:root {
  color-scheme: light;
  --bg: #eef2f6;
  --sheet: #f8fafc;
  --ink: #17243d;
  --muted: #5a6880;
  --line: #c9d4e2;
  --grid: rgb(37 78 140 / 7%);
  --accent: #d99100;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0b1322;
    --sheet: #101b2e;
    --ink: #e4ebf6;
    --muted: #a5b3c9;
    --line: #2a3a56;
    --grid: rgb(140 180 240 / 6%);
    --accent: #f0b23a;
  }
}

* { box-sizing: border-box; }
html { min-height: 100%; }
body {
  min-height: 100vh;
  margin: 0;
  padding: max(24px, env(safe-area-inset-top, 0px))
           max(16px, env(safe-area-inset-right, 0px))
           max(24px, env(safe-area-inset-bottom, 0px))
           max(16px, env(safe-area-inset-left, 0px));
  display: grid;
  place-items: center;
  background: var(--bg);
  color: var(--ink);
  font-size: 16px;
  line-height: 1.6;
}

.sheet {
  position: relative;
  width: min(100%, 960px);
  padding: clamp(28px, 6vw, 72px);
  display: grid;
  gap: clamp(24px, 4vw, 40px);
  border: 1px solid var(--line);
  outline: 1px solid var(--line);
  outline-offset: 6px;
  background-color: var(--sheet);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px;
}

.sheet::before,
.sheet::after {
  position: absolute;
  width: 14px;
  height: 14px;
  border-color: var(--accent);
  border-style: solid;
  content: "";
}
.sheet::before { top: -1px; left: -1px; border-width: 2px 0 0 2px; }
.sheet::after { right: -1px; bottom: -1px; border-width: 0 2px 2px 0; }

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse 2.4s ease-in-out infinite;
}

.copy { display: grid; gap: 18px; max-width: 36rem; }
h1 {
  margin: 0;
  font-size: clamp(2.1rem, 6.4vw, 4.2rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -.015em;
  text-wrap: balance;
}
.th {
  margin: 0;
  font-size: clamp(1.25rem, 3.4vw, 1.9rem);
  font-weight: 600;
  line-height: 1.45;
  text-wrap: balance;
}
.sub { margin: 4px 0 0; color: var(--muted); }
.sub span { display: block; }

@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: .35; } }
@media (prefers-reduced-motion: reduce) { .dot { animation: none; } }