/* 即图 AI — Official site */

:root {
  --ink: #12141a;
  --ink-soft: #3a3f4b;
  --muted: #7a8090;
  --paper: #f7f6f9;
  --white: #ffffff;
  --line: rgba(18, 20, 26, 0.08);
  --accent: #8b7cf6;
  --accent-soft: #c4b8ff;
  --blush: #f3c6d8;
  --mist: #d8e8ef;
  --shadow: 0 24px 60px rgba(40, 28, 70, 0.12);
  --radius: 22px;
  --radius-lg: 32px;
  --nav-h: 72px;
  --font: "Noto Sans SC", "Outfit", system-ui, sans-serif;
  --display: "Outfit", "Noto Sans SC", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1, h2, h3 {
  margin: 0;
  line-height: 1.2;
  letter-spacing: -0.02em;
  font-weight: 600;
}

p {
  margin: 0;
}

/* Ambient atmosphere */
.ambient {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.55;
  animation: drift 18s var(--ease) infinite alternate;
}

.orb-a {
  width: 48vw;
  height: 48vw;
  top: -12%;
  left: -8%;
  background: radial-gradient(circle, #e8dffd 0%, transparent 70%);
}

.orb-b {
  width: 40vw;
  height: 40vw;
  top: 8%;
  right: -10%;
  background: radial-gradient(circle, #f8d9e6 0%, transparent 70%);
  animation-delay: -6s;
}

.orb-c {
  width: 36vw;
  height: 36vw;
  bottom: 10%;
  left: 30%;
  background: radial-gradient(circle, #d9ebe8 0%, transparent 70%);
  animation-delay: -12s;
  opacity: 0.4;
}

@keyframes drift {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to { transform: translate3d(3%, 4%, 0) scale(1.08); }
}

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
}

.nav-inner {
  max-width: 1180px;
  margin: 0 auto;
  height: 100%;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 28px;
  backdrop-filter: blur(18px) saturate(1.2);
  -webkit-backdrop-filter: blur(18px) saturate(1.2);
  background: rgba(247, 246, 249, 0.72);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}

.nav.scrolled .nav-inner {
  border-bottom-color: var(--line);
  background: rgba(247, 246, 249, 0.88);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo-mark {
  width: 34px;
  height: 34px;
  border-radius: 11px;
  display: grid;
  place-items: center;
  font-family: var(--display);
  font-weight: 700;
  font-size: 15px;
  color: #fff;
  background: linear-gradient(135deg, #2a2d36 0%, #12141a 55%, #5a4fd6 140%);
  box-shadow: 0 8px 20px rgba(18, 20, 26, 0.18);
}

.logo-text {
  font-family: var(--display);
  font-weight: 650;
  font-size: 18px;
  letter-spacing: 0.02em;
}

.logo-text em {
  font-style: normal;
  font-weight: 500;
  color: var(--muted);
  margin-left: 2px;
}

.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
  font-size: 14px;
  color: var(--ink-soft);
}

.nav-links a {
  position: relative;
  transition: color 0.2s;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -6px;
  height: 2px;
  border-radius: 2px;
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}

.nav-links a:hover {
  color: var(--ink);
}

.nav-links a:hover::after {
  transform: scaleX(1);
}

.nav-cta {
  flex-shrink: 0;
}

.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: 0;
  background: transparent;
  cursor: pointer;
  margin-left: auto;
  padding: 10px;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
}

.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.2s;
}

.nav.open .nav-toggle span:first-child {
  transform: translateY(4px) rotate(45deg);
}

.nav.open .nav-toggle span:last-child {
  transform: translateY(-4px) rotate(-45deg);
}

.nav-drawer {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 12px 24px 20px;
  background: rgba(247, 246, 249, 0.96);
  border-bottom: 1px solid var(--line);
}

.nav-drawer a {
  padding: 12px 0;
  font-size: 16px;
  font-weight: 500;
}

.nav.open .nav-drawer {
  display: flex;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 52px;
  padding: 0 26px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 550;
  letter-spacing: 0.01em;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), background 0.25s;
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-sm {
  height: 40px;
  padding: 0 18px;
  font-size: 13px;
}

.btn-dark {
  background: var(--ink);
  color: #fff;
  box-shadow: 0 12px 28px rgba(18, 20, 26, 0.22);
}

.btn-dark:hover {
  box-shadow: 0 16px 36px rgba(18, 20, 26, 0.28);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--line);
  color: var(--ink);
  backdrop-filter: blur(8px);
}

.btn-ghost:hover {
  background: #fff;
}

.btn-light {
  background: #fff;
  color: var(--ink);
  box-shadow: 0 10px 24px rgba(18, 20, 26, 0.08);
}

/* Layout helpers */
main {
  position: relative;
  z-index: 1;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 16px;
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--accent), var(--blush));
}

.eyebrow.light {
  color: rgba(255, 255, 255, 0.72);
}

.eyebrow.light::before {
  background: linear-gradient(90deg, #fff, var(--accent-soft));
}

.section-head {
  max-width: 640px;
  margin: 0 auto 56px;
  text-align: center;
}

.section-head h2 {
  font-size: clamp(28px, 4vw, 40px);
  margin-bottom: 14px;
}

.section-desc {
  color: var(--muted);
  font-size: 16px;
  font-weight: 400;
}

/* Hero */
.hero {
  max-width: 1180px;
  margin: 0 auto;
  padding: 48px 24px 80px;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 40px;
  align-items: center;
  min-height: calc(100svh - var(--nav-h));
}

.brand-line {
  display: block;
  font-family: var(--display);
  font-size: clamp(56px, 8vw, 88px);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 0.95;
  margin-bottom: 18px;
  background: linear-gradient(120deg, #12141a 20%, #4a3f8c 55%, #b57a9a 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-title {
  display: block;
  font-size: clamp(28px, 3.6vw, 40px);
  font-weight: 600;
  color: var(--ink);
}

.hero-desc {
  margin-top: 20px;
  max-width: 440px;
  color: var(--ink-soft);
  font-size: 16px;
  font-weight: 400;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.hero-stats {
  display: flex;
  gap: 28px;
  margin-top: 44px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero-stats strong {
  font-family: var(--display);
  font-size: 22px;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.hero-stats span {
  font-size: 12px;
  color: var(--muted);
}

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 560px;
}

.phone-stack {
  position: relative;
  width: 100%;
  max-width: 420px;
  height: 560px;
}

.phone {
  margin: 0;
  border-radius: 36px;
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow), 0 0 0 1px rgba(255, 255, 255, 0.7);
  border: 6px solid #1a1c22;
}

.phone img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.phone-back {
  position: absolute;
  width: 58%;
  right: 0;
  top: 36px;
  transform: rotate(8deg);
  opacity: 0.92;
  animation: float-b 7s ease-in-out infinite;
}

.phone-front {
  position: absolute;
  width: 64%;
  left: 0;
  bottom: 0;
  z-index: 2;
  animation: float-a 6.5s ease-in-out infinite;
}

.phone-solo {
  width: min(280px, 70vw);
  aspect-ratio: 9 / 19.2;
}

.phone-solo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
}

@keyframes float-a {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

@keyframes float-b {
  0%, 100% { transform: rotate(8deg) translateY(0); }
  50% { transform: rotate(8deg) translateY(10px); }
}

/* Features */
.features {
  max-width: 1180px;
  margin: 0 auto;
  padding: 40px 24px 100px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.feature-card {
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: var(--radius);
  padding: 28px 24px;
  backdrop-filter: blur(12px);
  box-shadow: 0 10px 30px rgba(40, 28, 70, 0.04);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 18px 40px rgba(40, 28, 70, 0.1);
}

.feature-card-wide {
  grid-column: span 2;
  display: flex;
  align-items: flex-start;
  gap: 20px;
  background:
    linear-gradient(135deg, rgba(232, 223, 253, 0.55), rgba(248, 217, 230, 0.4)),
    rgba(255, 255, 255, 0.75);
}

.feature-icon {
  width: 44px;
  height: 44px;
  color: var(--ink);
  margin-bottom: 18px;
  flex-shrink: 0;
}

.feature-icon svg {
  width: 100%;
  height: 100%;
}

.feature-card-wide .feature-icon {
  margin-bottom: 0;
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.7;
}

/* Showcase */
.showcase {
  max-width: 1180px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

.showcase-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 64px;
  align-items: center;
  padding: 48px 40px;
  margin-bottom: 24px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.65);
  border: 1px solid rgba(255, 255, 255, 0.85);
  box-shadow: 0 12px 40px rgba(40, 28, 70, 0.05);
}

.showcase-row.reverse {
  grid-template-columns: auto 1fr;
}

.showcase-row.reverse .showcase-copy {
  order: 2;
}

.showcase-row.reverse .phone-solo {
  order: 1;
}

.step {
  display: inline-block;
  font-family: var(--display);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--accent);
  margin-bottom: 12px;
}

.showcase-copy h3 {
  font-size: clamp(24px, 3vw, 32px);
  margin-bottom: 14px;
}

.showcase-copy > p {
  color: var(--ink-soft);
  max-width: 460px;
  margin-bottom: 24px;
}

.checklist {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.checklist li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--ink-soft);
}

.checklist li::before {
  content: "";
  width: 18px;
  height: 18px;
  border-radius: 50%;
  flex-shrink: 0;
  background:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none'%3E%3Cpath d='M3.5 8.5l3 3 6-6' stroke='%23fff' stroke-width='1.8' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E")
    center / 12px no-repeat,
    var(--ink);
}

/* Download */
.download {
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 24px 100px;
}

.download-card {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 24px;
  align-items: center;
  padding: 56px 56px 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background:
    radial-gradient(ellipse at 80% 20%, rgba(196, 184, 255, 0.35), transparent 50%),
    radial-gradient(ellipse at 10% 80%, rgba(243, 198, 216, 0.3), transparent 45%),
    linear-gradient(145deg, #1a1c24 0%, #2a2540 55%, #1e2230 100%);
  color: #fff;
  box-shadow: 0 30px 70px rgba(20, 16, 40, 0.28);
}

.download-copy {
  padding-bottom: 56px;
}

.download-copy h2 {
  font-size: clamp(28px, 3.5vw, 40px);
  margin-bottom: 14px;
}

.download-copy > p {
  color: rgba(255, 255, 255, 0.68);
  max-width: 420px;
  margin-bottom: 8px;
}

.download-phones {
  display: flex;
  justify-content: center;
  align-items: flex-end;
}

.download-phones img {
  width: min(260px, 70%);
  border-radius: 28px 28px 0 0;
  border: 5px solid #0e1016;
  border-bottom: 0;
  box-shadow: 0 -10px 40px rgba(0, 0, 0, 0.35);
  transform: translateY(12px);
}

/* Footer */
.footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.5);
}

.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 40px 24px 48px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-brand strong {
  display: block;
  font-size: 15px;
}

.footer-brand p {
  font-size: 13px;
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 24px;
  font-size: 14px;
  color: var(--ink-soft);
}

.footer-links a:hover {
  color: var(--ink);
}

.copyright {
  grid-column: 1 / -1;
  font-size: 12px;
  color: var(--muted);
  padding-top: 8px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
}

.copyright a {
  color: var(--muted);
  transition: color 0.2s;
}

.copyright a:hover {
  color: var(--ink-soft);
}

/* Reveal */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
  transition-delay: var(--d, 0s);
}

.reveal.in {
  opacity: 1;
  transform: none;
}

/* Responsive */
@media (max-width: 980px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 32px;
    text-align: center;
  }

  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .hero-visual {
    min-height: 480px;
    order: -1;
  }

  .phone-stack {
    height: 480px;
    max-width: 360px;
    margin: 0 auto;
  }

  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .feature-card-wide {
    grid-column: span 2;
  }

  .showcase-row,
  .showcase-row.reverse {
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
    padding: 36px 24px;
    gap: 32px;
  }

  .showcase-row.reverse .showcase-copy,
  .showcase-row.reverse .phone-solo {
    order: initial;
  }

  .showcase-copy > p {
    margin-left: auto;
    margin-right: auto;
  }

  .checklist {
    align-items: center;
  }

  .download-card {
    grid-template-columns: 1fr;
    padding: 40px 28px 0;
    text-align: center;
  }

  .download-copy > p {
    margin-left: auto;
    margin-right: auto;
  }

  .download-copy .hero-actions {
    justify-content: center;
  }
}

@media (max-width: 720px) {
  .nav-links,
  .nav-cta {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-stats {
    gap: 16px;
  }

  .hero-stats strong {
    font-size: 18px;
  }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .feature-card-wide {
    grid-column: span 1;
    flex-direction: column;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer-brand {
    justify-content: center;
  }

  .footer-links {
    justify-content: center;
    flex-wrap: wrap;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}