:root { --ground: #f7f4f2; --surface: #fff; --ink: #2e2d29; --muted: #6d6660; --line: #e2dbd6; --accent: #8c1515; }
@media (prefers-color-scheme: dark) {
  :root { color-scheme: dark; --ground: #1a1817; --surface: #23201f; --ink: #ece6e2; --muted: #a79e97; --line: #3a3532; --accent: #e0676b; }
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; background: var(--ground); color: var(--ink); font: 16px/1.55 "Source Sans 3", "Segoe UI", system-ui, sans-serif; display: grid; place-items: center; padding: 16px; }
.card { width: 100%; max-width: 420px; background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 32px; }
.mark { margin: 0; font: 600 18px/1 "Source Serif 4", Georgia, serif; color: var(--accent); letter-spacing: .03em; }
h1 { font: 600 30px/1.15 "Source Serif 4", Georgia, serif; margin: 6px 0 12px; }
.lede { color: var(--muted); margin: 0 0 24px; }
.msg { min-height: 1.5em; color: var(--accent); font-size: 14px; margin: 16px 0 0; }
.fine { font-size: 13px; color: var(--muted); margin: 8px 0 0; }