:root {
  color-scheme: dark;
  --bg: #07090e;
  --panel: #10141e;
  --line: rgba(123, 157, 222, 0.22);
  --text: #f6f8ff;
  --muted: #8b98b2;
  --blue: #3487ff;
  --danger: #ff7a90;
}

* { box-sizing: border-box; }

html, body { min-height: 100%; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 68% 24%, rgba(52, 135, 255, 0.16), transparent 25%),
    linear-gradient(rgba(111, 145, 210, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(111, 145, 210, 0.045) 1px, transparent 1px),
    var(--bg);
  background-size: auto, 64px 64px, 64px 64px, auto;
  color: var(--text);
  font-family: "Microsoft YaHei UI", "PingFang SC", "Segoe UI", sans-serif;
}

button, input { font: inherit; }

button:focus-visible,
input:focus-visible {
  outline: 2px solid #8db4ff;
  outline-offset: 3px;
}

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

.login-card {
  width: min(100%, 480px);
  padding: clamp(30px, 6vw, 54px);
  border: 1px solid var(--line);
  border-radius: 10px;
  background: linear-gradient(145deg, rgba(20, 25, 38, 0.98), rgba(9, 12, 19, 0.98));
  box-shadow: 0 32px 90px rgba(0, 0, 0, 0.42);
}

.brand { display: flex; align-items: center; gap: 13px; }
.brand > span:last-child { display: grid; gap: 2px; }
.brand strong { font-family: "Arial Narrow", Impact, sans-serif; font-size: 20px; letter-spacing: 0.08em; }
.brand small { color: #73809a; font-family: Consolas, monospace; font-size: 9px; letter-spacing: 0.15em; }

.brand-mark {
  display: flex;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  gap: 3px;
  border: 1px solid rgba(108, 155, 255, 0.4);
  border-radius: 50%;
  background: rgba(52, 135, 255, 0.08);
}

.brand-mark i { width: 5px; height: 5px; border-radius: 50%; background: #3487ff; box-shadow: 0 0 10px #3487ff; }
.brand-mark i:nth-child(2) { background: #ffb80c; box-shadow: 0 0 10px #ffb80c; }
.brand-mark i:nth-child(3) { background: #0ee860; box-shadow: 0 0 10px #0ee860; }

.login-heading { margin: 58px 0 34px; }
.login-heading > span { color: #6399f8; font-family: Consolas, monospace; font-size: 10px; font-weight: 800; letter-spacing: 0.13em; }
.login-heading h1 { margin: 13px 0 12px; font-size: clamp(34px, 8vw, 48px); line-height: 1.12; }
.login-heading p { min-height: 48px; margin: 0; color: var(--muted); font-size: 13px; line-height: 1.8; }

form { display: grid; gap: 20px; }
label { display: grid; gap: 9px; }
label span { color: #cbd5e9; font-size: 12px; font-weight: 800; }
input {
  width: 100%;
  height: 50px;
  padding: 0 15px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #080b12;
  color: white;
}
input:hover { border-color: rgba(92, 148, 255, 0.48); }

button {
  min-height: 52px;
  margin-top: 5px;
  border: 1px solid #4b91ff;
  border-radius: 6px;
  background: var(--blue);
  color: white;
  font-weight: 800;
  cursor: pointer;
}
button:hover { background: #4b94ff; }
button:disabled { cursor: wait; opacity: 0.7; }

.form-message { min-height: 22px; margin: -6px 0 0; color: var(--danger); font-size: 12px; line-height: 1.6; }
.login-card footer { display: flex; margin-top: 30px; align-items: center; gap: 8px; color: #65728a; font-size: 10px; }
.login-card footer i { width: 7px; height: 7px; border-radius: 50%; background: #4bd2a3; box-shadow: 0 0 12px rgba(75, 210, 163, 0.75); }

@media (max-width: 540px) {
  .login-shell { padding: 16px; }
  .login-card { padding: 30px 24px; }
  .login-heading { margin-top: 44px; }
}