body.background-image {
  background-image: url("https://images.pexels.com/photos/66997/pexels-photo-66997.jpeg");
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  position: relative;
  min-height: 100vh;
}
body.background-image::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(255,255,255,0.6);
  pointer-events: none;
  z-index: -1;
}
body.dark-mode.background-image::before {
  background: rgba(0,0,0,0.5);
}
.right-align {
    text-align: right;
}
.center-align {
    text-align: center;
}
.toggle-btn {
    box-shadow: 10px;
    padding: 10px;
    text-align: center;
    border: none;
    cursor: pointer;
}
.box1{
    text-align: center;
    border-width: 5px;
    padding: 50px;
}
.box2{
    text-align: center;
    border-width: 5px;
    padding: 100px;
}
body{
    background-color: #ffffff;
    color: #000000;
    transition: background-color 0.3s ease, color 0.3s ease;
}
button#modeToggle {
    padding: 10px 10px;
    cursor: pointer;
}
body.dark-mode {
    background-color: #121212;
    color: #ffffff;
}
body.dark-mode button#modeToggle {
    background-color: #333333;
    color: #ffffff;
    border: 1px solid #ffffff;
}
.copy-msg {
    padding: 10px;
    color: green;
    text-align: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}
.copy-msg.show {
    opacity: 1;
}
.spinner {
    border: 6px solid #f3f3f3;
    border-top: 6px solid #3498db;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}