/* SRTech - Trang đăng nhập Admin */

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.login-container {
  background: white;
  border-radius: 20px;
  padding: 50px 40px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
  max-width: 450px;
  width: 100%;
  position: relative;
  overflow: hidden;
}

.login-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, #667eea, #764ba2);
}

.login-header {
  text-align: center;
  margin-bottom: 40px;
}

.login-header h1 {
  color: #333;
  font-size: 2.5em;
  margin-bottom: 10px;
  font-weight: 600;
}

.login-header p {
  color: #666;
  font-size: 1.1em;
}

.logo {
  width: 80px;
  height: auto;
  margin-bottom: 20px;
}

.form-group {
  margin-bottom: 25px;
}

.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 8px;
  color: #333;
  font-size: 1em;
}

.form-group input {
  width: 100%;
  padding: 15px 20px;
  border: 2px solid #e1e5e9;
  border-radius: 10px;
  font-size: 1em;
  transition: all 0.3s ease;
  background: #fafbfc;
}

.form-group input:focus {
  outline: none;
  border-color: #667eea;
  background: white;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group input[type="password"] {
  font-family: password;
}

.login-button {
  width: 100%;
  padding: 18px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 1.1em;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.login-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
}

.login-button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.alert {
  padding: 15px;
  border-radius: 8px;
  margin-bottom: 20px;
  font-weight: 600;
  text-align: center;
}

.alert-danger {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.alert-success {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.alert-warning {
  background: #fff3cd;
  color: #856404;
  border: 1px solid #ffeaa7;
}

.password-toggle {
  position: relative;
}

.password-toggle button {
  position: absolute;
  right: 15px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: #666;
  cursor: pointer;
  font-size: 1.1em;
  padding: 5px;
}

.loading-spinner {
  display: none;
  width: 20px;
  height: 20px;
  border: 2px solid #ffffff40;
  border-top: 2px solid #ffffff;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-right: 10px;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.back-link {
  text-align: center;
  margin-top: 20px;
}

.back-link a {
  color: #667eea;
  text-decoration: none;
  font-weight: 600;
}

.back-link a:hover {
  text-decoration: underline;
}

@media (max-width: 480px) {
  .login-container {
    margin: 10px;
    padding: 30px 20px;
  }

  .login-header h1 {
    font-size: 2em;
  }
}