body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #0b1c2d;
  color: #ffffff;
}


.deck {
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.slide {
  display: none;
  text-align: center;
  max-width: 800px;
  padding: 40px;
  animation: fade 0.5s ease;
}

.slide.active {
  display: block;
}

h1 {
  font-size: 64px;
  margin-bottom: 10px;
}

h2 {
  color: #4da6ff;
}

ul, ol {
  text-align: left;
  display: inline-block;
  margin-top: 20px;
  

}
ul li {
  margin-bottom: 10px;
}
ol li {
  margin-bottom: 10px;
}
.live-value {
  font-size: 36px;
  color: #00ffcc;
  margin: 20px 0;
}

.formula {
  background: #12263a;
  padding: 15px;
  border-radius: 8px;
  margin-top: 20px;
  font-family: monospace;
}

.controls {
  position: fixed;
  bottom: 20px;
  width: 100%;
  text-align: center;
}

.controls button {
  background: #4da6ff;
  border: none;
  padding: 10px 20px;
  margin: 0 10px;
  font-size: 18px;
  cursor: pointer;
  border-radius: 6px;
}

#counter {
  font-weight: bold;
}

@keyframes fade {
  from {opacity: 0;}
  to {opacity: 1;}
}

.back-button {
  position: fixed;
  top: 20px;
  left: 20px;
  z-index: 1000;

  padding: 10px 16px;
  background: rgba(10, 37, 64, 0.85);
  color: #ffffff;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;

  border-radius: 8px;
  backdrop-filter: blur(6px);
  border: 1px solid rgba(255, 255, 255, 0.15);

  transition: all 0.25s ease;
}

.back-button:hover {
  background: linear-gradient(135deg, #1a73e8, #0a2540);
  box-shadow: 0 8px 24px rgba(26, 115, 232, 0.35);
  transform: translateY(-1px);
}