html, body { 
    height: 100%; 
    margin: 0; 
}

.banner {
  position: relative;
  min-height: 100dvh;
  min-height: 100vh;   
  overflow: hidden;
}

.banner::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url('../images/background.png');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  z-index: 0;
}

.banner-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.65);
  z-index: 1;
}

.banner-content { 
    position: relative; 
    z-index: 2; 
}

.form-element.glass {
  background: rgba(255, 255, 255, 0.18);
  border: 1px solid rgba(255, 255, 255, 0.28);
  color: #fff;
  border-radius: 0.5rem;
  padding: 1rem 1.25rem;
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.2), 0 2px 6px rgba(0, 0, 0, 0.15);
  width: 100%;
  font-size: 1rem;
}

.form-element.glass::placeholder {
  color: rgba(255, 255, 255, 0.9);
}

.form-element.glass:focus {
  border-color: rgba(255, 255, 255, 0.6);
  background: rgba(255, 255, 255, 0.25);
  color: #fff;
  box-shadow: 0 0 0 0.2rem rgba(255, 255, 255, 0.1);
}

.form-container {
  max-width: 700px;
  margin: 0 auto;
}

.btn-join {
  background-color: #2196f3;
  color: #fff;
  font-weight: 700;
  text-transform: uppercase;
  border: none;
  border-radius: 50px;
  padding: 0.9rem 3rem;
  font-size: 1.1rem;
  transition: all 0.25s ease-in-out;
}

.btn-join:hover {
  background-color: #0b7dda;
  transform: translateY(-2px);
}

.btn-join:active {
  transform: scale(0.98);
}