:root {
  color-scheme: light;
  --ink: #1b1814;
  --muted: #6a6258;
  --paper: #f7f1e3;
  --paper-strong: #fff9eb;
  --line: #ded2bb;
  --accent: #d63f2f;
  --accent-dark: #8f261c;
  --blue: #245c86;
  --mint: #5f8c78;
  --shadow: 0 26px 70px rgba(40, 30, 20, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background:
    linear-gradient(90deg, rgba(27, 24, 20, 0.05) 1px, transparent 1px) 0 0 / 38px 38px,
    linear-gradient(rgba(27, 24, 20, 0.04) 1px, transparent 1px) 0 0 / 38px 38px,
    radial-gradient(circle at 80% 12%, rgba(214, 63, 47, 0.12), transparent 28rem),
    var(--paper);
  color: var(--ink);
  font-family: "Avenir Next", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
}

a {
  color: inherit;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -10rem;
  z-index: 10;
  padding: 0.75rem 1rem;
  background: var(--ink);
  color: var(--paper);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1rem clamp(1rem, 4vw, 4rem);
  border-bottom: 1px solid rgba(27, 24, 20, 0.14);
  background: rgba(247, 241, 227, 0.88);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 2.5rem;
  height: 2.5rem;
  place-items: center;
  border: 2px solid var(--ink);
  background: var(--accent);
  color: var(--paper-strong);
  font-weight: 900;
  box-shadow: 4px 4px 0 var(--ink);
}

.brand strong,
.brand small {
  display: block;
}

.brand strong {
  font-size: 1rem;
  line-height: 1.1;
}

.brand small {
  color: var(--muted);
  font-size: 0.76rem;
}

.nav-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.5rem;
}

.nav-links a {
  padding: 0.45rem 0.7rem;
  border: 1px solid transparent;
  color: var(--muted);
  font-size: 0.9rem;
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  border-color: var(--ink);
  color: var(--ink);
  outline: none;
}

main {
  overflow: hidden;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(18rem, 0.85fr);
  gap: clamp(2rem, 6vw, 5rem);
  align-items: center;
  min-height: calc(100vh - 4.5rem);
  padding: clamp(3rem, 7vw, 7rem) clamp(1rem, 5vw, 5rem) clamp(4rem, 8vw, 6rem);
}

.hero-copy {
  max-width: 58rem;
}

.eyebrow {
  margin: 0 0 0.85rem;
  color: var(--accent-dark);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 14ch;
  margin-bottom: 1.2rem;
  font-family: Georgia, "Songti SC", serif;
  font-size: clamp(3.2rem, 9vw, 8.2rem);
  line-height: 0.92;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0.85rem;
  font-family: Georgia, "Songti SC", serif;
  font-size: clamp(2rem, 5vw, 4.6rem);
  line-height: 1;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 0.75rem;
  font-size: 1.35rem;
  line-height: 1.25;
}

.hero-text {
  max-width: 46rem;
  color: var(--muted);
  font-size: clamp(1.02rem, 1.6vw, 1.22rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3rem;
  padding: 0.78rem 1.1rem;
  border: 2px solid var(--ink);
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translate(-2px, -2px);
  outline: none;
}

.button.primary {
  background: var(--accent);
  color: var(--paper-strong);
  box-shadow: 6px 6px 0 var(--ink);
}

.button.secondary {
  background: var(--paper-strong);
  box-shadow: 6px 6px 0 rgba(36, 92, 134, 0.9);
}

.signal-panel {
  position: relative;
  display: grid;
  gap: 1rem;
}

.signal-panel::before {
  content: "";
  position: absolute;
  inset: -1.75rem 2rem auto auto;
  width: 10rem;
  height: 10rem;
  border: 2px solid var(--ink);
  background:
    linear-gradient(135deg, transparent 45%, rgba(27, 24, 20, 0.25) 46%, rgba(27, 24, 20, 0.25) 52%, transparent 53%),
    var(--mint);
  transform: rotate(8deg);
}

.wallpaper-card {
  position: relative;
  z-index: 1;
  min-height: 25rem;
  padding: clamp(1.4rem, 3vw, 2rem);
  border: 2px solid var(--ink);
  background:
    linear-gradient(135deg, rgba(255, 249, 235, 0.88), rgba(255, 249, 235, 0.55)),
    repeating-linear-gradient(90deg, rgba(27, 24, 20, 0.08) 0 1px, transparent 1px 14px),
    linear-gradient(160deg, #f6c447, #e56f43 46%, #245c86 47%, #132f48);
  box-shadow: var(--shadow);
}

.wallpaper-card::after {
  content: "";
  position: absolute;
  right: 1.2rem;
  bottom: 1.2rem;
  width: 42%;
  aspect-ratio: 9 / 16;
  border: 2px solid var(--ink);
  background:
    radial-gradient(circle at 50% 12%, rgba(255, 255, 255, 0.82) 0 0.25rem, transparent 0.32rem),
    linear-gradient(180deg, rgba(255, 255, 255, 0.2), transparent),
    linear-gradient(145deg, #0f2031, #245c86 48%, #e56f43 49%, #f6c447);
  box-shadow: 8px 8px 0 rgba(27, 24, 20, 0.8);
}

.card-label {
  display: inline-block;
  margin-bottom: 8rem;
  padding: 0.28rem 0.55rem;
  background: var(--ink);
  color: var(--paper-strong);
  font-size: 0.72rem;
  font-weight: 800;
}

.wallpaper-card strong {
  display: block;
  max-width: 10rem;
  font-family: Georgia, "Songti SC", serif;
  font-size: 2.2rem;
  line-height: 1.02;
}

.wallpaper-card p {
  position: relative;
  z-index: 1;
  max-width: 13rem;
  margin: 1rem 0 0;
  color: var(--ink);
  font-weight: 700;
}

.metrics-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
}

.metrics-grid div {
  min-height: 7rem;
  padding: 0.8rem;
  border: 2px solid var(--ink);
  background: var(--paper-strong);
  box-shadow: 4px 4px 0 rgba(27, 24, 20, 0.18);
}

.metrics-grid span,
.metrics-grid small {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
}

.metrics-grid strong {
  display: block;
  margin: 0.35rem 0;
  font-family: Georgia, "Songti SC", serif;
  font-size: 2.2rem;
  line-height: 1;
}

.section {
  padding: clamp(3rem, 7vw, 6rem) clamp(1rem, 5vw, 5rem);
}

.intro-band {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(1.5rem, 5vw, 4rem);
  align-items: start;
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
}

.intro-band .eyebrow,
.intro-band p {
  color: #f1d3a2;
}

.intro-band h2 {
  color: var(--paper-strong);
}

.intro-band > p {
  margin-bottom: 0;
  font-size: clamp(1rem, 1.6vw, 1.2rem);
}

.section-heading {
  max-width: 44rem;
  margin-bottom: clamp(1.5rem, 4vw, 3rem);
}

.section-heading p:not(.eyebrow) {
  color: var(--muted);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.feature-card {
  display: flex;
  flex-direction: column;
  min-height: 20rem;
  padding: 1.35rem;
  border: 2px solid var(--ink);
  background: var(--paper-strong);
  box-shadow: 6px 6px 0 rgba(27, 24, 20, 0.14);
}

.feature-number {
  margin-bottom: 2rem;
  color: var(--blue);
  font-family: Georgia, "Songti SC", serif;
  font-size: 3rem;
  line-height: 1;
}

.feature-card p {
  color: var(--muted);
}

.feature-card a {
  margin-top: auto;
  color: var(--accent-dark);
  font-weight: 800;
  text-decoration-thickness: 2px;
  text-underline-offset: 0.18em;
}

.start-section {
  display: grid;
  grid-template-columns: minmax(0, 0.7fr) minmax(0, 1.3fr);
  gap: clamp(1.5rem, 5vw, 4rem);
  align-items: start;
  background: #efe2ca;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.steps article {
  min-height: 17rem;
  padding: 1.25rem;
  border: 2px solid var(--ink);
  background: var(--paper-strong);
  box-shadow: 6px 6px 0 rgba(27, 24, 20, 0.14);
}

.steps span {
  display: grid;
  width: 2.25rem;
  height: 2.25rem;
  margin-bottom: 2rem;
  place-items: center;
  border: 2px solid var(--ink);
  background: var(--blue);
  color: var(--paper-strong);
  font-weight: 800;
  box-shadow: 4px 4px 0 var(--ink);
}

.steps p {
  margin-bottom: 0;
  color: var(--muted);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.5rem clamp(1rem, 5vw, 5rem);
  border-top: 1px solid rgba(27, 24, 20, 0.16);
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: var(--ink);
  font-weight: 800;
}

@media (max-width: 920px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav-links {
    justify-content: flex-start;
  }

  .hero,
  .intro-band,
  .start-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  h1 {
    max-width: 11ch;
  }

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

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

  .feature-card {
    min-height: 15rem;
  }

  .steps article {
    min-height: 13rem;
  }

  .site-footer {
    flex-direction: column;
  }
}

@media (max-width: 560px) {
  .site-header {
    position: static;
  }

  .nav-links a {
    padding-inline: 0.3rem;
  }

  h1 {
    font-size: 3rem;
  }

  .hero-actions,
  .button {
    width: 100%;
  }

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

  .wallpaper-card {
    min-height: 22rem;
  }

  .card-label {
    margin-bottom: 5rem;
  }
}