:root {
  --bg: #06152d;
  --border: rgba(82, 170, 255, 0.32);
  --text: #e8f3ff;
  --text-soft: #9fc4f3;
  --title: #ffffff;
  --shadow: 0 18px 48px rgba(0, 0, 0, 0.28);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: Arial, "Microsoft YaHei", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 18% 8%, rgba(57, 124, 255, 0.22), transparent 28%),
    radial-gradient(circle at 82% 12%, rgba(60, 220, 255, 0.18), transparent 24%),
    linear-gradient(180deg, #041227 0%, #071a35 42%, #06152d 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

body:before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 36px 36px;
  opacity: 0.35;
}

.login-card {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 500px;
  border: 1px solid var(--border);
  border-radius: 28px;
  background:
    radial-gradient(circle at 80% 20%, rgba(62, 199, 255, 0.20), transparent 24%),
    linear-gradient(135deg, rgba(9, 34, 82, 0.96), rgba(4, 20, 46, 0.98));
  box-shadow: var(--shadow);
  padding: 34px;
  overflow: hidden;
}

.login-card:after {
  content: "";
  position: absolute;
  right: -60px;
  top: -60px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(91, 212, 255, 0.32), transparent 68%);
  filter: blur(6px);
}

.content {
  position: relative;
  z-index: 1;
}

.logo {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  background: linear-gradient(180deg, rgba(66,178,255,0.28), rgba(66,178,255,0.08));
  border: 1px solid rgba(66,178,255,0.25);
  box-shadow: inset 0 0 12px rgba(66,178,255,0.08);
  font-size: 26px;
}

h1 {
  margin: 0 0 10px;
  font-size: 34px;
  color: var(--title);
  font-weight: 900;
}

.subtitle {
  color: var(--text-soft);
  line-height: 1.8;
  font-size: 14px;
  margin-bottom: 24px;
}

.form-item { margin-bottom: 16px; }

label {
  display: block;
  margin-bottom: 8px;
  color: #dbedff;
  font-size: 14px;
  font-weight: 800;
}

input {
  width: 100%;
  height: 46px;
  border-radius: 14px;
  border: 1px solid rgba(94, 176, 255, 0.25);
  background: rgba(8, 29, 66, 0.82);
  color: #f4fbff;
  padding: 0 16px;
  outline: none;
  font-size: 15px;
  transition: all 0.18s ease;
}

input::placeholder { color: #7ea9d8; }

input:focus {
  border-color: rgba(101, 211, 255, 0.52);
  box-shadow: 0 0 0 4px rgba(68, 182, 255, 0.12);
}

button {
  width: 100%;
  height: 46px;
  margin-top: 6px;
  border: none;
  border-radius: 14px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 900;
  color: #fff;
  background: linear-gradient(180deg, #2e98ff, #1f73ff);
  box-shadow: 0 10px 20px rgba(25, 118, 255, 0.18);
  transition: all 0.18s ease;
}

button:hover:not(:disabled) {
  transform: translateY(-1px);
  filter: brightness(1.04);
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.message {
  min-height: 24px;
  margin-top: 16px;
  color: var(--text-soft);
  line-height: 1.7;
  font-size: 13px;
}

.message.error { color: #ffb6c1; }
.message.success { color: #90ffd1; }

.tip {
  margin-top: 18px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid rgba(102, 216, 255, 0.24);
  background: rgba(102, 216, 255, 0.08);
  color: #c9f4ff;
  line-height: 1.8;
  font-size: 13px;
}