: 1px solid var(--color-lead);
  display: flex;
  flex-direction: column;
  min-height: 320px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.testimonial-card:hover {
  border-color: var(--color-mercury-blue);
  transform: translateY(-2px);
}
.testimonial-quote {
  font-family: var(--font-display);
  font-size: 72px;
  font-weight: 300;
  color: var(--color-mercury-blue);
  line-height: 0.6;
  margin-bottom: var(--spacing-8);
  opacity: 0.6;
}
.testimonial-text {
  color: var(--color-silver);
  font-size: var(--text-body);
  line-height: 1.75;
  flex: 1;
  margin-bottom: var(--spacing-32);
}
.testimonial-text strong { color: var(--color-starlight); font-weight: 600; }

.testimonial-author {
  display: flex;
  align-items: center;
  gap: var(--spacing-12);
  padding-top: var(--spacing-20);
  border-top: 1px solid rgba(112, 112, 125, 0.2);
}
.testimonial-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-mercury-blue), #7a8aff);
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--color-pure-white);
  font-size: var(--text-body);
  flex-shrink: 0;
}
.testimonial-name {
  font-family: var(--font-display);
  font-size: var(--text-body);
  font-weight: 700;
  color: var(--color-starlight);
  margin-bottom: 2px;
}
.testimonial-role {
  font-size: var(--text-caption);
  color: var(--color-silver);
  letter-spacing: 0.02em;
}

@media (max-width: 900px) { .testimonial-grid { grid-template-columns: 1fr; } }

/* ----- 强化 hero 描述中的 strong 标签 ----- */
.hero .description strong { color: var(--color-ghost-blue); font-weight: 600; }

/* Honeypot 隐藏字段（Netlify Forms 反垃圾） */
.hidden-field {
  position: absolute !important;
  left: -9999px !important;
  width: 1px !important;
  height: 1px !important;
  overflow: hidden !important;
  opacity: 0 !important;
  pointer-events: none !important;
}

/* ============== Team Credentials (Image Gallery) ============== */
.cert-gallery {
  background-color: var(--color-midnight-slate);
  position: relative;
}

.cert-gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--spacing-32);
  max-width: 1080px;
  margin: 0 auto;
}

.cert-image-card {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  text-align: left;
  background: linear-gradient(180deg, rgba(82, 102, 235, 0.08) 0%, rgba(30, 30, 42, 0) 100%);
  border: 1px solid var(--color-lead);
  border-radius: 16px;
  padding: var(--spacing-20);
  cursor: pointer;
  transition: transform 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
  font: inherit;
  color: inherit;
  appearance: none;
  width: 100%;
}

.cert-image-card:hover,
.cert-image-card:focus-visible {
  transform: translateY(-4px);
  border-color: var(--color-mercury-blue);
  box-shadow: 0 20px 60px rgba(82, 102, 235, 0.22);
  outline: none;
}

.cert-image-frame {
  position: relative;
  overflow: hidden;
  border-radius: 10px;
  background: #0d0d15;
  aspect-ratio: 16 / 11;
  display: flex;
  align-items: center;
  justify-content: center;
}

.cert-image-frame img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  transition: transform 0.5s ease;
}

.cert-image-card:hover .cert-image-frame img {
  transform: scale(1.02);
}

.cert-zoom {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(13, 13, 21, 0.72);
  color: var(--color-starlight);
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
}

.cert-image-card:hover .cert-zoom,
.cert-image-card:focus-visible .cert-zoom {
  opacity: 1;
  transform: translateY(0);
}

.cert-image-meta {
  padding: var(--spacing-20) var(--spacing-8) var(--spacing-8);
}

.cert-image-name {
  font-family: var(--font-body);
  font-size: var(--text-subheading);
  font-weight: 600;
  color: var(--color-starlight);
  margin-bottom: 6px;
  letter-spacing: 0.01em;
}

.cert-image-org {
  font-size: var(--text-body-sm);
  color: var(--color-silver);
  margin-bottom: var(--spacing-12);
  line-height: 1.5;
}

.cert-image-row {
  display: flex;
  gap: var(--spacing-16);
  font-family: var(--font-display);
  font-size: 12px;
  color: var(--color-mercury-blue);
  letter-spacing: 0.06em;
  opacity: 0.85;
}

/* ===== Lightbox ===== */
.cert-lightbox {
  position: fixed;
  inset: 0;
  background: rgba(8, 8, 14, 0.92);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.cert-lightbox.open {
  opacity: 1;
  visibility: visible;
}

.cert-lightbox-inner {
  max-width: min(1200px, 96vw);
  max-height: 92vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  transform: scale(0.96);
  transition: transform 0.3s ease;
}

.cert-lightbox.open .cert-lightbox-inner {
  transform: scale(1);
}

.cert-lightbox-img {
  max-width: 100%;
  max-height: 84vh;
  width: auto;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.6);
  background: #fff;
}

.cert-lightbox-caption {
  color: var(--color-silver);
  font-size: var(--text-body-sm);
  letter-spacing: 0.04em;
  text-align: center;
}

.cert-lightbox-close {
  position: absolute;
  top: 24px;
  right: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: var(--color-starlight);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, 0.12);
  transition: background 0.2s ease, transform 0.2s ease;
  z-index: 1;
}

.cert-lightbox-close:hover {
  background: rgba(255, 255, 255, 0.16);
  transform: rotate(90deg);
}

body.cert-lb-open {
  overflow: hidden;
}

@media (max-width: 720px) {
  .cert-gallery-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-24);
  }
  .cert-lightbox { padding: 16px; }
  .cert-lightbox-close { top: 12px; right: 12px; }
}

/* ============== Skip link (a11y) ============== */
.skip-link {
  position: absolute;
  top: -64px;
  left: 16px;
  z-index: 9999;
  padding: 10px 16px;
  background: var(--color-primary, #5266eb);
  color: #fff;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  border-radius: 6px;
  transition: top 0.18s ease;
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 16px;
  outline: 2px solid #fff;
  outline-offset: 2px;
}

/* ============== Active nav link ============== */
.nav a.active {
  color: var(--color-primary, #5266eb);
  position: relative;
}
.nav a.active::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -8px;
  height: 2px;
  background: var(--color-primary, #5266eb);
  border-radius: 2px;
}

/* ============== Back to top ============== */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 900;
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(20, 23, 35, 0.85);
  color: #ededf3;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}
.back-to-top.show {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}
.back-to-top:hover {
  background: var(--color-primary, #5266eb);
  border-color: var(--color-primary, #5266eb);
}
.back-to-top:focus-visible {
  outline: 2px solid var(--color-primary, #5266eb);
  outline-offset: 2px;
}
@media (max-width: 720px) {
  .back-to-top { right: 16px; bottom: 16px; width: 40px; height: 40px; }
}

/* ============== Smooth scroll for in-page anchors ============== */
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

/* ============== Legal Pages (privacy.html / terms.html) ============== */
.legal-content {
  max-width: 880px;
  margin: 0 auto;
  font-size: var(--text-body, 16px);
  line-height: 1.85;
  color: var(--color-silver, #cbd1d8);
}

.legal-content h3 {
  font-size: var(--text-heading-sm, 20px);
  font-weight: 700;
  color: var(--color-white, #ffffff);
  margin-top: var(--spacing-56, 56px);
  margin-bottom: var(--spacing-16, 16px);
  padding-left: 14px;
  border-left: 3px solid var(--color-primary, #5266eb);
  line-height: 1.4;
}

.legal-content p {
  margin-bottom: var(--spacing-16, 16px);
}

.legal-content ul {
  margin: 0 0 var(--spacing-24, 24px) 0;
  padding-left: var(--spacing-24, 24px);
  list-style: disc;
}

.legal-content ul li {
  margin-bottom: var(--spacing-12, 12px);
  padding-left: var(--spacing-8, 8px);
}

.legal-content ul li::marker {
  color: var(--color-mercury-blue, #67b8ff);
}

.legal-content strong {
  color: var(--color-white, #ffffff);
  font-weight: 600;
}

.legal-content a {
  color: var(--color-mercury-blue, #67b8ff);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}

.legal-content a:hover {
  border-bottom-color: var(--color-mercury-blue, #67b8ff);
}

.legal-content .legal-note {
  margin-top: var(--spacing-56, 56px);
  padding: var(--spacing-20, 20px) var(--spacing-24, 24px);
  background: rgba(82, 102, 235, 0.06);
  border-left: 3px solid var(--color-primary, #5266eb);
  border-radius: 4px;
  font-size: var(--text-body-sm, 14px);
  color: var(--color-silver, #cbd1d8);
}

/* ============== Footer disabled links (敬请期待) ============== */
.footer-link--disabled {
  cursor: default;
  pointer-events: none;
  color: var(--color-silver, #cbd1d8);
  opacity: 0.55;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.footer-link--disabled small {
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.06em;
  padding: 2px 6px;
  border-radius: 999px;
  background: rgba(82, 102, 235, 0.18);
  color: var(--color-mercury-blue, #67b8ff);
  text-transform: uppercase;
}

/* ============== Legal page H1 (privacy / terms) ============== */
.page-h1 {
  font-size: 36px;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 8px;
  color: var(--color-white, #ffffff);
  letter-spacing: -0.01em;
}

@media (max-width: 768px) {
  .page-h1 { font-size: 28px; }
}

/* ============== Form error (inline) ============== */
.form-error {
  display: none;
  padding: var(--spacing-12) var(--spacing-16);
  background-color: rgba(232, 89, 89, 0.10);
  border: 1px solid rgba(232, 89, 89, 0.45);
  border-radius: var(--radius-md);
  color: #ff8a8a;
  font-size: var(--text-body-sm);
  margin-top: var(--spacing-16);
  animation: formErrorShake 0.35s ease-out;
}

.form-error.show { display: block; }

.form-error::before {
  content: "⚠ ";
  margin-right: 4px;
}

@keyframes formErrorShake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-4px); }
  75% { transform: translateX(4px); }
}

/* ============== Cookie consent banner ============== */
.cookie-banner {
  position: fixed;
  left: 16px;
  right: 16px;
  bottom: 16px;
  max-width: 720px;
  margin: 0 auto;
  padding: 18px 22px;
  background: rgba(15, 18, 28, 0.96);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(103, 184, 255, 0.25);
  border-radius: 14px;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
  color: var(--color-silver, #cbd1d8);
  font-size: 14px;
  line-height: 1.6;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 12px;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.cookie-banner.show {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.cookie-banner-title {
  font-weight: 700;
  font-size: 15px;
  color: var(--color-white, #ffffff);
  display: flex;
  align-items: center;
  gap: 8px;
}

.cookie-banner-title::before {
  content: "🍪";
}

.cookie-banner-text {
  color: var(--color-silver, #cbd1d8);
}

.cookie-banner-text a {
  color: var(--color-mercury-blue, #67b8ff);
  text-decoration: none;
  border-bottom: 1px solid rgba(103, 184, 255, 0.4);
}

.cookie-banner-text a:hover {
  border-bottom-color: var(--color-mercury-blue);
}

.cookie-banner-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.cookie-banner-btn {
  flex: 1;
  min-width: 130px;
  padding: 10px 16px;
  border-radius: 8px;
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: inherit;
}

.cookie-banner-btn-accept {
  background: var(--color-primary, #5266eb);
  color: #ffffff;
}

.cookie-banner-btn-accept:hover {
  background: #3f52d8;
  transform: translateY(-1px);
}

.cookie-banner-btn-necessary {
  background: transparent;
  color: var(--color-silver, #cbd1d8);
  border-color: rgba(203, 209, 216, 0.3);
}

.cookie-banner-btn-necessary:hover {
  border-color: var(--color-mercury-blue, #67b8ff);
  color: var(--color-white, #ffffff);
}

@media (max-width: 600px) {
  .cookie-banner {
    left: 8px;
    right: 8px;
    bottom: 8px;
    padding: 14px 16px;
  }
  .cookie-banner-actions { flex-direction: column; }
  .cookie-banner-btn { width: 100%; }
}