:root {
  color-scheme: light dark;
  --bg-main: #f6f6f7;
  --text-main: #111111;
  --text-muted: #666666;
  --card-bg: rgba(255, 255, 255, 0.92);
  --card-border: rgba(0, 0, 0, 0.08);
  --card-shadow-1: rgba(0, 0, 0, 0.04);
  --card-shadow-2: rgba(0, 0, 0, 0.08);
  --field-bg: #ffffff;
  --field-border: rgba(0, 0, 0, 0.14);
  --field-border-focus: rgba(0, 0, 0, 0.35);
  --field-focus-ring: rgba(0, 0, 0, 0.08);
  --btn-bg: #ffffff;
  --btn-border: rgba(0, 0, 0, 0.16);
  --btn-bg-hover: #f3f3f3;
  --btn-primary-bg: #111111;
  --btn-primary-border: #000000;
  --btn-primary-text: #ffffff;
  --link: #5a5a5a;
  --link-hover: #111111;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-main: #0f1012;
    --text-main: #ededee;
    --text-muted: #a7a8ab;
    --card-bg: rgba(24, 25, 28, 0.88);
    --card-border: rgba(255, 255, 255, 0.14);
    --card-shadow-1: rgba(0, 0, 0, 0.42);
    --card-shadow-2: rgba(0, 0, 0, 0.32);
    --field-bg: #1d1f23;
    --field-border: rgba(255, 255, 255, 0.2);
    --field-border-focus: rgba(255, 255, 255, 0.4);
    --field-focus-ring: rgba(255, 255, 255, 0.12);
    --btn-bg: #1d1f23;
    --btn-border: rgba(255, 255, 255, 0.2);
    --btn-bg-hover: #25282d;
    --btn-primary-bg: #f4f4f5;
    --btn-primary-border: #ffffff;
    --btn-primary-text: #101112;
    --link: #c2c3c7;
    --link-hover: #ffffff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Geist", "Geist Sans", "Inter", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background:
    radial-gradient(900px 500px at 20% -10%, rgba(0, 0, 0, 0.08), transparent),
    radial-gradient(900px 500px at 100% 120%, rgba(0, 0, 0, 0.06), transparent),
    var(--bg-main);
  color: var(--text-main);
  padding: 20px;
}

.stack {
  width: min(94vw, 420px);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.top-link {
  align-self: center;
  font-size: 0.86rem;
  color: var(--link);
  text-decoration: none;
  letter-spacing: 0.01em;
}

.top-link:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

.card {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  box-shadow:
    0 1px 1px var(--card-shadow-1),
    0 8px 32px var(--card-shadow-2);
  padding: 24px;
  backdrop-filter: blur(8px);
}

h1 {
  margin: 0 0 6px;
  font-size: 1.45rem;
  font-weight: 680;
  letter-spacing: -0.01em;
}

p {
  margin: 0 0 18px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.error {
  margin-bottom: 14px;
  border-radius: 10px;
  border: 1px solid #f1b8bc;
  background: #fff3f4;
  color: #9f1a2c;
  padding: 10px 12px;
  font-size: 0.88rem;
}

label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.88rem;
  font-weight: 620;
}

.row {
  display: flex;
  gap: 8px;
}

input[type="password"],
input[type="text"] {
  flex: 1;
  height: 42px;
  border: 1px solid var(--field-border);
  border-radius: 10px;
  background: var(--field-bg);
  color: var(--text-main);
  padding: 0 12px;
  font-size: 0.95rem;
  font-family: inherit;
  font-weight: 500;
  outline: none;
  transition: border-color 140ms ease, box-shadow 140ms ease;
}

input[type="password"]:focus,
input[type="text"]:focus {
  border-color: var(--field-border-focus);
  box-shadow: 0 0 0 3px var(--field-focus-ring);
}

button {
  border: 1px solid var(--btn-border);
  background: var(--btn-bg);
  color: var(--text-main);
  border-radius: 10px;
  cursor: pointer;
  height: 42px;
  padding: 0 12px;
  font-size: 0.88rem;
  font-weight: 580;
  font-family: inherit;
}

#toggle {
  width: 64px;
  min-width: 64px;
}

button:hover {
  background: var(--btn-bg-hover);
}

button[type="submit"] {
  margin-top: 12px;
  width: 100%;
  border: 1px solid var(--btn-primary-border);
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  font-weight: 620;
  letter-spacing: 0.01em;
}

button[type="submit"]:hover {
  opacity: 0.92;
}