:root {
  --rk-primary: #590694;
  --rc-primary: #FF8C00;
  --white: #ffffff;
  --glass-bg: rgba(255, 255, 255, 0.1);
}

body, html {
  height: 100%;
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
}
.back-arrow {
  color: #0d6efd;
  font-weight: 500;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 15px;
  transition: 0.3s;
}

.back-arrow:hover {
  color: #084298;
  text-decoration: underline;
}

.portal-container {
  height: 100vh;
}

.portal-left {
  background: linear-gradient(135deg, var(--rk-primary), #000);
  width: 50%;
  padding: 2rem;
  text-align: center;
}

.portal-logo {
  width: 110px;
  height: 110px;
  object-fit: cover;
  border-radius: 50%;
  border: 2px solid #fff;
  box-shadow: 0 4px 10px rgba(0,0,0,0.4);
}

.portal-right {
  background: url('img/classroom.jpg') center/cover no-repeat;
  width: 50%;
  position: relative;
  backdrop-filter: blur(6px);
}

.login-card {
  background-color: rgba(255, 255, 255, 0.9);
  border-radius: 15px;
  width: 90%;
  max-width: 400px;
}

/* Responsive */
@media (max-width: 768px) {
  .portal-left {
    display: none !important;
  }

  .portal-right {
    width: 100%;
    background: linear-gradient(135deg, var(--rk-primary), #000);
  }

  .login-card {
    background-color: #fff;
    margin: 0 1rem;
  }
}