:root {
  --paper: #f4efe4;
  --paper-2: #ebe3d2;
  --card: #fbf8f1;
  --ink: #1f2a24;
  --ink-2: #5e6b62;
  --seal: #b8432f;
  --seal-dark: #95321f;
  --ochre: #a07a3c;
  --line: #d6cbb4;
  --ok: #3d6b4f;
  --serif: "Source Han Serif SC", "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --mono: "JetBrains Mono", "Cascadia Mono", Consolas, "Courier New", monospace;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  font-family: var(--sans);
  color: var(--ink);
  line-height: 1.6;
  min-height: 100vh;
  background-color: var(--paper);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(184, 67, 47, 0.07), transparent 38%),
    radial-gradient(circle at 92% 96%, rgba(160, 122, 60, 0.1), transparent 42%),
    repeating-linear-gradient(0deg, transparent 0 31px, rgba(160, 122, 60, 0.09) 31px 32px);
}
h1, h2, h3 { font-family: var(--serif); font-weight: 700; letter-spacing: 0.04em; margin: 0; }
.mono { font-family: var(--mono); letter-spacing: 0.02em; }
.muted { color: var(--ink-2); }
.icon { width: 1.1em; height: 1.1em; flex: none; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

label { display: block; font-size: 0.92rem; font-weight: 600; margin-bottom: 6px; }
input[type="text"], input[type="password"], input[type="search"], select {
  width: 100%;
  font: inherit;
  font-size: 1.05rem;
  color: var(--ink);
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: 2px;
  padding: 11px 13px;
  transition: border-color 0.15s, box-shadow 0.15s;
}
input:focus, select:focus { outline: none; border-color: var(--ink); box-shadow: 0 0 0 3px rgba(31, 42, 36, 0.12); }
input[aria-invalid="true"] { border-color: var(--seal); }
.hint { font-size: 0.85rem; color: var(--ink-2); margin-top: 4px; }
.field-error { font-size: 0.85rem; color: var(--seal); margin-top: 4px; min-height: 1.2em; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font: inherit;
  font-weight: 600;
  font-size: 1rem;
  padding: 11px 20px;
  border-radius: 2px;
  border: 1.5px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.12s, background 0.15s, color 0.15s;
}
.btn:hover { background: #2d3b33; }
.btn:active { transform: translateY(1px); }
.btn:focus-visible, a:focus-visible, button:focus-visible { outline: 3px solid var(--ochre); outline-offset: 2px; }
.btn.seal { background: var(--seal); border-color: var(--seal); color: #fff; }
.btn.seal:hover { background: var(--seal-dark); border-color: var(--seal-dark); }
.btn.ghost { background: transparent; color: var(--ink); }
.btn.ghost:hover { background: var(--paper-2); }
.btn.small { padding: 6px 12px; font-size: 0.88rem; }
.btn[disabled] { opacity: 0.45; cursor: not-allowed; transform: none; }
.btn .spin { width: 1em; height: 1em; border: 2px solid currentColor; border-right-color: transparent; border-radius: 50%; animation: spin 0.7s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

.alert { padding: 12px 14px; border-left: 4px solid var(--seal); background: rgba(184, 67, 47, 0.08); color: var(--seal-dark); font-weight: 600; }
.alert.ok { border-color: var(--ok); background: rgba(61, 107, 79, 0.08); color: var(--ok); }
.alert:empty { display: none; }

.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); border: 0; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }