:root {
  color-scheme: light;
  --ink: #152019;
  --muted: #68766e;
  --line: #d8e0da;
  --paper: #ffffff;
  --wash: #f4f6f3;
  --accent: #18764b;
  --accent-strong: #0f5d39;
  --red: #a33a32;
  --font-primitive-12: 12px;
  --font-primitive-14: 14px;
  --font-primitive-16: 16px;
  --font-primitive-20: 20px;
  --font-primitive-24: 24px;
  --font-caption: var(--font-primitive-12);
  --font-control: var(--font-primitive-14);
  --font-body: var(--font-primitive-16);
  --font-panel-title: var(--font-primitive-20);
  --font-page-title: var(--font-primitive-24);
  font-family: "Segoe UI Variable", "PingFang SC", "Microsoft YaHei", sans-serif;
}
* { box-sizing: border-box; }
body {
  display: grid;
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  padding: 2rem;
  place-items: center;
  color: var(--ink);
  background:
    radial-gradient(circle at 20% 15%, rgba(24, 118, 75, .12), transparent 34rem),
    var(--wash);
  font-size: var(--font-body);
  line-height: 1.6;
}

button, input { font: inherit; }
.auth-shell { width: min(100%, 440px); }
.brand { margin-bottom: 1.25rem; text-align: center; }
.brand p { margin: 0 0 .25rem; color: var(--accent); font-size: var(--font-caption); font-weight: 800; letter-spacing: .14em; }
.brand h1 { margin: 0; font-size: var(--font-page-title); line-height: 1.25; }
.auth-card { padding: 2rem; border: 1px solid var(--line); border-radius: 20px; background: var(--paper); box-shadow: 0 18px 50px rgba(31, 52, 40, .09); }
.auth-card h2 { margin: 0 0 .4rem; font-size: var(--font-panel-title); }
.auth-card > p { margin: 0 0 1.5rem; color: var(--muted); }
.auth-form { display: grid; gap: 1rem; }
.auth-form label { display: grid; gap: .4rem; color: var(--ink); font-size: var(--font-control); font-weight: 700; }
.auth-form input { width: 100%; min-height: 44px; padding: .7rem .8rem; border: 1px solid var(--line); border-radius: 9px; color: var(--ink); background: white; font-size: var(--font-body); }
.auth-form input:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.auth-form button { min-height: 44px; margin-top: .25rem; border: 0; border-radius: 9px; color: white; background: var(--accent-strong); font-size: var(--font-control); font-weight: 800; cursor: pointer; }
.auth-form button:disabled { cursor: wait; opacity: .65; }
.auth-status { min-height: 1.6em; margin: 1rem 0 0; color: var(--muted); font-size: var(--font-control); }
.auth-status[data-tone="error"] { color: var(--red); }
.invitation-summary { display: grid; gap: .3rem; margin: 0 0 1.25rem; padding: .9rem 1rem; border-radius: 10px; background: var(--wash); }
.invitation-summary strong { font-size: var(--font-body); }
.invitation-summary span { color: var(--muted); font-size: var(--font-control); }
.password-hint { color: var(--muted); font-size: var(--font-caption); font-weight: 400; }

@media (max-width: 560px) {
  body { padding: 1rem; }
  .auth-card { padding: 1.4rem; }
}