* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #6e8efb, #a777e3);
  padding: 20px;
}

form {
  background: rgba(255, 255, 255, 0.9);
  padding: 40px;
  border-radius: 10px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
  width: 100%;
  max-width: 400px;
  transition: transform 0.3s ease;
}

form:hover {
  transform: translateY(-5px);
}

h2 {
  color: #333;
  margin-bottom: 30px;
  text-align: center;
  font-size: 2em;
}

label {
  display: block;
  margin-bottom: 8px;
  color: #555;
  font-weight: 500;
}

input[type="text"],
input[type="password"] {
  width: 100%;
  padding: 12px;
  border: 2px solid #ddd;
  border-radius: 6px;
  margin-bottom: 20px;
  transition: border-color 0.3s ease;
}

input[type="text"]:focus,
input[type="password"]:focus {
  border-color: #6e8efb;
  outline: none;
}

input[type="submit"] {
  width: 100%;
  padding: 12px;
  background: #6e8efb;
  color: white;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 600;
  transition: background 0.3s ease;
}

input[type="submit"]:hover {
  background: #5c7cfa;
}

.dark-mode-toggle {
  position: absolute;
  top: 20px;
  right: 20px;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  padding: 10px;
  border-radius: 50%;
  transition: background 0.3s ease;
}

.dark-mode-toggle:hover {
  background: rgba(255, 255, 255, 0.2);
}

.dark-mode {
  background: linear-gradient(135deg, #2b5876, #4e4376);
}

.dark-mode form {
  background: rgba(30, 30, 30, 0.9);
}

.dark-mode h2,
.dark-mode label {
  color: #fff;
}

.dark-mode input[type="text"],
.dark-mode input[type="password"] {
  background: rgba(255, 255, 255, 0.1);
  border-color: #444;
  color: white;
}