* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Poppins, sans-serif;
}

body {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: url('https://images.unsplash.com/photo-1524253482453-3fed8d2fe12b') no-repeat center/cover;
  transition: 0.4s ease;
}

body.dark {
  background: #0e0e0e;
}

.container {
  width: 350px;
  padding: 30px;
  text-align: center;
  border-radius: 25px;
  backdrop-filter: blur(15px);
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
  color: white;
}

body.dark .container {
  background: rgba(40, 40, 40, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

h2 {
  font-size: 26px;
  margin-bottom: 20px;
}

.input-box {
  position: relative;
  margin: 25px 0;
}

.input-box input {
  width: 100%;
  padding: 12px 40px 12px 40px;
  background: transparent;
  border: none;
  border-bottom: 2px solid #ddd;
  font-size: 15px;
  outline: none;
  color: white;
  transition: 0.3s;
}

.input-box label {
  position: absolute;
  left: 40px;
  bottom: 12px;
  color: #eee;
  transition: 0.3s;
  pointer-events: none;
}

.input-box input:focus,
.input-box input:valid {
  border-color: #00eaff;
}

.input-box input:focus+label,
.input-box input:valid+label {
  transform: translateY(-22px);
  font-size: 12px;
  color: #00eaff;
}

.input-box .icon {
  position: absolute;
  left: 10px;
  bottom: 12px;
  color: #eee;
  font-size: 18px;
}

.btn {
  width: 100%;
  background: #00eaff;
  padding: 12px;
  border: none;
  color: #000;
  border-radius: 15px;
  font-size: 17px;
  cursor: pointer;
  margin-top: 10px;
  transition: 0.3s;
  font-weight: bold;
}

.btn:hover {
  background: #00b7cc;
}

.text {
  margin-top: 15px;
}

.text a {
  color: #00eaff;
  text-decoration: none;
  font-weight: 500;
}

.theme-toggle {
  position: absolute;
  top: 25px;
  right: 25px;
  background: rgba(255, 255, 255, 0.3);
  padding: 10px;
  border-radius: 50%;
  cursor: pointer;
  backdrop-filter: blur(5px);
  color: white;
  transition: 0.3s;
}

.theme-toggle:hover {
  background: rgba(255, 255, 255, 0.5);
}

@media (max-width: 450px) {
  .container {
    width: 90%;
  }
}