:root {
  --bg: #ffffff;
  --fg: #111214;
  --muted: #5b6169;
  --accent: #0E7C6B;
  --accent-soft: #e6f2ef;
  --card: #f6f7f8;
  --border: #e5e7eb;
}
:root[data-theme="dark"] {
  --bg: #0B0C0F;
  --fg: #e8eaed;
  --muted: #9aa0a6;
  --accent: #2FA48F;
  --accent-soft: #12211e;
  --card: #15171b;
  --border: #262a2f;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0B0C0F;
    --fg: #e8eaed;
    --muted: #9aa0a6;
    --accent: #2FA48F;
    --accent-soft: #12211e;
    --card: #15171b;
    --border: #262a2f;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
  line-height: 1.65;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 820px;
  margin: 0 auto;
  padding: 18px 20px;
  border-bottom: 1px solid var(--border);
}
.brand { font-weight: 800; font-size: 20px; letter-spacing: .2px; color: var(--accent); }
.theme-toggle {
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--fg);
  border-radius: 10px;
  padding: 6px 10px;
  cursor: pointer;
  font-size: 15px;
}
.container { max-width: 820px; margin: 0 auto; padding: 28px 20px 8px; }
h1 { font-size: 28px; margin: 0 0 6px; }
h2 { font-size: 19px; margin: 30px 0 6px; }
p { margin: 10px 0; }
ul { padding-left: 22px; }
.muted { color: var(--muted); font-size: 14px; }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px 18px;
  margin: 18px 0;
}
label { display: block; font-weight: 600; margin: 12px 0 4px; }
input, textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg);
  color: var(--fg);
  font: inherit;
}
button.primary {
  background: var(--accent);
  color: #fff;
  border: 0;
  border-radius: 10px;
  padding: 11px 18px;
  font-weight: 700;
  cursor: pointer;
  margin-top: 14px;
}
button.primary:disabled { opacity: .6; cursor: default; }
.foot {
  max-width: 820px;
  margin: 30px auto 40px;
  padding: 18px 20px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}
.foot a { color: var(--accent); }
.ok { color: var(--accent); font-weight: 600; }
.err { color: #d93025; font-weight: 600; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .err { color: #ff6b5e; }
}