:root {
  --bg: #f4f7fa;
  --card: #fff;
  --text: #1c2733;
  --muted: #5d6b79;
  --border: #d5dde5;
  --accent: #0a6fb8;
  --accent-hover: #085a95;
  --ok-bg: #e5f5ea; --ok-text: #1d6b35;
  --err-bg: #fbe9e9; --err-text: #9b2323;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11171d; --card: #1a232c; --text: #e4eaf0; --muted: #98a6b3;
    --border: #2e3b47; --accent: #4ba3e3; --accent-hover: #6cb6ec;
    --ok-bg: #173323; --ok-text: #8fd9a8; --err-bg: #3a1c1c; --err-text: #f2a3a3;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
}
a { color: var(--accent); }

header.site {
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  padding: .75rem 1rem; background: var(--card); border-bottom: 1px solid var(--border);
}
.brand { font-weight: 700; text-decoration: none; color: var(--text); }
nav { display: flex; align-items: center; gap: 1rem; }
nav a { text-decoration: none; }

main { max-width: 26rem; margin: 2rem auto; padding: 0 1rem; }
h1 { font-size: 1.5rem; margin: 0 0 1rem; }
h2 { font-size: 1.1rem; margin: 0 0 .75rem; }

.card {
  background: var(--card); border: 1px solid var(--border); border-radius: 8px;
  padding: 1.25rem; margin-bottom: 1.25rem;
}
label { display: block; margin-bottom: 1rem; font-weight: 600; font-size: .95rem; }
input {
  display: block; width: 100%; margin-top: .3rem; padding: .55rem .65rem;
  font: inherit; font-weight: 400; color: var(--text); background: var(--bg);
  border: 1px solid var(--border); border-radius: 6px;
}
input:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
input:disabled { color: var(--muted); }
small { display: block; margin-top: .25rem; font-weight: 400; color: var(--muted); }

button {
  font: inherit; font-weight: 600; cursor: pointer;
  padding: .6rem 1.1rem; border: 0; border-radius: 6px;
  background: var(--accent); color: #fff;
}
button:hover { background: var(--accent-hover); }
button.link { background: none; color: var(--accent); padding: 0; font-weight: 400; }
button.link:hover { text-decoration: underline; background: none; }
form.inline { display: inline; margin: 0; }

.muted { color: var(--muted); font-size: .9rem; margin-bottom: 0; }
.flash { padding: .7rem .9rem; border-radius: 6px; margin: 0 0 1rem; }
ul.flash { padding-left: 2rem; }
.flash.ok { background: var(--ok-bg); color: var(--ok-text); }
.flash.error { background: var(--err-bg); color: var(--err-text); }