:root {
  --paper: #fffaf0;
  --ink: #17211c;
  --muted: #68736a;
  --line: rgba(23, 33, 28, 0.12);
  --green: #0f9f73;
  --green-dark: #0b3328;
  --blue: #3978f2;
  --orange: #f29a35;
  --pink: #e85d87;
  --shadow: 0 28px 80px rgba(42, 52, 39, 0.16);
  color-scheme: light;
  font-family: "Avenir Next", "Hiragino Sans", "Yu Gothic", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 14% 10%, rgba(57, 120, 242, 0.15), transparent 32rem),
    radial-gradient(circle at 86% 12%, rgba(15, 159, 115, 0.18), transparent 34rem),
    linear-gradient(135deg, #eef4ec 0%, #fff8e8 54%, #ecefe5 100%);
  overflow-x: hidden;
}

.page {
  width: min(1220px, calc(100% - 48px));
  margin: 0 auto;
  padding: 38px 0;
}

.page > *,
.demo-shell,
.stage,
.parent-frame,
.switcher,
.plan-card,
.takeaway {
  min-width: 0;
  max-width: 100%;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  color: var(--green);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0.14em;
}

.eyebrow::before {
  width: 10px;
  height: 10px;
  border-radius: 999px;
  background: currentColor;
  box-shadow: 2px 2px 0 var(--orange);
  content: "";
}

h1,
h2,
p,
pre {
  margin: 0;
}

h1 {
  font-size: clamp(32px, 5vw, 60px);
  line-height: 1.2;
}

.lead {
  margin-top: 18px;
  color: var(--muted);
  font-size: clamp(16px, 1.7vw, 18px);
  font-weight: 700;
  line-height: 1.75;
  overflow-wrap: anywhere;
}

.lead,
.plan-card p,
.takeaway p {
  word-break: auto-phrase;
}

.demo-shell {
  margin-top: 28px;
  border: 1px solid var(--line);
  border-radius: 34px;
  background: rgba(255, 250, 240, 0.78);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.demo-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 20px 22px;
  border-bottom: 1px solid var(--line);
}

.demo-head span,
.frame-label span {
  color: var(--green);
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.demo-head strong {
  display: block;
  margin-top: 4px;
  font-size: 20px;
  letter-spacing: -0.04em;
}

.width-control {
  display: grid;
  gap: 8px;
  min-width: 260px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.62);
}

.width-control input {
  accent-color: var(--green);
}

.stage {
  --parent-width: 920px;
  display: grid;
  gap: 18px;
  padding: 24px;
  background:
    linear-gradient(rgba(23, 33, 28, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 33, 28, 0.055) 1px, transparent 1px),
    var(--paper);
  background-size: 34px 34px;
}

.parent-frame {
  width: min(var(--parent-width), 100%);
  margin-inline: auto;
  padding: 18px;
  border: 1px dashed rgba(23, 33, 28, 0.22);
  border-radius: 28px;
  background: rgba(255, 250, 240, 0.72);
  transition: width 180ms ease;
}

.frame-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.frame-label strong {
  color: var(--muted);
  font-size: 13px;
  font-weight: 900;
}

.switcher {
  --threshold: 720px;
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.switcher > * {
  flex-grow: 1;
  flex-basis: calc((var(--threshold) - 100%) * 999);
}

.plan-card {
  display: grid;
  align-content: start;
  min-height: 220px;
  padding: 22px;
  border-radius: 26px;
  color: #fff;
  background:
    radial-gradient(circle at 84% 18%, rgba(255, 255, 255, 0.16), transparent 9rem),
    linear-gradient(135deg, #0b3328, var(--green));
  box-shadow: 0 18px 48px rgba(15, 159, 115, 0.18);
}

.plan-card:nth-child(2) {
  background:
    radial-gradient(circle at 84% 18%, rgba(255, 255, 255, 0.16), transparent 9rem),
    linear-gradient(135deg, #173fe0, var(--blue));
  box-shadow: 0 18px 48px rgba(57, 120, 242, 0.18);
}

.plan-card:nth-child(3) {
  background:
    radial-gradient(circle at 84% 18%, rgba(255, 255, 255, 0.16), transparent 9rem),
    linear-gradient(135deg, #b73c74, var(--pink));
  box-shadow: 0 18px 48px rgba(232, 93, 135, 0.18);
}

.plan-card span {
  display: inline-flex;
  width: fit-content;
  margin-bottom: 42px;
  padding: 8px 11px;
  border-radius: 999px;
  color: var(--green-dark);
  background: rgba(255, 255, 255, 0.86);
  font-size: 13px;
  font-weight: 900;
}

.plan-card h2 {
  font-size: 34px;
  line-height: 1.04;
  letter-spacing: -0.055em;
}

.plan-card p {
  margin-top: 12px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 14px;
  font-weight: 800;
  line-height: 1.75;
}

.code-panel pre {
  padding: 18px;
  border-radius: 22px;
  color: #ecfff4;
  background: var(--green-dark);
  overflow: auto;
}

.code-panel code {
  font: 800 13px/1.65 "SFMono-Regular", Consolas, monospace;
}

.takeaway {
  display: flex;
  gap: 14px;
  align-items: center;
  margin-top: 22px;
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: rgba(255, 250, 240, 0.82);
  box-shadow: var(--shadow);
}

.takeaway span {
  flex: 0 0 auto;
  padding: 8px 12px;
  border-radius: 999px;
  color: #fff;
  background: var(--green-dark);
  font-size: 12px;
  font-weight: 900;
}

.takeaway p {
  color: var(--muted);
  font-size: 14px;
  font-weight: 900;
  line-height: 1.7;
}

@media (max-width: 900px) {
  .page {
    width: min(100% - 28px, 720px);
    padding: 28px 0;
  }

  .demo-head,
  .takeaway {
    align-items: flex-start;
    flex-direction: column;
  }

  .width-control {
    width: 100%;
    min-width: 0;
  }
}

@media (max-width: 560px) {
  .page {
    width: calc(100vw - 32px);
    max-width: 350px;
    margin-right: auto;
    margin-left: 16px;
  }

  h1 {
    font-size: clamp(32px, 8.5vw, 38px);
  }

  .stage {
    padding-inline: 14px;
  }

  .parent-frame {
    padding: 14px;
  }

  .frame-label {
    align-items: flex-start;
    flex-direction: column;
  }

  .plan-card {
    min-height: 190px;
    padding: 20px;
  }
}