:root {
  color-scheme: light;
  --navy: #0f172a;
  --muted: #64748b;
  --line: #dbe3ef;
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --surface: #ffffff;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  color: var(--navy);
  background: #f3f6fb;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.login-shell {
  display: grid;
  min-height: 100vh;
  place-items: center;
  padding: 24px;
}
.login-card {
  width: min(100%, 420px);
  padding: 36px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  box-shadow: 0 24px 70px rgb(15 23 42 / 10%);
}
.brand {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border-radius: 14px;
  color: white;
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  font-weight: 800;
  letter-spacing: -.03em;
}
.copy { margin: 24px 0 28px; }
h1 { margin: 0; font-size: 1.75rem; letter-spacing: -.03em; }
.copy p, .signed-in p { margin: 8px 0 0; color: var(--muted); }
.login-form, .signed-in, .signed-in form { display: grid; gap: 12px; }
label { margin-top: 4px; font-size: .875rem; font-weight: 650; }
input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid #cbd5e1;
  border-radius: 10px;
  color: var(--navy);
  background: white;
  font: inherit;
}
input:focus { outline: 2px solid #93c5fd; border-color: var(--blue); }
button, .primary-link {
  min-height: 44px;
  border: 0;
  border-radius: 10px;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}
.primary-button, .primary-link {
  display: grid;
  margin-top: 8px;
  place-items: center;
  color: white;
  background: var(--blue);
  text-decoration: none;
}
.primary-button:hover, .primary-link:hover { background: var(--blue-dark); }
.secondary-button { color: var(--navy); background: #e2e8f0; }
.error {
  margin-bottom: 18px;
  padding: 11px 13px;
  border: 1px solid #fecaca;
  border-radius: 10px;
  color: #991b1b;
  background: #fef2f2;
  font-size: .9rem;
}
@media (max-width: 520px) {
  .login-shell { padding: 14px; }
  .login-card { padding: 26px 22px; border-radius: 16px; }
}