/* ===== Google Fonts ===== */
@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=DM+Sans:ital,wght@0,400;0,500;0,600;1,400&display=swap');

/* ===== CSS Variables ===== */
:root {
  --color-primary: #0071e3;
  --color-primary-dark: #0058b0;
  --color-primary-light: #e8f4fd;
  --color-text: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-text-tertiary: #86868b;
  --color-bg: #ffffff;
  --color-bg-secondary: #f5f5f7;
  --color-border: #d2d2d7;
  --color-border-light: #e8e8ed;
  --font-display: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: 'DM Sans', -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 22px;
  --radius-pill: 100px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.05), 0 1px 3px rgba(0,0,0,0.05);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
  --shadow-xl: 0 24px 60px rgba(0,0,0,0.12), 0 8px 20px rgba(0,0,0,0.06);
  --ease-out: cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ===== Reset & Base ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
body {
  font-family: var(--font-body);
  color: var(--color-text);
  line-height: 1.6;
  background: var(--color-bg);
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ===== Scroll Animations ===== */
[data-animate] {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.8s var(--ease-out), transform 0.8s var(--ease-out);
}
[data-animate].in-view {
  opacity: 1;
  transform: translateY(0);
}
[data-animate][data-delay="1"] { transition-delay: 0.1s; }
[data-animate][data-delay="2"] { transition-delay: 0.2s; }
[data-animate][data-delay="3"] { transition-delay: 0.3s; }
[data-animate][data-delay="4"] { transition-delay: 0.4s; }
[data-animate][data-delay="5"] { transition-delay: 0.5s; }

/* ===== Header ===== */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: transparent;
  border-bottom: 1px solid transparent;
  height: 52px;
  transition: background 0.35s, border-color 0.35s, box-shadow 0.35s;
}
.site-header.scrolled {
  background: rgba(255,255,255,0.78);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom-color: rgba(0,0,0,0.06);
}
.header-inner {
  max-width: 1120px; margin: 0 auto; padding: 0 32px;
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.logo {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--font-display); font-weight: 700; font-size: 17px;
  color: #fff; transition: color 0.35s;
}
.site-header.scrolled .logo { color: var(--color-text); }
.logo img { width: 32px; height: 32px; border-radius: var(--radius-sm); }
.nav { display: flex; align-items: center; gap: 32px; }
.nav a {
  font-size: 13px; font-weight: 500;
  color: rgba(255,255,255,0.7);
  position: relative; transition: color 0.25s;
}
.site-header.scrolled .nav a { color: var(--color-text-secondary); }
.nav a::after {
  content: ''; position: absolute; bottom: -2px; left: 0; width: 0; height: 1.5px;
  background: var(--color-primary); transition: width 0.25s var(--ease-out);
}
.nav a:hover { color: #fff; }
.site-header.scrolled .nav a:hover { color: var(--color-text); }
.nav a:hover::after { width: 100%; }
.nav-cta {
  padding: 6px 16px; border-radius: var(--radius-pill);
  background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.25);
  font-size: 12px !important; color: #fff !important;
  transition: background 0.25s, border-color 0.25s;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover { background: rgba(255,255,255,0.25); border-color: rgba(255,255,255,0.4); }
.site-header.scrolled .nav-cta {
  background: var(--color-primary); border-color: var(--color-primary);
  color: #fff !important;
}
.site-header.scrolled .nav-cta:hover { background: var(--color-primary-dark); }

/* ===== Hero ===== */
.hero {
  position: relative; min-height: 680px; display: flex; align-items: center; justify-content: center;
  text-align: center; color: #fff; padding: 140px 24px 100px;
  background: linear-gradient(180deg, #0a0e1a 0%, #0f1729 40%, #132040 100%);
  overflow: hidden;
}
/* Perspective grid lines — evokes a road vanishing into the horizon */
.hero::before {
  content: ''; position: absolute; inset: 0;
  background:
    /* Vertical perspective lines */
    linear-gradient(90deg, rgba(0,113,227,0.06) 1px, transparent 1px),
    /* Horizontal grid lines */
    linear-gradient(0deg, rgba(0,113,227,0.04) 1px, transparent 1px);
  background-size: 80px 60px;
  mask-image: linear-gradient(180deg, transparent 0%, rgba(0,0,0,0.5) 40%, rgba(0,0,0,1) 100%);
  -webkit-mask-image: linear-gradient(180deg, transparent 0%, rgba(0,0,0,0.5) 40%, rgba(0,0,0,1) 100%);
}
/* Center glow + subtle road-like converging lines */
.hero::after {
  content: ''; position: absolute; inset: 0;
  background:
    /* Central glow */
    radial-gradient(ellipse 70% 50% at 50% 45%, rgba(0,113,227,0.12) 0%, transparent 60%),
    /* Road center-line glow */
    linear-gradient(180deg, transparent 0%, rgba(0,113,227,0.06) 50%, transparent 100%),
    /* Top horizon haze */
    radial-gradient(ellipse 100% 30% at 50% 0%, rgba(30,60,120,0.3) 0%, transparent 70%);
  pointer-events: none;
}
.hero-content { position: relative; max-width: 720px; }
.hero h1 {
  font-family: var(--font-display);
  font-size: 4em; font-weight: 800; letter-spacing: -0.03em;
  margin-bottom: 16px; line-height: 1.1;
  background: linear-gradient(135deg, #fff 0%, rgba(255,255,255,0.8) 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero p {
  font-size: 1.15em; opacity: 0.7; margin-bottom: 40px;
  line-height: 1.7; font-weight: 400; letter-spacing: 0.01em;
}
.hero-badge {
  display: inline-block; padding: 6px 18px; border-radius: var(--radius-pill);
  background: rgba(255,255,255,0.1); backdrop-filter: blur(10px);
  font-size: 13px; font-weight: 500; margin-bottom: 28px;
  border: 1px solid rgba(255,255,255,0.12);
  letter-spacing: 0.03em;
}

/* Hero stagger animation */
.hero-content > * {
  opacity: 0; transform: translateY(20px);
  animation: heroFadeIn 0.9s var(--ease-out) forwards;
}
.hero-content > *:nth-child(1) { animation-delay: 0.1s; }
.hero-content > *:nth-child(2) { animation-delay: 0.25s; }
.hero-content > *:nth-child(3) { animation-delay: 0.4s; }
.hero-content > *:nth-child(4) { animation-delay: 0.55s; }
@keyframes heroFadeIn {
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Buttons ===== */
.btn {
  display: inline-block; padding: 14px 36px; border-radius: var(--radius-pill);
  font-family: var(--font-display); font-size: 15px; font-weight: 600;
  transition: transform 0.25s var(--ease-out), box-shadow 0.25s var(--ease-out);
  cursor: pointer; border: none;
}
.btn:active { transform: scale(0.97); }
.btn-white {
  background: #fff; color: var(--color-primary);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
.btn-white:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(0,0,0,0.15);
}
.btn-ghost {
  background: rgba(255,255,255,0.1); color: #fff;
  border: 1px solid rgba(255,255,255,0.25);
  backdrop-filter: blur(8px);
}
.btn-ghost:hover {
  transform: translateY(-2px);
  background: rgba(255,255,255,0.18);
  box-shadow: 0 8px 28px rgba(0,0,0,0.15);
}
.hero-btns {
  display: flex; gap: 14px; justify-content: center; flex-wrap: wrap;
}

/* ===== Section ===== */
.section {
  padding: 100px 24px; position: relative;
}
.section-title {
  text-align: center; font-family: var(--font-display);
  font-size: 2.2em; font-weight: 700; margin-bottom: 12px;
  letter-spacing: -0.02em; color: var(--color-text);
}
.section-sub {
  text-align: center; font-size: 1.05em; color: var(--color-text-tertiary);
  margin-bottom: 56px; max-width: 520px; margin-left: auto; margin-right: auto;
  line-height: 1.7;
}
.section-gray {
  background: var(--color-bg-secondary);
  position: relative;
}
.section-gray::before {
  content: ''; position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
}

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
  max-width: 1120px; margin: 0 auto;
}
.feature-card {
  background: var(--color-bg); border-radius: var(--radius-lg); padding: 36px 28px;
  text-align: center; border: 1px solid var(--color-border-light);
  transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), border-color 0.3s;
}
.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.feature-card-img {
  width: 64px; height: 64px; margin: 0 auto 20px;
  background: linear-gradient(135deg, var(--color-primary-light) 0%, #f0f7ff 100%);
  border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.feature-card-img img { width: 36px; height: 36px; object-fit: contain; }
.feature-card h3 {
  font-family: var(--font-display); font-size: 1.1em; font-weight: 700;
  margin-bottom: 8px; color: var(--color-text);
}
.feature-card p {
  font-size: 0.88em; color: var(--color-text-tertiary); line-height: 1.65;
}

/* ===== Advantage ===== */
.adv-row {
  display: flex; align-items: center; gap: 64px;
  max-width: 1120px; margin: 0 auto 72px;
}
.adv-row:last-child { margin-bottom: 0; }
.adv-row.reverse { flex-direction: row-reverse; }
.adv-img {
  flex: 1; border-radius: var(--radius-xl); overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.adv-img img { width: 100%; display: block; transition: transform 0.6s var(--ease-out); }
.adv-img:hover img { transform: scale(1.03); }
.adv-text { flex: 1; }
.adv-text h3 {
  font-family: var(--font-display); font-size: 1.7em; font-weight: 700;
  margin-bottom: 16px; letter-spacing: -0.02em; color: var(--color-text);
}
.adv-text p {
  color: var(--color-text-tertiary); font-size: 1em; line-height: 1.8;
}

/* ===== Audience ===== */
.audience-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  max-width: 1120px; margin: 0 auto;
}
.audience-card {
  text-align: center; padding: 36px 20px; border-radius: var(--radius-lg);
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), border-color 0.3s;
}
.audience-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}
.audience-icon-wrap {
  width: 56px; height: 56px; margin: 0 auto 16px;
  background: linear-gradient(135deg, var(--color-primary-light) 0%, #f0f7ff 100%);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 1.5em;
}
.audience-card h4 {
  font-family: var(--font-display); font-weight: 700; margin-bottom: 4px;
  font-size: 1em;
}
.audience-card p { font-size: 0.88em; color: var(--color-text-tertiary); }

/* ===== CTA ===== */
.cta-section {
  text-align: center; padding: 100px 24px;
  background: linear-gradient(180deg, #000 0%, #1a1a2e 50%, #16213e 100%);
  color: #fff; position: relative; overflow: hidden;
}
.cta-section::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(ellipse 60% 50% at 50% 50%, rgba(0,113,227,0.12) 0%, transparent 70%);
  pointer-events: none;
}
.cta-section h2 {
  font-family: var(--font-display); font-size: 2.4em; font-weight: 700;
  margin-bottom: 16px; letter-spacing: -0.02em; position: relative;
}
.cta-section > p {
  opacity: 0.6; margin-bottom: 40px; font-size: 1.05em; position: relative;
}

/* ===== Download Buttons ===== */
.download-buttons {
  display: flex; gap: 14px; justify-content: center; flex-wrap: wrap;
  margin-bottom: 28px; position: relative;
}
.btn-download {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 14px 30px; border-radius: var(--radius-pill);
  font-family: var(--font-display); font-size: 14px; font-weight: 600;
  transition: transform 0.25s var(--ease-out), box-shadow 0.25s var(--ease-out);
  cursor: pointer;
}
.btn-download:active { transform: scale(0.97); }
.btn-download svg { width: 18px; height: 18px; }
.btn-download:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(0,0,0,0.2);
}
.btn-android {
  background: #fff; color: var(--color-primary);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
.btn-ios {
  background: rgba(255,255,255,0.12); color: #fff;
  border: 1px solid rgba(255,255,255,0.2);
  backdrop-filter: blur(10px);
}
.download-tip {
  font-size: 13px; opacity: 0.5; margin: 0; position: relative;
  letter-spacing: 0.01em;
}

/* ===== Modal ===== */
.modal-overlay {
  position: fixed; inset: 0; z-index: 200;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.32);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  opacity: 0; visibility: hidden; transition: opacity 0.35s, visibility 0.35s;
}
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal-card {
  background: rgba(255,255,255,0.96);
  backdrop-filter: blur(40px);
  -webkit-backdrop-filter: blur(40px);
  border-radius: var(--radius-xl); padding: 44px 40px 36px;
  max-width: 380px; width: 90%; text-align: center;
  box-shadow: var(--shadow-xl);
  transform: translateY(24px) scale(0.94);
  transition: transform 0.4s var(--ease-spring);
  border: 1px solid rgba(255,255,255,0.5);
}
.modal-overlay.active .modal-card { transform: translateY(0) scale(1); }
.modal-icon {
  width: 60px; height: 60px; margin: 0 auto 22px;
  background: linear-gradient(135deg, var(--color-primary) 0%, #3d85fa 100%);
  border-radius: 16px; display: flex; align-items: center; justify-content: center;
  color: #fff; box-shadow: 0 8px 24px rgba(0,113,227,0.25);
}
.modal-icon svg { width: 28px; height: 28px; }
.modal-card h3 {
  font-family: var(--font-display); font-size: 1.15em; font-weight: 700;
  margin-bottom: 10px; color: var(--color-text);
}
.modal-card > p {
  font-size: 0.92em; color: var(--color-text-tertiary); margin-bottom: 22px;
  line-height: 1.7;
}
.modal-card > p strong { color: var(--color-primary); font-weight: 600; }
.modal-search {
  display: flex; align-items: center; justify-content: center; gap: 12px;
  background: var(--color-bg-secondary); border-radius: var(--radius-md);
  padding: 14px 18px; margin-bottom: 28px;
}
.modal-search-label { font-size: 13px; color: var(--color-text-tertiary); }
.modal-search-value {
  font-family: var(--font-display); font-size: 17px; font-weight: 700;
  color: var(--color-primary); letter-spacing: 0.02em;
}
.btn-modal-close {
  display: inline-block; width: 100%; padding: 14px 0;
  border-radius: var(--radius-pill);
  background: var(--color-primary); color: #fff;
  font-family: var(--font-display); font-size: 15px; font-weight: 600;
  border: none; cursor: pointer;
  transition: transform 0.25s var(--ease-out), box-shadow 0.25s var(--ease-out), background 0.2s;
}
.btn-modal-close:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(0,113,227,0.3);
  background: var(--color-primary-dark);
}
.btn-modal-close:active { transform: scale(0.98); }

/* ===== Footer ===== */
.site-footer {
  background: #111; color: var(--color-text-tertiary);
  padding: 52px 24px 36px;
}
.footer-inner {
  max-width: 1120px; margin: 0 auto;
  display: flex; justify-content: space-between; align-items: flex-start;
  flex-wrap: wrap; gap: 32px;
}
.footer-brand { max-width: 320px; }
.footer-brand strong {
  font-family: var(--font-display); font-size: 16px; color: #fff;
  font-weight: 700;
}
.footer-brand p { margin-top: 12px; font-size: 13px; line-height: 1.9; }
.footer-brand a { color: var(--color-primary); transition: opacity 0.2s; }
.footer-brand a:hover { opacity: 0.8; }
.footer-links h4 {
  font-family: var(--font-display); color: #fff; font-size: 12px;
  font-weight: 600; margin-bottom: 14px;
  text-transform: uppercase; letter-spacing: 0.06em;
}
.footer-links a {
  display: block; font-size: 13px; margin-bottom: 10px;
  color: var(--color-text-tertiary); transition: color 0.2s;
  position: relative;
}
.footer-links a:hover { color: #fff; }
.footer-bottom {
  max-width: 1120px; margin: 36px auto 0; padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.08);
  text-align: center; font-size: 12px; color: #48484a;
}
.footer-bottom a { color: #48484a; transition: color 0.2s; }
.footer-bottom a:hover { color: var(--color-primary); }

/* ===== Support Page ===== */
.page-title {
  text-align: center; padding: 130px 24px 70px;
  background: var(--color-bg-secondary);
  position: relative;
}
.page-title::before {
  content: ''; position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
}
.page-title h1 {
  font-family: var(--font-display); font-size: 2.6em; font-weight: 800;
  letter-spacing: -0.03em; position: relative;
}
.page-title p {
  color: var(--color-text-tertiary); margin-top: 10px; font-size: 1.05em;
  position: relative;
}
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  border-bottom: 1px solid var(--color-border-light);
  overflow: hidden;
}
.faq-q {
  display: flex; justify-content: space-between; align-items: center;
  padding: 22px 0; cursor: pointer;
  font-family: var(--font-display); font-weight: 600; font-size: 1.05em;
  color: var(--color-text); transition: color 0.2s;
  user-select: none;
}
.faq-q:hover { color: var(--color-primary); }
.faq-q::after {
  content: '+'; font-size: 1.3em; color: var(--color-text-tertiary);
  transition: transform 0.35s var(--ease-out), color 0.2s;
  font-weight: 300;
}
.faq-item.open .faq-q::after {
  transform: rotate(45deg); color: var(--color-primary);
}
.faq-a {
  max-height: 0; overflow: hidden; color: var(--color-text-tertiary);
  line-height: 1.85; font-size: 0.95em;
  transition: max-height 0.4s var(--ease-out), padding 0.3s;
  padding: 0;
}
.faq-item.open .faq-a {
  max-height: 400px; padding: 0 0 24px;
}
.contact-cards {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px;
  max-width: 680px; margin: 0 auto;
}
.contact-card-item {
  background: var(--color-bg); border-radius: var(--radius-xl);
  padding: 36px 28px; text-align: center;
  border: 1px solid var(--color-border-light);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease-out), box-shadow 0.3s;
}
.contact-card-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.contact-card-icon {
  width: 48px; height: 48px; margin: 0 auto 16px;
  background: linear-gradient(135deg, var(--color-primary-light) 0%, #f0f7ff 100%);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  color: var(--color-primary);
}
.contact-card-icon svg { width: 22px; height: 22px; }
.contact-card-item h4 {
  font-family: var(--font-display); font-weight: 700; font-size: 1em;
  margin-bottom: 6px; color: var(--color-text);
}
.contact-name {
  font-size: 0.92em; color: var(--color-text-tertiary); margin-bottom: 12px;
}
.contact-link {
  display: block; font-size: 0.88em; color: var(--color-primary);
  font-weight: 500; transition: opacity 0.2s; margin-bottom: 4px;
}
.contact-link:last-child { margin-bottom: 0; }
.contact-link:hover { opacity: 0.7; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .site-header { height: 48px; }
  .header-inner { padding: 0 20px; }
  .nav { gap: 20px; }
  .nav a { font-size: 12px; }
  .hero { min-height: 560px; padding: 120px 20px 80px; }
  .hero h1 { font-size: 2.8em; }
  .hero p { font-size: 1em; }
  .section { padding: 72px 20px; }
  .section-title { font-size: 1.8em; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); gap: 14px; }
  .audience-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .adv-row, .adv-row.reverse { flex-direction: column; gap: 36px; }
  .adv-text h3 { font-size: 1.4em; }
  .contact-cards { grid-template-columns: 1fr; gap: 14px; }
  .footer-inner { flex-direction: column; }
  .download-buttons { flex-direction: column; align-items: center; }
  .btn-download { width: 100%; max-width: 280px; justify-content: center; }
  .page-title { padding: 110px 20px 50px; }
  .page-title h1 { font-size: 2em; }
}
@media (max-width: 480px) {
  .feature-grid { grid-template-columns: 1fr; }
  .audience-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 2.2em; }
  .cta-section h2 { font-size: 1.8em; }
}

/* ===== Changelog ===== */
.nav a.active { color: #fff; }
.nav a.active::after { width: 100%; }
.site-header.scrolled .nav a.active { color: var(--color-primary); }

.changelog-section {
  padding: 80px 24px 120px;
  background: var(--color-bg);
}
.changelog-list {
  max-width: 720px;
  margin: 0 auto;
  position: relative;
}
.changelog-list::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: var(--color-border-light);
}
.changelog-item {
  position: relative;
  padding: 0 0 32px 36px;
}
.changelog-item:last-child { padding-bottom: 0; }
.changelog-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 18px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 3px solid var(--color-border);
  z-index: 1;
  transition: border-color 0.3s, background 0.3s;
}
.changelog-item.is-latest::before {
  border-color: var(--color-primary);
  background: var(--color-primary);
  box-shadow: 0 0 0 4px rgba(0, 113, 227, 0.15);
}
.changelog-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 28px 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.3s var(--ease-out), transform 0.3s var(--ease-out);
}
.changelog-item.is-latest .changelog-card {
  border: 2px solid var(--color-primary);
  box-shadow: 0 8px 28px rgba(0, 113, 227, 0.12);
}
.changelog-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.changelog-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 6px;
}
.changelog-version {
  font-family: var(--font-display);
  font-size: 1.6em;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.01em;
}
.changelog-badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--color-primary);
  color: #fff;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 600;
  border-radius: var(--radius-pill);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.changelog-date {
  font-size: 14px;
  color: var(--color-text-tertiary);
  margin-bottom: 18px;
}
.changelog-changes {
  list-style: none;
  padding: 0;
  margin: 0 0 24px;
}
.changelog-changes li {
  position: relative;
  padding: 6px 0 6px 22px;
  font-size: 0.95em;
  line-height: 1.7;
  color: var(--color-text);
}
.changelog-changes li::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 16px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
}
.changelog-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  background: #10b981;
  color: #fff;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 600;
  transition: background 0.2s, transform 0.2s var(--ease-out);
}
.changelog-download:hover {
  background: #059669;
  transform: translateY(-1px);
}
.changelog-download:active { transform: scale(0.97); }
.changelog-download svg { width: 16px; height: 16px; }

.changelog-empty,
.changelog-error {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  padding: 60px 24px;
  color: var(--color-text-tertiary);
  font-size: 0.95em;
}
.changelog-error { color: #dc2626; }

.changelog-skeleton {
  max-width: 720px;
  margin: 0 auto;
}
.changelog-skeleton-item {
  height: 180px;
  background: linear-gradient(90deg, var(--color-bg-secondary) 0%, #ececef 50%, var(--color-bg-secondary) 100%);
  background-size: 200% 100%;
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
  animation: skeletonShimmer 1.4s ease-in-out infinite;
}
@keyframes skeletonShimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.cta-history-link {
  display: inline-block;
  margin-top: 18px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.3);
  padding-bottom: 2px;
  transition: color 0.2s, border-color 0.2s;
}
.cta-history-link:hover {
  color: #fff;
  border-color: #fff;
}
.cta-history-link::after {
  content: ' →';
  transition: transform 0.2s;
  display: inline-block;
}
.cta-history-link:hover::after { transform: translateX(3px); }

@media (max-width: 768px) {
  .changelog-section { padding: 60px 20px 80px; }
  .changelog-card { padding: 22px 20px 20px; }
  .changelog-version { font-size: 1.3em; }
  .changelog-download { width: 100%; justify-content: center; }
  .changelog-list::before { left: 6px; }
  .changelog-item { padding-left: 32px; }
  .changelog-item::before { width: 14px; height: 14px; }
}