:root {
  --bg: #0f0f0f;
  --text: #00ffff;
  --glass: rgba(255, 255, 255, 0.05);
  --button-bg: rgba(255, 255, 255, 0.1);
}
body.light {
  --bg: #f1f1f1;
  --text: #333;
  --glass: rgba(255, 255, 255, 0.7);
  --button-bg: rgba(0, 0, 0, 0.05);
}
body {
  margin: 0;
  padding: 10px;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: linear-gradient(-45deg, #0f0f0f, #1a1a1a, #000, #0f0f0f);
  background-size: 400% 400%;
  animation: gradientMove 20s ease infinite;
  font-family: 'Segoe UI', sans-serif;
  color: var(--text);
  transition: background 0.3s ease;
  
}
@keyframes gradientMove {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.welcome-text {
  position: absolute;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--text);
  font-size: 1.5em;
  text-align: center;
  z-index: 2;
}
.calculator {
  backdrop-filter: blur(15px);
  background: var(--glass);
  border-radius: 20px;
  padding: 20px;
  box-shadow: 0 0 30px rgba(0, 255, 255, 0.2);
  z-index: 1;
  
}
.display {
  width: 100%;
  height: 60px;
  background: rgba(0, 0, 0, 0.4);
  color: var(--text);
  font-size: 2em;
  border: none;
  border-radius: 10px;
  padding:5px;
  text-align: right;
  margin-bottom: 15px;
}
.buttons {
  display: grid;
  grid-template-columns: repeat(4, 65px);
  grid-gap: 10px;
  /* justify-content:center ; */
}
button {
  height: 60px;
  width: 60px;
  font-size: 1.5em;
  border: none;
  border-radius: 10px;
  color: var(--text);
  background: var(--button-bg);
  box-shadow: 0 0 8px var(--text);
  cursor: pointer;
  transition: all 0.1s ease;
  position: relative;
  overflow: hidden;
  
}
button:hover {
  box-shadow: 0 0 15px var(--text), inset 0 0 5px var(--text);
  transform: scale(1.05);
}
button:active {
  transform: scale(0.95);
}
.theme-toggle {
  position: absolute;
  top: 10px;
  right: 20px;
  display: flex;
  gap: 10px;
}
.theme-toggle button {
  padding: 10px;
  border-radius: 50%;

h1{
    color: var(--text);
    font-size: 1.2em;
    margin-bottom: 10px;
    text-align: center;
  }
 
}
.history {
  position: absolute;
  right: 550px;
  top: 250px;
 
  
  background: var(--glass);
  border-radius: 10px;
  padding: 22px;
  max-height: 150px;
  overflow-y: auto;
  width: 50px;
  font-size: 0.9em;
  box-shadow: 0 0 10px rgba(0,255,255,0.2);
  margin-bottom: 150px;
  z-index: 4;
  
 
  
}
.history div {
  margin-bottom: 5px;
  padding-bottom: 100px;
  cursor: pointer; 
  
   

   

  

}