:root {
  --paper: #f5f1ea;
  --card: #fffcf7;
  --ink: #2b2118;
  --muted: #75695d;
  --line: #d9d0c1;
  --rust: #a93e2f;
  --soft-rust: #f1ded5;
  --display: "Songti SC", STSong, SimSun, serif;
  --text: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Menlo, monospace;
}

* { box-sizing: border-box; }
html { min-width: 320px; background: var(--paper); color-scheme: light; }
body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  background:
    linear-gradient(135deg, transparent 0 49.8%, rgba(169, 62, 47, .06) 50% 50.15%, transparent 50.3%),
    radial-gradient(circle at 76% 8%, rgba(169, 62, 47, .1), transparent 30%),
    var(--paper);
  color: var(--ink);
  font-family: var(--text);
  -webkit-font-smoothing: antialiased;
}

.login-shell { display: grid; min-height: 100vh; place-items: center; padding: 28px; }
.login-card {
  width: min(100%, 490px);
  padding: clamp(30px, 7vw, 62px);
  border: 1px solid var(--line);
  border-top: 5px solid var(--rust);
  background: rgba(255, 252, 247, .94);
  box-shadow: 0 4px 0 rgba(43, 33, 24, .04), 0 26px 70px rgba(43, 33, 24, .1);
}
.login-kicker { display: flex; align-items: center; gap: 9px; color: var(--rust); font: 600 11px/1 var(--mono); letter-spacing: .15em; }
.signal-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--rust); box-shadow: 0 0 0 5px var(--soft-rust); }
.login-heading { display: flex; align-items: center; gap: 20px; margin-top: 38px; }
.login-mark { display: grid; width: 58px; height: 58px; place-content: center; border: 1px solid var(--rust); color: var(--rust); font: 700 14px/1.05 var(--mono); letter-spacing: .04em; }
.eyebrow { margin: 0 0 5px; color: var(--muted); font-size: 14px; letter-spacing: .1em; }
h1 { margin: 0; font: 700 clamp(34px, 7vw, 48px)/1.05 var(--display); letter-spacing: .06em; }
.login-intro { margin: 28px 0 30px; color: var(--muted); font-size: 15px; line-height: 1.8; }
label { display: block; margin-bottom: 9px; font-size: 13px; font-weight: 600; }
.password-row { display: flex; border: 1px solid var(--line); background: #fff; }
input { min-width: 0; flex: 1; padding: 15px 16px; border: 0; outline: 0; background: transparent; color: var(--ink); font: 16px/1.2 var(--text); }
.password-row:focus-within { border-color: var(--rust); box-shadow: 0 0 0 3px rgba(169, 62, 47, .12); }
.toggle-password { align-self: stretch; padding: 0 14px; border: 0; border-left: 1px solid var(--line); background: transparent; color: var(--muted); cursor: pointer; font-size: 12px; }
.toggle-password:hover, .toggle-password:focus-visible { color: var(--rust); }
.login-button { display: flex; width: 100%; align-items: center; justify-content: space-between; margin-top: 20px; padding: 16px 18px; border: 1px solid var(--rust); background: var(--rust); color: #fffaf5; cursor: pointer; font: 600 15px/1 var(--text); transition: background .18s ease, transform .18s ease; }
.login-button:hover { background: #8f3226; transform: translateY(-1px); }
.login-button:focus-visible { outline: 2px dashed var(--ink); outline-offset: 4px; }
.login-button:disabled { cursor: wait; opacity: .65; }
.login-button span { font-size: 23px; font-weight: 400; }
.login-error { margin: 12px 0 0; color: #9a362c; font-size: 13px; line-height: 1.5; }
.login-rule { display: flex; justify-content: space-between; gap: 20px; margin-top: 34px; padding-top: 15px; border-top: 1px dashed var(--line); color: var(--muted); font: 10px/1 var(--mono); letter-spacing: .08em; }
.login-note { margin: 13px 0 0; color: var(--muted); font-size: 12px; line-height: 1.7; }
.login-footer { margin: 20px 0 0; color: var(--muted); font: 10px/1 var(--mono); letter-spacing: .12em; text-align: center; }

@media (max-width: 520px) {
  .login-shell { padding: 16px; }
  .login-card { padding: 30px 24px; }
  .login-heading { margin-top: 32px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; }
}