/* 即刻互传 · 官网 */
@import url("https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700&family=Noto+Sans+SC:wght@400;500;700&display=swap");

:root {
  --mint: #5f8f7e;
  --mint-deep: #3f6b5c;
  --mint-soft: #d7ebe3;
  --teal: #0f8f7f;
  --teal-deep: #0b6b60;
  --ink: #15241f;
  --ink-soft: #4a5c55;
  --paper: #f3f7f5;
  --fog: #e8efeb;
  --white: #ffffff;
  --line: rgba(63, 107, 92, 0.16);
  --ring: rgba(15, 143, 127, 0.32);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --max: 1080px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: "Noto Sans SC", "Outfit", sans-serif;
  background:
    radial-gradient(90% 60% at 100% 0%, rgba(95, 143, 126, 0.18), transparent 55%),
    radial-gradient(70% 50% at 0% 30%, rgba(15, 143, 127, 0.1), transparent 50%),
    linear-gradient(180deg, #eef5f2 0%, var(--paper) 28%, #f7faf8 100%);
  line-height: 1.65;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.28;
  background-image: radial-gradient(circle at 1px 1px, rgba(63, 107, 92, 0.14) 1px, transparent 0);
  background-size: 26px 26px;
  z-index: 0;
}

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

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

.site {
  position: relative;
  z-index: 1;
}

/* —— Topbar —— */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px 24px;
  backdrop-filter: blur(14px);
  background: rgba(243, 247, 245, 0.72);
  border-bottom: 1px solid transparent;
}

.topbar.is-scrolled {
  border-bottom-color: var(--line);
}

.topbar-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: "Outfit", "Noto Sans SC", sans-serif;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--mint-deep);
}

.topbar-brand img {
  width: 28px;
  height: 28px;
  border-radius: 7px;
}

.topbar-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px 18px;
  font-size: 0.9rem;
  color: var(--ink-soft);
}

.topbar-links a:hover {
  color: var(--teal-deep);
}

/* —— Hero —— */
.hero {
  position: relative;
  min-height: calc(100svh - 58px);
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 12px 24px 40px;
  overflow: hidden;
}

.hero-stage {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-stage .radar {
  position: absolute;
  width: min(110vw, 640px);
  aspect-ratio: 1;
  top: 28%;
  left: 50%;
  translate: -50% -55%;
  border-radius: 50%;
  background:
    radial-gradient(circle at center, rgba(255, 255, 255, 0.5) 0 12%, transparent 13%),
    repeating-radial-gradient(
      circle at center,
      transparent 0,
      transparent 64px,
      rgba(63, 107, 92, 0.1) 65px,
      rgba(63, 107, 92, 0.1) 66px
    );
}

.hero-stage .radar::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: conic-gradient(
    from 0deg,
    transparent 0deg,
    rgba(95, 143, 126, 0.28) 50deg,
    transparent 78deg
  );
  animation: sweep 5s linear infinite;
}

.hero-stage .radar::after {
  content: "";
  position: absolute;
  inset: 14%;
  border-radius: 50%;
  border: 1px solid rgba(63, 107, 92, 0.16);
}

.hero-icon {
  position: absolute;
  top: 28%;
  left: 50%;
  width: min(28vw, 132px);
  aspect-ratio: 1;
  border-radius: 32px;
  overflow: hidden;
  box-shadow: 0 22px 40px rgba(21, 36, 31, 0.16);
  transform: translate(-50%, -58%);
  animation: float-y 6s ease-in-out infinite;
}

.hero-icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-copy {
  position: relative;
  z-index: 2;
  width: min(920px, 100%);
  margin: 0 auto;
  text-align: center;
  padding-top: min(26vh, 200px);
  opacity: 0;
  transform: translateY(20px);
  animation: rise-in 0.95s var(--ease) 0.15s forwards;
}

.brand-name {
  margin: 0 0 8px;
  font-family: "Outfit", "Noto Sans SC", sans-serif;
  font-size: clamp(2.4rem, 7vw, 4rem);
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1.02;
  color: var(--mint-deep);
}

.headline {
  margin: 0 0 8px;
  font-size: clamp(1.1rem, 2.4vw, 1.45rem);
  font-weight: 700;
  color: var(--ink);
}

.subhead {
  margin: 0 auto 22px;
  max-width: 32rem;
  font-size: 0.98rem;
  color: var(--ink-soft);
}

.hero-download {
  width: min(880px, 100%);
  margin: 0 auto;
  scroll-margin-top: 72px;
}

.download-hint {
  margin: 0 0 14px;
  font-size: 0.88rem;
  color: var(--ink-soft);
}

.download-hint strong {
  color: var(--mint-deep);
}

.cta-meta {
  margin: 12px 0 0;
  font-size: 0.86rem;
  color: var(--ink-soft);
}

.cta-meta strong {
  color: var(--mint-deep);
  font-weight: 600;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 12px;
  border: 1px solid transparent;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.25s var(--ease), background 0.2s ease, border-color 0.2s ease;
}

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

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

.btn-primary {
  background: linear-gradient(180deg, var(--teal), var(--teal-deep));
  color: var(--white);
}

.btn-primary.is-disabled,
.btn-primary[aria-disabled="true"] {
  opacity: 0.55;
  pointer-events: none;
}

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

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.88);
}

/* —— Sections —— */
.section {
  max-width: var(--max);
  margin: 0 auto;
  padding: 72px 24px;
}

.section-kicker {
  margin: 0 0 10px;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mint);
}

.section h2 {
  margin: 0 0 12px;
  font-size: clamp(1.55rem, 3.2vw, 2.15rem);
  line-height: 1.25;
  color: var(--mint-deep);
}

.section .lead {
  margin: 0;
  max-width: 34rem;
  color: var(--ink-soft);
  font-size: 1.05rem;
}

/* Product showcase — one job */
.showcase {
  padding-top: 24px;
  padding-bottom: 40px;
}

.showcase-frame {
  margin-top: 36px;
  display: grid;
  place-items: center;
}

.phone {
  width: min(100%, 280px);
  border-radius: 36px;
  overflow: hidden;
  border: 1px solid rgba(21, 36, 31, 0.08);
  box-shadow: 0 30px 60px rgba(21, 36, 31, 0.14);
  background: var(--white);
  opacity: 0;
  transform: translateY(24px);
  animation: rise-in 0.9s var(--ease) 0.1s forwards;
}

.phone img {
  width: 100%;
  height: auto;
}

/* Steps — no cards */
.steps {
  margin-top: 40px;
  display: grid;
  gap: 0;
  counter-reset: step;
  border-top: 1px solid var(--line);
}

.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 18px 22px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
  align-items: start;
}

.step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  font-family: "Outfit", sans-serif;
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--mint);
  line-height: 1.2;
  padding-top: 2px;
}

.step h3 {
  margin: 0 0 6px;
  font-size: 1.15rem;
  color: var(--ink);
}

.step p {
  margin: 0;
  color: var(--ink-soft);
}

/* Trust band */
.trust {
  position: relative;
  max-width: none;
  padding: 88px 24px;
  background:
    linear-gradient(120deg, rgba(215, 235, 227, 0.7), rgba(243, 247, 245, 0.2)),
    linear-gradient(180deg, transparent, rgba(95, 143, 126, 0.08));
  border-block: 1px solid var(--line);
  text-align: center;
}

.trust .inner {
  max-width: 720px;
  margin: 0 auto;
}

.trust h2 {
  margin-left: auto;
  margin-right: auto;
}

.trust .lead {
  margin-left: auto;
  margin-right: auto;
}

.trust-visual {
  margin: 36px auto 0;
  width: min(100%, 220px);
  opacity: 0.92;
}

.trust-visual img {
  width: 100%;
  border-radius: 28px;
  box-shadow: 0 18px 40px rgba(21, 36, 31, 0.12);
}

/* Download platforms */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.platform-grid--hero {
  margin-top: 0;
}

.platform {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 14px 14px 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(10px);
  text-align: left;
  transition: transform 0.25s var(--ease), border-color 0.2s ease;
}

.platform:hover {
  transform: translateY(-2px);
  border-color: rgba(15, 143, 127, 0.4);
}

.platform.is-recommended {
  border-color: rgba(15, 143, 127, 0.55);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.95), rgba(215, 235, 227, 0.65));
}

.platform-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.92rem;
  font-weight: 700;
}

.platform-label svg {
  width: 18px;
  height: 18px;
  fill: var(--mint-deep);
  flex-shrink: 0;
}

.platform .btn {
  width: 100%;
  min-height: 40px;
  font-size: 0.9rem;
}

.badge {
  display: inline-block;
  margin-left: 2px;
  padding: 2px 7px;
  border-radius: 6px;
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--mint-deep);
  background: var(--mint-soft);
  vertical-align: middle;
}

/* Footer */
.site-foot {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 24px 56px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  justify-content: space-between;
  font-size: 0.86rem;
  color: var(--ink-soft);
  border-top: 1px solid var(--line);
}

.site-foot a:hover {
  color: var(--teal-deep);
}

@keyframes rise-in {
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes sweep {
  to {
    transform: rotate(360deg);
  }
}

@keyframes float-y {
  0%,
  100% {
    transform: translate(-50%, -58%);
  }
  50% {
    transform: translate(-50%, calc(-58% - 10px));
  }
}

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

  .hero-copy {
    padding-top: min(22vh, 160px);
  }
}

@media (max-width: 560px) {
  .topbar {
    padding-inline: 16px;
  }

  .topbar-links {
    font-size: 0.8rem;
    gap: 6px 12px;
  }

  .hero {
    min-height: auto;
    padding: 8px 16px 28px;
    justify-content: flex-start;
  }

  .hero-copy {
    padding-top: min(20vh, 140px);
  }

  .hero-icon {
    width: min(30vw, 96px);
    border-radius: 24px;
  }

  .platform-grid {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }

  .platform {
    padding: 12px;
  }

  .section {
    padding-inline: 16px;
  }
}

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

  .hero-copy,
  .phone {
    opacity: 1;
    transform: none;
  }
}