* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', Roboto, sans-serif;
  background: #0a0e17;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  overflow: hidden;
}

/* 背景装饰 — 鹰角风格的光晕 */
body::before {
  content: '';
  position: fixed;
  top: -30%;
  left: -20%;
  width: 70%;
  height: 80%;
  background: radial-gradient(ellipse at center, rgba(0,120,255,0.08) 0%, transparent 70%);
  pointer-events: none;
}

body::after {
  content: '';
  position: fixed;
  bottom: -20%;
  right: -10%;
  width: 60%;
  height: 60%;
  background: radial-gradient(ellipse at center, rgba(0,180,255,0.06) 0%, transparent 70%);
  pointer-events: none;
}

.login-container {
  width: 100%;
  max-width: 420px;
  padding: 20px;
  position: relative;
  z-index: 1;
}

.login-box {
  background: rgba(18, 24, 38, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 16px;
  padding: 44px 40px;
  box-shadow: 0 8px 48px rgba(0,0,0,0.4), inset 0 1px 0 rgba(255,255,255,0.04);
}

.login-box h1 {
  font-size: 22px;
  color: #fff;
  text-align: center;
  margin-bottom: 32px;
  font-weight: 600;
  letter-spacing: 0.5px;
}

/* Tabs — 深色风格 */
.tabs {
  display: flex;
  gap: 0;
  margin-bottom: 28px;
  background: rgba(255,255,255,0.04);
  border-radius: 10px;
  padding: 3px;
  border: 1px solid rgba(255,255,255,0.04);
}

.tab {
  flex: 1;
  padding: 10px;
  border: none;
  background: transparent;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  color: rgba(255,255,255,0.4);
  transition: all 0.25s ease;
}

.tab.active {
  background: rgba(0,120,255,0.15);
  color: #60b0ff;
  font-weight: 600;
  box-shadow: 0 0 20px rgba(0,120,255,0.05);
}

.form { display: none; }
.form.active { display: block; }

.input-group {
  margin-bottom: 20px;
}

.input-group label {
  display: block;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
  margin-bottom: 6px;
  font-weight: 500;
  letter-spacing: 0.3px;
  text-transform: uppercase;
}

.input-group input {
  width: 100%;
  padding: 12px 16px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 10px;
  font-size: 15px;
  color: #fff;
  transition: all 0.25s ease;
  outline: none;
}

.input-group input::placeholder {
  color: rgba(255,255,255,0.2);
}

.input-group input:focus {
  border-color: rgba(0,120,255,0.5);
  background: rgba(0,120,255,0.04);
  box-shadow: 0 0 0 3px rgba(0,120,255,0.06), 0 0 30px rgba(0,120,255,0.03);
}

.btn-submit {
  width: 100%;
  padding: 12px;
  background: linear-gradient(135deg, #0078ff, #0060cc);
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.25s ease;
  margin-top: 8px;
  letter-spacing: 2px;
  position: relative;
  overflow: hidden;
}

.btn-submit:hover {
  background: linear-gradient(135deg, #1a88ff, #0070dd);
  box-shadow: 0 4px 24px rgba(0,120,255,0.25);
  transform: translateY(-1px);
}

.btn-submit:active {
  transform: translateY(0);
}

.btn-submit:disabled {
  background: rgba(255,255,255,0.06);
  color: rgba(255,255,255,0.2);
  box-shadow: none;
  cursor: not-allowed;
  transform: none;
}

.msg {
  margin-top: 16px;
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 13px;
  text-align: center;
  display: none;
  backdrop-filter: blur(10px);
}

.msg.error {
  display: block;
  background: rgba(255,50,50,0.1);
  color: #ff6b6b;
  border: 1px solid rgba(255,50,50,0.15);
}

.msg.success {
  display: block;
  background: rgba(50,200,100,0.1);
  color: #4cd988;
  border: 1px solid rgba(50,200,100,0.15);
}