:root {
  --bg: #262626;
  --card: rgba(0, 0, 0, 0.42);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.7);
  --border: rgba(255, 255, 255, 0.14);
  --shadow: rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family:
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    Helvetica,
    Arial,
    "Apple Color Emoji",
    "Segoe UI Emoji";
  color: var(--text);
  background: var(--bg) url("/assets/gray-background.png") center / cover no-repeat fixed;
  padding: max(18px, env(safe-area-inset-top)) max(18px, env(safe-area-inset-right))
    max(18px, env(safe-area-inset-bottom)) max(18px, env(safe-area-inset-left));
}

.card {
  width: min(720px, 100%);
  margin: 0 auto;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 18px 18px 12px;
  box-shadow: 0 18px 60px var(--shadow);
  backdrop-filter: blur(10px);
}

.header {
  display: flex;
  gap: 12px;
  align-items: center;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.mark {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: #2b2b2b;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

h1 {
  font-size: 22px;
  line-height: 1.15;
  margin: 0;
}

.sub {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.section {
  padding: 14px 2px 0;
}

h2 {
  font-size: 16px;
  margin: 0 0 8px;
}

p,
li {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

ol {
  margin: 8px 0 0;
  padding-left: 18px;
}

.actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin: 12px 0 0;
}

.button {
  display: inline-block;
  text-decoration: none;
  color: var(--text);
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.16);
  padding: 10px 12px;
  border-radius: 12px;
  font-size: 14px;
}

.button:active {
  transform: translateY(1px);
}

.button.secondary {
  background: rgba(0, 0, 0, 0.18);
}

.hint {
  margin-top: 10px;
  border-top: 1px solid var(--border);
  padding-top: 10px;
}

code {
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Monaco,
    Consolas,
    "Liberation Mono",
    "Courier New",
    monospace;
  font-size: 0.95em;
}

.footer {
  display: flex;
  gap: 8px;
  justify-content: center;
  align-items: center;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 13px;
}

.footer a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.footer a:hover {
  border-bottom-color: var(--muted);
}