:root {
  color-scheme: light;
  --bg: #f6f8fb;
  --panel: #ffffff;
  --text: #1f2937;
  --muted: #667085;
  --line: #e4e7ec;
  --primary: #2563eb;
  --primary-soft: rgba(37, 99, 235, 0.1);
  --shadow: 0 12px 28px rgba(31, 41, 55, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  background: var(--bg);
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
}

.page {
  width: min(960px, calc(100% - 32px));
  margin: 0 auto;
  padding: 48px 0;
}

.page-header {
  margin-bottom: 28px;
  text-align: center;
}

.page-header h1 {
  margin: 0;
  font-size: 40px;
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: 0;
}

.page-header p {
  max-width: 560px;
  margin: 12px auto 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
}

.cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.card {
  display: flex;
  min-height: 232px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 26px 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  box-shadow: 0 4px 14px rgba(31, 41, 55, 0.05);
  text-align: center;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.card:hover,
.card:focus-visible {
  transform: translateY(-3px);
  border-color: rgba(37, 99, 235, 0.36);
  box-shadow: var(--shadow);
  text-decoration: none;
  outline: none;
}

.card img {
  width: 82px;
  height: 82px;
  object-fit: contain;
}

.card h2 {
  margin: 18px 0 8px;
  font-size: 22px;
  line-height: 1.25;
  font-weight: 700;
  letter-spacing: 0;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.card span {
  margin-top: 18px;
  color: var(--primary);
  font-size: 14px;
  font-weight: 700;
}

.page-shell {
  width: min(980px, calc(100% - 32px));
  margin: 0 auto;
  padding: 44px 0 56px;
}

.guide-hero {
  margin-bottom: 24px;
  text-align: center;
}

.guide-hero h2 {
  margin: 0;
  font-size: 38px;
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: 0;
}

.steps {
  display: grid;
  gap: 18px;
}

.step-card,
.note-card {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.step-copy,
.note-card {
  padding: 24px 26px;
}

.step-copy h4 {
  margin: 0;
  font-size: 18px;
  line-height: 1.75;
  font-weight: 600;
  overflow-wrap: anywhere;
}

.download-link {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  margin: 0 4px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary);
  font-size: 15px;
  font-weight: 700;
  white-space: nowrap;
}

.figure-wrap {
  display: grid;
  gap: 18px;
  padding: 0 26px 26px;
}

figure {
  margin: 0;
}

.tutorial-img {
  display: block;
  width: min(100%, 760px);
  height: auto;
  margin: 0 auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 8px 22px rgba(31, 41, 55, 0.08);
}

.image-wide .tutorial-img {
  width: min(100%, 900px);
}

.image-phone .tutorial-img {
  width: min(100%, 680px);
}

figcaption {
  margin-top: 12px;
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

.note-card {
  color: var(--text);
  font-size: 16px;
  line-height: 1.8;
}

@media (max-width: 640px) {
  .page {
    width: min(100% - 24px, 960px);
    padding: 32px 0;
  }

  .page-header {
    text-align: left;
  }

  .page-header h1 {
    font-size: 32px;
  }

  .page-header p {
    margin-left: 0;
    margin-right: 0;
    font-size: 16px;
  }

  .cards {
    grid-template-columns: 1fr;
  }

  .card {
    min-height: 210px;
  }

  .page-shell {
    width: min(100% - 24px, 980px);
    padding: 32px 0 42px;
  }

  .guide-hero {
    text-align: left;
  }

  .guide-hero h2 {
    font-size: 30px;
  }

  .step-copy,
  .note-card {
    padding: 20px 18px;
  }

  .step-copy h4 {
    font-size: 16px;
    line-height: 1.7;
    word-break: break-word;
  }

  .download-link {
    display: flex;
    width: fit-content;
    min-height: 30px;
    margin: 8px 4px 6px 0;
    padding: 0 10px;
    font-size: 14px;
  }

  .figure-wrap {
    gap: 16px;
    padding: 0 18px 20px;
  }

  .tutorial-img {
    max-width: 100%;
  }
}