:root {
  color-scheme: light;
  --navy-950: #071b36;
  --navy-900: #0b2c5f;
  --navy-800: #123e7a;
  --blue-700: #1266d5;
  --blue-600: #1b76ea;
  --blue-100: #dbeaff;
  --blue-50: #edf5ff;
  --surface: #ffffff;
  --background: #f3f7fc;
  --text: #152238;
  --text-muted: #5b6b80;
  --line: #dce6f2;
  --success: #18864b;
  --shadow: 0 14px 40px rgba(15, 53, 98, 0.08);
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 12px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--background);
  color: var(--text);
  font-family:
    "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, -apple-system,
    BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

button,
input,
textarea {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

.section-shell {
  width: min(100% - 32px, 1040px);
  margin-inline: auto;
}

.hero {
  padding-top: 20px;
}

.hero-card {
  position: relative;
  overflow: hidden;
  padding: 36px 24px 30px;
  border: 1px solid #d5e4f7;
  border-top: 4px solid var(--blue-600);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.hero-card::after {
  position: absolute;
  right: -34px;
  top: -44px;
  width: 136px;
  height: 136px;
  border: 24px solid var(--blue-50);
  border-radius: 50%;
  content: "";
  pointer-events: none;
}

.success-icon {
  position: relative;
  z-index: 1;
  display: grid;
  width: 72px;
  height: 72px;
  margin-bottom: 22px;
  place-items: center;
  border-radius: 50%;
  background: #e7f7ee;
}

.success-icon svg {
  width: 48px;
  height: 48px;
  overflow: visible;
}

.success-icon circle {
  fill: none;
  stroke: var(--success);
  stroke-width: 2.5;
}

.success-icon path {
  fill: none;
  stroke: var(--success);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 3.5;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.eyebrow,
.section-kicker {
  margin: 0 0 8px;
  color: var(--blue-700);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1,
h2,
h3 {
  margin-top: 0;
  color: var(--navy-950);
  line-height: 1.35;
}

h1 {
  margin-bottom: 15px;
  font-size: clamp(28px, 8vw, 42px);
  letter-spacing: -0.04em;
}

h2 {
  margin-bottom: 10px;
  font-size: clamp(24px, 6vw, 32px);
  letter-spacing: -0.025em;
}

h3 {
  margin-bottom: 10px;
  font-size: 19px;
}

.hero-lead {
  margin: 0 0 8px;
  color: var(--navy-900);
  font-size: 18px;
  font-weight: 700;
}

.hero-copy {
  max-width: 760px;
  margin: 0;
  color: var(--text-muted);
}

.status-tag {
  display: inline-flex;
  align-items: center;
  margin: 22px 0 0;
  padding: 9px 13px;
  border: 1px solid #cfe1f8;
  border-radius: 999px;
  background: var(--blue-50);
  color: var(--navy-800);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.5;
}

.status-dot {
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--blue-600);
  box-shadow: 0 0 0 4px rgba(27, 118, 234, 0.12);
}

.content-section {
  padding-top: 56px;
}

.section-heading {
  margin-bottom: 24px;
}

.section-heading > p:last-child,
.prepare-copy > p:last-child {
  max-width: 650px;
  margin: 0;
  color: var(--text-muted);
}

.step-list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.step-card {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  padding: 22px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(20, 56, 100, 0.05);
}

.step-number {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border-radius: 14px;
  background: var(--navy-900);
  color: #ffffff;
  font-size: 14px;
  font-weight: 800;
}

.step-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 15px;
}

.prepare-card {
  padding: 28px 22px 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.check-list {
  display: grid;
  gap: 11px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding: 12px 14px 12px 46px;
  border: 1px solid #e1eaf4;
  border-radius: var(--radius-sm);
  background: #f9fbfe;
  color: var(--navy-950);
  font-weight: 600;
}

.check-list li::before {
  position: absolute;
  left: 15px;
  top: 50%;
  display: grid;
  width: 20px;
  height: 20px;
  transform: translateY(-50%);
  place-items: center;
  border-radius: 50%;
  background: #e0efff;
  color: var(--blue-700);
  content: "✓";
  font-size: 13px;
  font-weight: 900;
}

.prepare-note {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 18px 0 0;
  padding: 13px 14px;
  border-radius: var(--radius-sm);
  background: var(--blue-50);
  color: var(--navy-800);
  font-size: 14px;
}

.prepare-note span {
  display: grid;
  flex: 0 0 auto;
  width: 21px;
  height: 21px;
  margin-top: 2px;
  place-items: center;
  border-radius: 50%;
  background: var(--blue-700);
  color: #ffffff;
  font-family: Georgia, serif;
  font-size: 13px;
  font-weight: 700;
  line-height: 1;
}

.wechat-card {
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: var(--navy-900);
  box-shadow: 0 18px 50px rgba(10, 42, 91, 0.18);
}

.wechat-intro {
  padding: 30px 22px 28px;
  color: #dceaff;
}

.section-kicker-light {
  color: #8fc5ff;
}

.wechat-intro h2 {
  color: #ffffff;
}

.wechat-intro > p:not(.section-kicker, .copy-feedback) {
  margin: 0;
  color: #c8daf3;
}

.message-format {
  margin: 22px 0 18px;
  padding: 16px;
  border: 1px solid rgba(152, 200, 255, 0.25);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.07);
}

.message-format span,
.message-format small {
  display: block;
}

.message-format span {
  color: #ffffff;
  font-size: 18px;
  font-weight: 800;
}

.message-format small {
  margin-top: 4px;
  color: #a9c5e7;
  font-size: 13px;
}

.copy-button {
  display: inline-flex;
  min-height: 50px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  width: 100%;
  padding: 12px 18px;
  border: 0;
  border-radius: 12px;
  background: var(--blue-600);
  color: #ffffff;
  cursor: pointer;
  font-weight: 800;
  transition:
    background-color 160ms ease,
    transform 160ms ease;
}

.copy-button:hover {
  background: #3187eb;
}

.copy-button:active {
  transform: translateY(1px);
}

.copy-button:focus-visible {
  outline: 3px solid rgba(155, 207, 255, 0.65);
  outline-offset: 3px;
}

.copy-button svg {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.copy-feedback {
  min-height: 26px;
  margin: 10px 0 0;
  color: #a8ffd0;
  font-size: 14px;
  font-weight: 700;
}

.copy-feedback.is-error {
  color: #ffd1d1;
}

.qr-panel {
  display: grid;
  padding: 28px 22px 30px;
  place-items: center;
  background: #f6f9fd;
}

.qr-frame {
  display: grid;
  position: relative;
  overflow: hidden;
  width: min(100%, 260px);
  min-width: 220px;
  aspect-ratio: 1;
  padding: 10px;
  place-items: center;
  border: 1px solid #d7e2ef;
  border-radius: 18px;
  background: #ffffff;
  box-shadow: 0 10px 28px rgba(15, 47, 84, 0.1);
}

.qr-frame img {
  display: block;
  width: 100%;
  height: 100%;
  border-radius: 10px;
  object-fit: contain;
}

.qr-error {
  position: absolute;
  inset: 10px;
  display: grid;
  min-height: 0;
  width: auto;
  height: auto;
  padding: 20px;
  place-content: center;
  border: 2px dashed #b6c7db;
  border-radius: 10px;
  color: var(--text-muted);
  text-align: center;
}

.qr-error[hidden] {
  display: none;
}

.qr-error strong,
.qr-error span {
  display: block;
}

.qr-error strong {
  margin-bottom: 8px;
  color: var(--navy-900);
}

.qr-error span {
  font-size: 13px;
  line-height: 1.55;
}

.qr-tip {
  max-width: 310px;
  margin: 16px 0 0;
  color: var(--text-muted);
  font-size: 13px;
  text-align: center;
}

.about-card {
  padding: 28px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.identity-list {
  display: grid;
  gap: 10px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.identity-list li {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 0;
  border-bottom: 1px solid #e7edf5;
  color: var(--navy-950);
  font-weight: 650;
}

.identity-list li:last-child {
  border-bottom: 0;
}

.identity-icon {
  display: grid;
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 10px;
  background: var(--blue-50);
  color: var(--blue-700);
  font-size: 12px;
  font-weight: 800;
}

.site-footer {
  margin-top: 56px;
  padding: 36px 0 40px;
  background: var(--navy-950);
  color: #aebfd4;
}

.footer-note {
  font-size: 13px;
}

.footer-note p {
  margin: 0;
}

.site-footer blockquote {
  margin: 26px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  color: #ffffff;
  font-size: clamp(18px, 5vw, 23px);
  font-weight: 700;
  line-height: 1.55;
}

.toast {
  position: fixed;
  z-index: 10;
  left: 50%;
  bottom: calc(24px + env(safe-area-inset-bottom));
  max-width: calc(100% - 32px);
  padding: 11px 16px;
  transform: translate(-50%, 20px);
  border-radius: 10px;
  background: #0f2f59;
  box-shadow: 0 10px 30px rgba(7, 28, 57, 0.25);
  color: #ffffff;
  font-size: 14px;
  font-weight: 700;
  opacity: 0;
  pointer-events: none;
  transition:
    opacity 180ms ease,
    transform 180ms ease;
}

.toast.is-visible {
  transform: translate(-50%, 0);
  opacity: 1;
}

@media (min-width: 720px) {
  .section-shell {
    width: min(100% - 64px, 1040px);
  }

  .hero {
    padding-top: 36px;
  }

  .hero-card {
    display: grid;
    grid-template-columns: 90px 1fr;
    gap: 28px;
    padding: 48px;
  }

  .success-icon {
    margin-bottom: 0;
  }

  .content-section {
    padding-top: 76px;
  }

  .step-list {
    grid-template-columns: repeat(3, 1fr);
  }

  .step-card {
    grid-template-columns: 1fr;
    align-content: start;
    padding: 26px 24px;
  }

  .prepare-card,
  .about-card {
    padding: 38px 40px;
  }

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

  .wechat-card {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(300px, 0.85fr);
  }

  .wechat-intro {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 46px 44px;
  }

  .copy-button {
    width: auto;
    align-self: flex-start;
    min-width: 190px;
  }

  .qr-panel {
    padding: 40px 32px;
  }

  .about-card {
    display: grid;
    grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
    gap: 54px;
    align-items: center;
  }

  .identity-list {
    margin-top: 0;
  }

  .site-footer {
    margin-top: 76px;
    padding-block: 44px;
  }

  .site-footer .section-shell {
    display: grid;
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    gap: 64px;
    align-items: center;
  }

  .site-footer blockquote {
    margin: 0;
    padding: 0 0 0 28px;
    border-top: 0;
    border-left: 1px solid rgba(255, 255, 255, 0.14);
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}