:root {
  color-scheme: light;
  --ink: #15211f;
  --muted: #586764;
  --paper: #f4f7f3;
  --panel: #ffffff;
  --accent: #216b5f;
  --line: #d9e2de;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: linear-gradient(145deg, #eef4f0 0%, var(--paper) 55%, #e8f0ed 100%);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

main {
  width: min(780px, calc(100% - 32px));
  margin: 48px auto;
  padding: clamp(28px, 6vw, 64px);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 24px 70px rgba(28, 61, 53, 0.10);
}

h1, h2 { line-height: 1.2; }
h1 { margin: 0.25rem 0 1rem; font-size: clamp(2.1rem, 7vw, 4rem); letter-spacing: -0.04em; }
h2 { margin-top: 2rem; font-size: 1.25rem; }
p, li { color: var(--muted); }
a { color: var(--accent); text-underline-offset: 0.16em; }

.eyebrow {
  margin: 0;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.lede { font-size: clamp(1.15rem, 3vw, 1.45rem); }
.updated { font-size: 0.92rem; }

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem 1.2rem;
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
}

.notice {
  padding: 1rem 1.25rem;
  background: #eef8f4;
  border: 1px solid #bcd9d0;
  border-radius: 12px;
}

.notice h2 { margin-top: 0; }

.handoff-form {
  display: grid;
  gap: 0.9rem;
  margin-top: 1.5rem;
}

.handoff-form label { font-weight: 700; }

input[type="file"] {
  width: 100%;
  padding: 0.8rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--paper);
}

button {
  width: 100%;
  padding: 0.9rem 1rem;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-weight: 750;
  cursor: pointer;
}

button:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.status {
  min-height: 1.65em;
  margin: 0;
  font-weight: 650;
}

.device-code {
  min-height: 2.2rem;
  margin: 0;
  color: var(--ink);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: clamp(1.35rem, 6vw, 2.25rem);
  font-weight: 800;
  letter-spacing: 0.08em;
  text-align: center;
}

code {
  overflow-wrap: anywhere;
}

@media (max-width: 520px) {
  main { margin: 16px auto; border-radius: 14px; }
}