/* Flipped · 怦然心动 — product landing */

:root {
  --brand-cream: #f5f3ee;
  --brand-bg: #f7f6f2;
  --brand-profile: #faf9f6;
  --brand-rose: #e85d75;
  --brand-rose-pressed: #c45c6a;
  --brand-rose-soft: #eeb9c2;
  --brand-rose-tint: #fff5f7;
  --logo-rose: #c99494;
  --logo-sage: #94a388;
  --logo-line: #5e5e57;
  --text-primary: #333333;
  --text-secondary: #666666;
  --text-muted: #999999;
  --border-warm: #ede8e0;
  --white: #ffffff;
  --card-wash: linear-gradient(90deg, #ffffff, #fffcfd, #fff6f8, #fff0f2);
  --font-display: "Noto Serif SC", "Songti SC", "SimSun", serif;
  --font-body: "DM Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    sans-serif;
  --radius-btn: 10px;
  --radius-phone: 28px;
  --shadow-soft: 0 24px 48px rgba(80, 50, 55, 0.08);
  --header-h: 64px;
  --max: 1080px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text-primary);
  background: var(--brand-bg);
  -webkit-font-smoothing: antialiased;
}

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

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

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 100;
  background: var(--brand-rose);
  color: #fff;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-btn);
}

.skip-link:focus {
  top: 1rem;
}

/* Header */
.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(1.25rem, 4vw, 2.5rem);
  background: color-mix(in srgb, var(--brand-cream) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease, background 0.3s ease;
}

.site-header.is-scrolled {
  border-bottom-color: var(--border-warm);
  background: color-mix(in srgb, var(--brand-cream) 94%, transparent);
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
}

.brand-mark img {
  width: 36px;
  height: 36px;
  object-fit: contain;
  border-radius: 50%;
}

.site-nav {
  display: flex;
  gap: 1.25rem;
  font-size: 0.92rem;
  color: var(--text-secondary);
}

.site-nav a:hover {
  color: var(--brand-rose);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 1.35rem;
  border-radius: var(--radius-btn);
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.22s ease, color 0.22s ease, border-color 0.22s ease,
    transform 0.22s ease;
}

.btn-primary {
  background: var(--brand-rose);
  color: #fff;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--brand-rose-pressed);
}

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

.btn-ghost {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border-warm);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--brand-rose-soft);
  color: var(--brand-rose);
}

/* Sections */
.section {
  padding: clamp(4.5rem, 10vw, 7rem) clamp(1.25rem, 4vw, 2.5rem);
}

.section-inner {
  max-width: var(--max);
  margin: 0 auto;
}

.section-inner.narrow {
  max-width: 680px;
  text-align: center;
}

.eyebrow {
  margin: 0 0 0.75rem;
  font-size: 0.85rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--logo-sage);
  font-weight: 500;
}

.section-title {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.75rem, 4vw, 2.4rem);
  line-height: 1.3;
  color: #1a1a1a;
}

.section-lead {
  margin: 0;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.section-lead strong {
  color: var(--brand-rose);
  font-weight: 600;
}

/* Hero */
.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: stretch;
  padding: calc(var(--header-h) + 1.5rem) clamp(1.25rem, 4vw, 2.5rem) 2rem;
  background: var(--brand-cream);
  overflow: hidden;
}

.hero-atmosphere {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(
      ellipse 70% 55% at 50% 18%,
      rgba(232, 93, 117, 0.1),
      transparent 60%
    ),
    radial-gradient(
      ellipse 50% 40% at 80% 80%,
      rgba(148, 163, 136, 0.08),
      transparent 55%
    ),
    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='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.035'/%3E%3C/svg%3E");
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  width: min(720px, 100%);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  justify-content: center;
  gap: 0;
}

.hero-brand {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 7vw, 3.75rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.02em;
  color: #1a1a1a;
}

.hero-slogan {
  margin: 0 0 1.15rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  max-width: 28rem;
}

.hero-slogan > span:first-child {
  font-family: var(--font-display);
  font-size: clamp(1.2rem, 3vw, 1.5rem);
  font-weight: 600;
  letter-spacing: 0.12em;
  line-height: 1.4;
  color: var(--logo-rose);
}

.hero-slogan-en {
  font-family: var(--font-body);
  font-size: clamp(0.88rem, 2vw, 0.98rem);
  font-weight: 400;
  font-style: italic;
  letter-spacing: 0.02em;
  color: var(--text-muted);
  line-height: 1.4;
}

.hero-claim {
  margin: 0 0 0.65rem;
  font-family: var(--font-body);
  font-size: clamp(1.05rem, 2.4vw, 1.25rem);
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.45;
}

.hero-support {
  margin: 0 0 1.75rem;
  max-width: 28rem;
  color: var(--text-secondary);
  font-size: 0.98rem;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
}

.hero-visual {
  flex: 1;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  width: 100%;
  min-height: 0;
}

.hero-logo {
  width: min(380px, 72vw);
  height: auto;
  object-fit: contain;
  opacity: 0;
  animation: logo-breathe 1.4s ease forwards 0.15s;
  filter: drop-shadow(0 18px 40px rgba(120, 80, 90, 0.12));
}

@keyframes logo-breathe {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.97);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* Pain */
.pain {
  background: var(--brand-bg);
  border-top: 1px solid var(--border-warm);
}

.pain-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.5rem;
  text-align: center;
}

.pain-list li {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 3vw, 1.65rem);
  font-weight: 500;
  line-height: 1.5;
  color: #222;
}

.pillars-words {
  margin: 3rem 0 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem 1rem;
  font-family: var(--font-display);
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  font-weight: 600;
  color: var(--brand-rose);
  letter-spacing: 0.08em;
}

.pillars-words span[aria-hidden="true"] {
  color: var(--brand-rose-soft);
}

/* Pillars */
.pillars {
  background: var(--brand-profile);
}

.pillar-poem {
  list-style: none;
  margin: 2.75rem 0 0;
  padding: 0;
  display: grid;
  gap: 1.75rem;
  max-width: 640px;
}

.pillar-poem li {
  display: grid;
  gap: 0.35rem;
  padding-bottom: 1.75rem;
  border-bottom: 1px solid var(--border-warm);
}

.pillar-poem li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.pillar-poem strong {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  color: #1a1a1a;
}

.pillar-poem span {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Feature loop */
.loop {
  background: var(--brand-bg);
  padding-left: 0;
  padding-right: 0;
}

.loop > .section-inner {
  padding-left: clamp(1.25rem, 4vw, 2.5rem);
  padding-right: clamp(1.25rem, 4vw, 2.5rem);
  margin-bottom: 2rem;
}

.feature-row {
  max-width: 1100px;
  margin: 0 auto;
  padding: clamp(2.5rem, 6vw, 4rem) clamp(1.25rem, 4vw, 2.5rem);
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  align-items: center;
}

@media (min-width: 860px) {
  .feature-row {
    grid-template-columns: 1fr 1fr;
    gap: 3.5rem;
  }

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

  .feature-row-reverse .phone {
    order: 1;
  }
}

.feature-copy h3 {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 1.9rem);
  font-weight: 600;
  line-height: 1.35;
}

.feature-copy p {
  margin: 0;
  color: var(--text-secondary);
  max-width: 28rem;
}

/* Phone mockups */
.phone {
  justify-self: center;
  width: min(280px, 78vw);
  border-radius: var(--radius-phone);
  padding: 10px;
  background: linear-gradient(160deg, #faf8f4, #ebe6de);
  box-shadow: var(--shadow-soft);
  border: 1px solid var(--border-warm);
}

.phone-screen {
  border-radius: calc(var(--radius-phone) - 8px);
  min-height: 460px;
  padding: 1.35rem 1.15rem;
  background: var(--card-wash);
  border: 1px solid #f0e9e4;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.mock-kicker {
  margin: 0;
  font-size: 0.78rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

.mock-pair {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
}

.mock-days {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.mock-days span {
  font-variant-numeric: tabular-nums;
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--brand-rose);
  line-height: 1;
  margin-right: 0.25rem;
}

.mock-status {
  display: grid;
  gap: 0.65rem;
  margin-top: 0.5rem;
}

.mock-status > div {
  background: var(--white);
  border: 1px solid var(--border-warm);
  border-radius: 14px;
  padding: 0.75rem 0.9rem;
  display: grid;
  gap: 0.2rem;
}

.mock-status span {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.mock-status strong {
  font-size: 0.95rem;
  font-weight: 600;
}

.mock-chip,
.mock-btn,
.mock-badge {
  margin-top: auto;
  text-align: center;
  border-radius: var(--radius-btn);
  padding: 0.75rem;
  font-size: 0.9rem;
  font-weight: 600;
}

.mock-chip,
.mock-btn {
  background: var(--brand-rose);
  color: #fff;
}

.mock-badge {
  background: var(--brand-rose-tint);
  color: var(--brand-rose);
  border: 1px solid #f5dfe4;
}

.mock-plan-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 600;
}

.mock-plan-meta {
  margin: 0;
  color: var(--text-secondary);
}

.mock-stat {
  margin: 0;
  color: var(--text-secondary);
}

.mock-stat strong {
  font-variant-numeric: tabular-nums;
  color: var(--brand-rose);
  font-size: 1.35rem;
}

.mock-memory {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  background: var(--white);
  border: 1px solid var(--border-warm);
  border-radius: 16px;
  padding: 0.85rem;
}

.mock-memory span {
  font-size: 1.35rem;
}

.mock-memory strong {
  display: block;
  font-size: 0.95rem;
}

.mock-memory small {
  color: var(--text-muted);
  font-size: 0.78rem;
}

.mock-map-canvas {
  position: relative;
  flex: 1;
  min-height: 200px;
  margin-top: 0.5rem;
  border-radius: 18px;
  background:
    radial-gradient(circle at 30% 40%, #fff0f2 0%, transparent 40%),
    linear-gradient(180deg, #f3f0ea, #ebe6dc);
  border: 1px solid var(--border-warm);
  overflow: hidden;
}

.mock-map-canvas .path-line {
  position: absolute;
  inset: 10% 5%;
  width: 90%;
  height: 80%;
}

.pin {
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--brand-rose);
  box-shadow: 0 0 0 4px rgba(232, 93, 117, 0.2);
}

.pin-a {
  left: 18%;
  top: 68%;
}

.pin-b {
  left: 52%;
  top: 38%;
}

.pin-c {
  left: 78%;
  top: 52%;
  background: var(--logo-sage);
  box-shadow: 0 0 0 4px rgba(148, 163, 136, 0.22);
}

/* Private */
.private {
  background: var(--brand-cream);
  border-top: 1px solid var(--border-warm);
  border-bottom: 1px solid var(--border-warm);
}

.private-pair {
  margin-top: 2.5rem;
  display: grid;
  gap: 1.5rem;
  text-align: left;
}

@media (min-width: 640px) {
  .private-pair {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

.private-pair > div {
  padding: 1.5rem 0;
  border-top: 1px solid var(--border-warm);
}

.private-pair h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
}

.private-pair p {
  margin: 0;
  color: var(--text-secondary);
}

/* Spark */
.spark {
  background: var(--brand-bg);
}

.spark-layout {
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

@media (min-width: 860px) {
  .spark-layout {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 3.5rem;
  }
}

.spark-copy .section-title,
.spark-copy h2 {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 4vw, 2.4rem);
  font-weight: 600;
}

.spark-copy p {
  margin: 0 0 1rem;
  color: var(--text-secondary);
}

.spark-note {
  font-size: 0.92rem !important;
  color: var(--text-muted) !important;
}

.mock-spark {
  background: linear-gradient(180deg, #faf9f6, #fff5f7);
}

.mock-bubble {
  align-self: flex-start;
  max-width: 92%;
  padding: 0.75rem 0.95rem;
  border-radius: 16px 16px 16px 6px;
  background: var(--white);
  border: 1px solid var(--border-warm);
  font-size: 0.88rem;
  color: var(--text-primary);
  line-height: 1.45;
}

.mock-input {
  margin-top: auto;
  border-radius: 14px;
  padding: 0.85rem 1rem;
  background: #fbf7f2;
  border: 1px solid var(--border-warm);
  color: var(--text-muted);
  font-size: 0.88rem;
}

/* Trust */
.trust {
  background: var(--brand-profile);
}

/* Waitlist */
.waitlist {
  background:
    radial-gradient(
      ellipse 80% 60% at 50% 0%,
      rgba(232, 93, 117, 0.08),
      transparent 55%
    ),
    var(--brand-cream);
}

.download-panel {
  margin: 2.25rem auto 0;
  display: grid;
  gap: 1.75rem;
  max-width: 520px;
  text-align: left;
}

.download-android,
.download-ios {
  padding: 1.5rem 0 0;
  border-top: 1px solid var(--border-warm);
}

.download-platform {
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: #1a1a1a;
}

.download-hint {
  margin: 0.85rem 0 0;
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--text-muted);
}

.download-ios-status {
  margin: 0 0 0.85rem;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.btn-download {
  min-width: 10.5rem;
}

.waitlist-form {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  justify-content: flex-start;
  max-width: 480px;
}

.waitlist-form input {
  flex: 1 1 220px;
  min-height: 48px;
  padding: 0 1rem;
  border-radius: var(--radius-btn);
  border: 1px solid var(--border-warm);
  background: var(--white);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--text-primary);
  outline: none;
  transition: border-color 0.2s ease;
}

.waitlist-form input:focus {
  border-color: var(--brand-rose-soft);
}

.waitlist-form .btn {
  flex: 0 0 auto;
}

.form-status {
  min-height: 1.25rem;
  margin: 0.65rem 0 0;
  font-size: 0.9rem;
  color: var(--logo-sage);
}

.download-ios .waitlist-form .btn-ghost {
  min-width: 6.5rem;
}

.form-status.is-error {
  color: #d64545;
}

.store-row {
  margin-top: 1.75rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  justify-content: center;
}

.store-pill {
  display: inline-flex;
  align-items: center;
  padding: 0.55rem 0.95rem;
  border-radius: 999px;
  border: 1px solid var(--border-warm);
  color: var(--text-secondary);
  font-size: 0.88rem;
  background: color-mix(in srgb, var(--white) 70%, transparent);
}

/* Footer */
.site-footer {
  padding: 2.5rem clamp(1.25rem, 4vw, 2.5rem) 3rem;
  background: var(--brand-bg);
  border-top: 1px solid var(--border-warm);
  text-align: center;
}

.footer-brand {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
}

.footer-slogan {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: 0.92rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--logo-rose);
}

.footer-privacy {
  margin: 0 0 1rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-meta {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-meta a:hover {
  color: var(--brand-rose);
}

.footer-beian {
  margin: 0.75rem 0 0;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.footer-beian a {
  color: var(--text-muted);
  text-decoration: none;
}

.footer-beian a:hover {
  color: var(--brand-rose);
}

/* Reveal on scroll */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .hero-logo {
    animation: none;
    opacity: 1;
  }

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

@media (max-width: 560px) {
  .site-nav {
    gap: 0.85rem;
    font-size: 0.85rem;
  }

  .hero {
    min-height: 100svh;
  }

  .phone-screen {
    min-height: 420px;
  }
}