:root {
  --bg: #061018;
  --bg-2: #0a1a24;
  --ink: #e8f4f0;
  --muted: #8aa39a;
  --accent: #4de8ff;
  --accent-2: #8b6cff;
  --line: rgba(232, 244, 240, 0.12);
  --glass: rgba(10, 26, 36, 0.55);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
}

@media (max-width: 960px) {
  html {
    scroll-behavior: auto;
  }
}

body {
  min-height: 100vh;
  font-family: "Manrope", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(1200px 700px at 80% -10%, rgba(77, 232, 255, 0.14), transparent 55%),
    radial-gradient(900px 600px at 10% 20%, rgba(139, 108, 255, 0.14), transparent 50%),
    linear-gradient(165deg, #041016 0%, #081820 45%, #061018 100%);
  overflow-x: hidden;
  -webkit-overflow-scrolling: touch;
}

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

.noise {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 1;
  opacity: 0.045;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  contain: strict;
}

#field {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
  contain: strict;
  transform: translateZ(0);
}

.top,
main,
.foot {
  position: relative;
  z-index: 2;
}

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem clamp(1.25rem, 4vw, 3.5rem);
  max-width: 1280px;
  margin: 0 auto;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.logo-text strong {
  font-family: "Syne", "Manrope", sans-serif;
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: 0.06em;
}

.logo-text small {
  font-size: 0.68rem;
  color: var(--muted);
  letter-spacing: 0.04em;
  font-weight: 500;
}

.logo-mark {
  width: 2.35rem;
  height: 2.35rem;
  object-fit: contain;
  flex-shrink: 0;
  filter: drop-shadow(0 0 12px rgba(77, 232, 255, 0.25));
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.92rem;
  font-weight: 500;
}

.nav a {
  opacity: 0.75;
  transition: opacity 0.25s ease, color 0.25s ease;
}

.nav a:hover {
  opacity: 1;
  color: var(--accent);
}

.nav-cta {
  opacity: 1 !important;
  padding: 0.55rem 1rem;
  border: 1px solid var(--line);
  border-radius: 0.65rem;
  background: rgba(255, 255, 255, 0.03);
}

.nav-cta:hover {
  border-color: rgba(77, 232, 255, 0.45);
  color: var(--accent) !important;
}

.hero {
  min-height: calc(100vh - 72px);
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: clamp(2rem, 5vw, 4rem);
  max-width: 1280px;
  margin: 0 auto;
  padding: clamp(1rem, 3vw, 2rem) clamp(1.25rem, 4vw, 3.5rem) 4rem;
}

.brand {
  font-family: "Syne", "Manrope", sans-serif;
  font-weight: 800;
  font-size: clamp(2.8rem, 7.5vw, 5.2rem);
  line-height: 1.05;
  letter-spacing: 0.02em;
  background: linear-gradient(120deg, #ffffff 18%, var(--accent) 58%, #8b6cff 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 0.35rem;
}

.brand-en {
  font-family: "Syne", sans-serif;
  font-weight: 700;
  font-size: clamp(0.95rem, 1.6vw, 1.15rem);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.15rem;
  opacity: 0.9;
}

.headline {
  font-family: "Syne", "Manrope", sans-serif;
  font-weight: 700;
  font-size: clamp(1.35rem, 2.8vw, 1.95rem);
  line-height: 1.35;
  letter-spacing: 0.01em;
  max-width: 16em;
  margin-bottom: 1rem;
}

.sub {
  color: var(--muted);
  font-size: clamp(1rem, 1.5vw, 1.15rem);
  line-height: 1.65;
  max-width: 28em;
  margin-bottom: 2rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.85rem 1.1rem;
}

.cta-note {
  font-size: 0.85rem;
  color: var(--muted);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.95rem 1.35rem;
  border-radius: 0.75rem;
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform 0.35s var(--ease), background 0.25s ease, border-color 0.25s ease, color 0.25s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, #4de8ff, #6d8cff);
  color: #041018;
}

.btn-primary:hover {
  background: linear-gradient(135deg, #7af0ff, #8ea0ff);
}

.btn-ghost {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: rgba(139, 108, 255, 0.55);
  color: #c4b5ff;
}

.hero-stage {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 520px;
}

.orbit {
  position: absolute;
  width: min(92%, 460px);
  aspect-ratio: 1;
  border-radius: 50%;
  border: 1px solid rgba(77, 232, 255, 0.2);
  background:
    radial-gradient(circle at 30% 30%, rgba(77, 232, 255, 0.18), transparent 45%),
    radial-gradient(circle at 70% 65%, rgba(139, 108, 255, 0.18), transparent 40%);
  animation: orbit-spin 18s linear infinite;
}

.orbit::before,
.orbit::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  border: 1px dashed rgba(232, 244, 240, 0.12);
}

.orbit::before {
  inset: 12%;
  animation: orbit-spin 26s linear infinite reverse;
}

.orbit::after {
  inset: 26%;
}

@keyframes orbit-spin {
  to { transform: rotate(360deg); }
}

.phone {
  position: relative;
  width: min(280px, 72vw);
  animation: float-y 5.5s ease-in-out infinite;
  will-change: transform;
}

@keyframes float-y {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-14px); }
}

.phone-bezel {
  border-radius: 2rem;
  padding: 0.55rem;
  background: linear-gradient(160deg, #1c2c34, #0b141a 60%, #15242c);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.45);
}

.phone-notch {
  width: 38%;
  height: 0.7rem;
  margin: 0.15rem auto 0.55rem;
  border-radius: 999px;
  background: #050b10;
}

.screen {
  border-radius: 1.45rem;
  background:
    linear-gradient(180deg, rgba(77, 232, 255, 0.08), transparent 28%),
    #09151c;
  min-height: 460px;
  padding: 1rem 0.9rem 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  overflow: hidden;
}

.chat-top {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: #cfe8df;
  padding: 0.35rem 0.2rem 0.7rem;
  border-bottom: 1px solid var(--line);
}

.chat-avatar {
  width: 1.35rem;
  height: 1.35rem;
  object-fit: contain;
  border-radius: 0.3rem;
}

.dot {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0 rgba(77, 232, 255, 0.5);
  animation: pulse-dot 2s ease infinite;
}

@keyframes pulse-dot {
  0%, 100% { box-shadow: 0 0 0 0 rgba(77, 232, 255, 0.45); }
  50% { box-shadow: 0 0 0 8px rgba(77, 232, 255, 0); }
}

.bubbles {
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
  flex: 1;
}

.bubble {
  max-width: 88%;
  padding: 0.7rem 0.85rem;
  border-radius: 1rem;
  font-size: 0.8rem;
  line-height: 1.5;
  opacity: 0;
  transform: translateY(10px);
  animation: bubble-in 0.6s var(--ease) forwards;
}

.bubble.in {
  align-self: flex-start;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--line);
  border-bottom-left-radius: 0.35rem;
  animation-delay: 0.6s;
}

.bubble.out {
  align-self: flex-end;
  background: linear-gradient(135deg, rgba(77, 232, 255, 0.92), rgba(109, 140, 255, 0.95));
  color: #041018;
  font-weight: 600;
  border-bottom-right-radius: 0.35rem;
  animation-delay: 1.1s;
}

.bubble.in:nth-child(3) {
  animation-delay: 1.7s;
}

.bubble.typing {
  animation-delay: 2.3s;
  display: inline-flex;
  gap: 0.28rem;
  align-items: center;
  min-width: 3.2rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--line);
  color: transparent;
}

.bubble.typing span {
  width: 0.35rem;
  height: 0.35rem;
  border-radius: 50%;
  background: var(--muted);
  animation: typing 1.2s ease-in-out infinite;
}

.bubble.typing span:nth-child(2) { animation-delay: 0.15s; }
.bubble.typing span:nth-child(3) { animation-delay: 0.3s; }

@keyframes bubble-in {
  to { opacity: 1; transform: translateY(0); }
}

@keyframes typing {
  0%, 100% { opacity: 0.3; transform: translateY(0); }
  50% { opacity: 1; transform: translateY(-3px); }
}

.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

.reveal.show {
  opacity: 1;
  transform: translateY(0);
}

.features {
  max-width: 1100px;
  margin: 0 auto;
  padding: 5.5rem clamp(1.25rem, 4vw, 3.5rem) 3rem;
}

.section-head {
  margin-bottom: 2.75rem;
  max-width: 28rem;
}

.section-head h2 {
  font-family: "Syne", sans-serif;
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  letter-spacing: -0.03em;
  margin-bottom: 0.75rem;
}

.section-head p {
  color: var(--muted);
  line-height: 1.65;
}

.feature-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  border-top: 1px solid var(--line);
}

.feature-list li {
  padding: 1.75rem 0.25rem 0.5rem;
  border-right: 1px solid var(--line);
}

.feature-list li:last-child {
  border-right: none;
}

.feat-num {
  display: block;
  font-family: "Syne", sans-serif;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: 0.06em;
}

.feature-list h3 {
  font-family: "Syne", sans-serif;
  font-size: 1.25rem;
  margin-bottom: 0.55rem;
}

.feature-list p {
  color: var(--muted);
  line-height: 1.6;
  font-size: 0.95rem;
}

.download {
  padding: 3rem clamp(1.25rem, 4vw, 3.5rem) 5rem;
}

.download-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: clamp(2.5rem, 5vw, 4rem);
  border: 1px solid var(--line);
  border-radius: 1.75rem;
  background:
    radial-gradient(600px 280px at 15% 0%, rgba(77, 232, 255, 0.12), transparent 55%),
    radial-gradient(500px 260px at 90% 100%, rgba(139, 108, 255, 0.12), transparent 50%),
    rgba(8, 20, 28, 0.7);
  text-align: center;
}

.download-inner h2 {
  font-family: "Syne", sans-serif;
  font-size: clamp(1.9rem, 3.5vw, 2.8rem);
  letter-spacing: -0.03em;
  margin-bottom: 0.7rem;
}

.download-inner > p {
  color: var(--muted);
  margin-bottom: 2rem;
}

.platforms {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.platform {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  min-width: 260px;
  padding: 1.05rem 1.35rem;
  border-radius: 1rem;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
  text-align: left;
  transition: transform 0.35s var(--ease), border-color 0.25s ease, background 0.25s ease;
}

.platform-primary {
  border-color: rgba(77, 232, 255, 0.35);
  background: rgba(77, 232, 255, 0.1);
}

.platform:hover {
  transform: translateY(-3px);
  border-color: rgba(77, 232, 255, 0.55);
  background: rgba(77, 232, 255, 0.14);
}

.download-remark {
  color: var(--ink);
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 32em;
  margin: 0 auto 1rem;
  white-space: pre-wrap;
  opacity: 0.88;
}

.download-tip {
  color: var(--muted);
  font-size: 0.85rem;
  line-height: 1.55;
  max-width: 28em;
  margin: 0 auto;
}

.platform small {
  display: block;
  font-size: 0.7rem;
  color: var(--muted);
}

.platform strong {
  font-family: "Syne", sans-serif;
  font-size: 1.1rem;
}

.platform-icon {
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 0.55rem;
  background: #0d1b22;
  position: relative;
}

.platform-icon.android::before {
  content: "";
  position: absolute;
  inset: 0.5rem 0.55rem 0.4rem;
  border: 2px solid var(--accent);
  border-radius: 0.35rem 0.35rem 0.45rem 0.45rem;
}

.foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  max-width: 1280px;
  margin: 0 auto;
  padding: 1.5rem clamp(1.25rem, 4vw, 3.5rem) 2.5rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--line);
}

.foot-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: "Syne", "Manrope", sans-serif;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.foot-brand img {
  width: 1.75rem;
  height: 1.75rem;
  object-fit: contain;
}

.toast {
  position: fixed;
  left: 50%;
  bottom: 1.5rem;
  transform: translateX(-50%) translateY(120%);
  z-index: 20;
  padding: 0.85rem 1.2rem;
  border-radius: 0.75rem;
  background: rgba(6, 22, 18, 0.92);
  border: 1px solid rgba(77, 232, 255, 0.35);
  color: var(--ink);
  font-size: 0.9rem;
  backdrop-filter: blur(10px);
  transition: transform 0.45s var(--ease);
  pointer-events: none;
}

.toast.show {
  transform: translateX(-50%) translateY(0);
}

@media (max-width: 960px) {
  /* feTurbulence 全屏噪点在移动端滚动时极耗 GPU */
  .noise {
    display: none;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 1.5rem;
    text-align: center;
  }

  .headline,
  .sub {
    max-width: none;
    margin-left: auto;
    margin-right: auto;
  }

  .cta-row {
    justify-content: center;
    flex-direction: column;
  }

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

  /* 滚动时少叠旋转层，改静态光晕 */
  .orbit {
    animation: none;
  }

  .orbit::before {
    animation: none;
  }

  .phone {
    animation: none;
    will-change: auto;
  }

  .bubble.typing span {
    animation: none;
    opacity: 0.55;
  }

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

  .feature-list li {
    border-right: none;
    border-bottom: 1px solid var(--line);
    padding: 1.4rem 0;
  }

  .toast {
    backdrop-filter: none;
  }
}

@media (max-width: 560px) {
  .nav a:not(.nav-cta) {
    display: none;
  }

  .brand {
    font-size: clamp(2.4rem, 12vw, 3.4rem);
  }

  .brand-en {
    letter-spacing: 0.12em;
  }

  .foot {
    flex-direction: column;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

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