:root {
  --bg: #07080d;
  --fg: #f5f7fb;
  --dim: #b7bdd0;
  --faint: #8b93a8;
  --line: rgba(245, 247, 251, 0.12);
  --line-2: rgba(245, 247, 251, 0.22);
  --blue: #8eb4ff;
  --blue-ink: #07101f;
  --paper: #f4f1ea;
  --ink: #12141a;
  --sans: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "SF Pro Display", "Segoe UI", sans-serif;
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --max: 1180px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 68px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.6;
}

body::before {
  content: "";
  position: fixed;
  inset: -20%;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 18% 12%, rgba(90, 130, 255, 0.22), transparent 26%),
    radial-gradient(circle at 82% 18%, rgba(70, 100, 210, 0.16), transparent 24%),
    radial-gradient(circle at 70% 88%, rgba(142, 180, 255, 0.1), transparent 22%),
    radial-gradient(circle, rgba(245, 247, 251, 0.28) 0.6px, transparent 0.7px) 0 0 / 22px 22px;
  animation: mesh 32s ease-in-out infinite alternate;
}

main, .nav { position: relative; z-index: 1; }

a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 40;
  padding: 0.4rem 0.7rem;
  background: var(--paper);
  color: var(--ink);
}

.skip:focus { top: 0.7rem; }

.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 30;
  height: 68px;
  background: rgba(7, 8, 13, 0.72);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(18px);
}

.row {
  width: min(var(--max), calc(100% - 48px));
  height: 68px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 18px;
}

.mark {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1px;
  min-width: 7.5rem;
  line-height: 1.05;
  text-decoration: none;
}

.mark-en {
  color: var(--fg);
  font-size: 16px;
  font-weight: 680;
  letter-spacing: -0.03em;
}

.mark-zh {
  color: var(--faint);
  font-size: 11px;
  font-weight: 550;
  letter-spacing: 0.18em;
}

.nav nav {
  display: flex;
  gap: 2px;
  min-width: 0;
  margin-right: auto;
}

.nav nav a, .foot nav a {
  padding: 8px 10px;
  border-radius: 999px;
  color: var(--dim);
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}

.nav nav a:hover, .foot nav a:hover { color: var(--fg); }

.nav nav a.is-active {
  color: var(--fg);
  background: rgba(142, 180, 255, 0.14);
}

#nav-toggle {
  display: none;
  margin-left: auto;
  padding: 8px 12px;
  border: 1px solid var(--line-2);
  border-radius: 12px;
  background: transparent;
  color: var(--fg);
  font: inherit;
  font-size: 14px;
}

.cta, .ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  padding: 12px 22px;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
}

.cta {
  background: var(--paper);
  color: var(--ink);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.28);
}

.ghost {
  border: 1px solid var(--line-2);
  color: var(--fg);
}

.nav .cta { padding: 9px 16px; font-size: 14px; }

.slide {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 108px 0 72px;
}

.band {
  background:
    linear-gradient(180deg, rgba(142, 180, 255, 0.1), rgba(142, 180, 255, 0.02) 36%, transparent 70%),
    #0c1018;
  box-shadow: inset 0 1px 0 rgba(142, 180, 255, 0.28);
}

.band-ink {
  background: #10131c;
  box-shadow: inset 0 1px 0 rgba(245, 247, 251, 0.08);
}

#pricing {
  background:
    radial-gradient(circle at 78% 0%, rgba(244, 241, 234, 0.08), transparent 34%),
    #141820;
}

#contact { background: #07080d; }

.finale {
  background:
    radial-gradient(circle at 50% 0%, rgba(244, 241, 234, 0.09), transparent 34%),
    #090b10;
}

.wrap { width: min(var(--max), calc(100% - 64px)); margin: 0 auto; }

.center { text-align: center; }

.kicker {
  margin: 0 0 16px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
}

h1, h2, h3 { margin: 0; font-weight: 600; letter-spacing: -0.035em; }

h1 { font-size: clamp(46px, 6.4vw, 84px); line-height: 1.02; }

h2 { font-size: clamp(36px, 4.6vw, 64px); line-height: 1.08; max-width: 16em; }

.center h2 { margin-inline: auto; }

.lead, .cols p, .note, .proof-src, details p {
  color: var(--dim);
  font-size: clamp(16px, 1.5vw, 19px);
  line-height: 1.6;
}

.lead { max-width: 38rem; margin: 22px 0 0; }

.center .lead { margin-inline: auto; }

.btns {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 32px;
}

.hero .cta { padding: 15px 28px; font-size: 16px; }

.more {
  display: inline-block;
  margin-top: 54px;
  color: var(--faint);
  font-size: 13px;
  letter-spacing: 0.16em;
  text-decoration: none;
}

.orbit {
  position: relative;
  height: 220px;
  max-width: 640px;
  margin: 28px auto 8px;
}

.orbit svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.orbit line {
  stroke: rgba(142, 180, 255, 0.45);
  stroke-width: 1.25;
  stroke-dasharray: 4 6;
}

.hub, .sat {
  position: absolute;
  display: grid;
  place-items: center;
  border-radius: 999px;
  transform: translate(-50%, -50%);
}

.hub {
  left: 50%;
  top: 50%;
  width: 108px;
  height: 108px;
  background: radial-gradient(circle at 40% 35%, #d5e4ff, var(--blue) 46%, rgba(142, 180, 255, 0.15) 70%);
  color: var(--blue-ink);
  font-size: 15px;
  font-weight: 700;
  box-shadow: 0 0 40px rgba(142, 180, 255, 0.35);
}

.sat {
  padding: 8px 12px;
  background: #12151e;
  border: 1px solid var(--line-2);
  color: var(--fg);
  font-size: 14px;
  font-weight: 650;
}

.s1 { left: 14%; top: 21%; }
.s2 { left: 14%; top: 79%; }
.s3 { left: 86%; top: 21%; }
.s4 { left: 86%; top: 79%; }

.cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px 32px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.cols.bare { grid-template-columns: repeat(4, 1fr); margin-top: 34px; }

.plans {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin: 36px 0 8px;
  padding: 0;
  list-style: none;
}

.plans li {
  padding: 28px 26px 24px;
  border: 1px solid var(--line-2);
  border-radius: 22px;
  background: rgba(8, 10, 16, 0.5);
}

.plan-name {
  margin: 0;
  color: var(--blue);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.plan-price {
  margin: 12px 0;
  font-size: clamp(40px, 5vw, 64px);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 1;
}

.plans li p:last-child { margin: 0; color: var(--dim); }

.cols span {
  display: block;
  margin-bottom: 10px;
  color: var(--blue);
  font-size: 28px;
  font-weight: 500;
  letter-spacing: 0.04em;
  opacity: 0.85;
}

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

.bare h3::before {
  content: "";
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 10px rgba(142, 180, 255, 0.8);
  vertical-align: 1px;
}

.cols p { margin: 0; font-size: 15px; }

.proof {
  width: min(560px, 100%);
  margin: 32px 0 0;
  padding: 22px 24px;
  border: 1px solid var(--line-2);
  border-radius: 22px;
  background: rgba(8, 10, 16, 0.45);
}

.center .proof, .proof.sync { margin-inline: auto; }

.proof-q { margin: 0; color: var(--faint); font-size: 14px; }

.proof-a { margin: 8px 0; font-size: 22px; letter-spacing: -0.03em; }

.proof-src { margin: 0; font-size: 14px; }

.proof-src i {
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--blue);
}

.url { font-family: var(--mono); font-size: 15px; overflow-wrap: anywhere; }

.pills {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  max-width: 820px;
  margin: 32px auto 0;
  padding: 0;
  list-style: none;
}

.pills li {
  padding: 12px 18px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(245, 247, 251, 0.03);
  font-weight: 650;
}

.note { max-width: 40rem; margin: 22px auto 0; }

details {
  width: min(720px, 100%);
  margin: 28px auto 0;
  text-align: left;
}

summary { cursor: pointer; color: var(--dim); font-weight: 650; }

pre {
  overflow: auto;
  margin: 12px 0;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.28);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.55;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

code { font-family: var(--mono); font-size: 0.92em; }

.finale { padding-bottom: 0; }

.foot {
  margin-top: auto;
  padding: 22px 0 28px;
  border-top: 1px solid var(--line);
  color: var(--faint);
  font-size: 13px;
}

.foot .row { height: auto; min-height: 48px; }

.foot nav { display: flex; gap: 8px; margin-left: auto; flex-wrap: wrap; }

.foot p {
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto 8px;
}

@media (min-width: 900px) {
  html { scroll-snap-type: y proximity; }
  html.is-jumping { scroll-snap-type: none; }
  .slide { scroll-snap-align: start; }
}

@media (max-width: 980px) {
  .cols, .cols.bare { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
  .wrap, .row, .foot p { width: min(var(--max), calc(100% - 32px)); }
  #nav-toggle { display: inline-flex; }
  .nav > .row > .cta { display: none; }
  #nav-panel {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    width: 100%;
    height: calc(100svh - 68px);
    flex-direction: column;
    gap: 4px;
    padding: 12px 8px 24px;
    background: #07080d;
  }
  #nav-panel.open { display: flex; }
  #nav-panel a { font-size: 22px; padding: 12px 16px; }
  h1 { font-size: clamp(40px, 12vw, 56px); }
  h2 { font-size: clamp(32px, 9vw, 44px); }
  .cols, .cols.bare, .plans { grid-template-columns: 1fr; }
  .orbit { height: 200px; }
  .slide { min-height: auto; padding: 108px 0 64px; }
  .hero, .finale { min-height: 100svh; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  body::before { animation: none; }
}

@keyframes mesh {
  from { transform: translate3d(0, 0, 0); }
  to { transform: translate3d(0, -2%, 0) scale(1.04); }
}