:root {
  color-scheme: dark;
  --black: #000;
  --surface: #070707;
  --line: rgba(255, 255, 255, .14);
  --text: #f5f5f5;
  --muted: #858585;
  --danger: #ff7b7b;
}

* { box-sizing: border-box; }

body {
  min-height: 100vh;
  margin: 0;
  background:
    linear-gradient(rgba(255,255,255,.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.025) 1px, transparent 1px),
    radial-gradient(circle at 50% 12%, #111 0, var(--black) 42%);
  background-size: 42px 42px, 42px 42px, auto;
  color: var(--text);
  font: 14px/1.5 "Microsoft YaHei UI", "PingFang SC", sans-serif;
}

button, input { font: inherit; }

.login-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 28px;
}

.login-card {
  position: relative;
  width: min(390px, 100%);
  padding: 38px 36px 34px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(3, 3, 3, .94);
  box-shadow: 0 30px 100px rgba(0, 0, 0, .9), inset 0 1px rgba(255,255,255,.035);
  overflow: hidden;
}

.login-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,.6), transparent);
}

.lock-mark {
  position: relative;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  margin-bottom: 25px;
  border: 1px solid rgba(255,255,255,.22);
  border-radius: 12px;
  background: #060606;
}

.lock-mark::before {
  content: "";
  width: 14px;
  height: 11px;
  margin-top: 7px;
  border: 1.5px solid #d7d7d7;
  border-radius: 3px;
}

.lock-mark span {
  position: absolute;
  width: 11px;
  height: 10px;
  margin-top: -7px;
  border: 1.5px solid #d7d7d7;
  border-bottom: 0;
  border-radius: 7px 7px 0 0;
}

.eyebrow {
  margin: 0 0 8px;
  color: #777;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 2px;
}

h1 {
  margin: 0;
  font-size: 31px;
  line-height: 1.15;
  letter-spacing: -.8px;
  font-weight: 650;
}

.intro {
  margin: 9px 0 27px;
  color: var(--muted);
  font-size: 12px;
}

form { display: grid; }

label {
  margin-bottom: 7px;
  color: #a3a3a3;
  font-size: 11px;
  font-weight: 600;
}

input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 11px 12px;
  outline: 0;
  background: #000;
  color: var(--text);
  transition: border-color .15s ease, box-shadow .15s ease;
}

input:focus {
  border-color: rgba(255,255,255,.5);
  box-shadow: 0 0 0 3px rgba(255,255,255,.05);
}

button {
  margin-top: 13px;
  border: 1px solid #fff;
  border-radius: 9px;
  padding: 11px 14px;
  background: #fff;
  color: #000;
  font-weight: 750;
  cursor: pointer;
  transition: background .15s ease, color .15s ease, transform .15s ease;
}

button:hover { background: #000; color: #fff; transform: translateY(-1px); }
button:disabled { opacity: .55; cursor: wait; transform: none; }

.error {
  margin: 12px 0 0;
  padding: 9px 10px;
  border: 1px solid rgba(255,123,123,.3);
  border-radius: 8px;
  background: rgba(255,123,123,.06);
  color: var(--danger);
  font-size: 11px;
}

.hidden { display: none !important; }

@media (max-width: 520px) {
  .login-shell { padding: 18px; }
  .login-card { padding: 31px 24px 25px; border-radius: 15px; }
  h1 { font-size: 27px; }
}