* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}

body {
  background-color: #212121;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.text-wrapper {
  display: flex;
  gap: clamp(4px, 1.5vw, 14px);
  justify-content: center;
  align-items: center;
  padding: 20px;
  perspective: 600px;
}

.letter {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  width: clamp(36px, 10vw, 72px);
  height: clamp(60px, 17vw, 120px);
  border-radius: clamp(4px, 1vw, 10px);
  box-shadow: inset 0 0 10px 6px rgba(0, 0, 0, 0.4);
  color: #ffffff;
  font-size: clamp(18px, 5.5vw, 42px);
  font-weight: 400;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  user-select: none;
  overflow: hidden;
  transform-style: preserve-3d;
}

.letter::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: rgba(0, 0, 0, 0.4);
  transform: translateY(-50%);
  pointer-events: none;
}

.letter span {
  display: inline-block;
  perspective: 300px;
}

.letter span.flip {
  animation: flipLetter 0.1s ease-in-out forwards;
}

@keyframes flipLetter {
  0%   { transform: rotateX(0deg); }
  49%  { transform: rotateX(-90deg); }
  50%  { transform: rotateX(90deg); }
  100% { transform: rotateX(0deg); }
}

.footer {
  position: fixed;
  bottom: 24px;
  left: 0;
  width: 100%;
  text-align: center;
}

.footer a {
  color: rgba(255, 255, 255, 0.25);
  font-size: 13px;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  text-decoration: none;
  letter-spacing: 0.05em;
}

.footer a:hover {
  color: rgba(255, 255, 255, 0.5);
}