/* ...existing code... */
body {
  min-height: 100vh;
  background: linear-gradient(120deg, #0f2027, #2c5364, #00c6ff, #43e97b 100%);
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: "Segoe UI", "Roboto", Arial, sans-serif;
}
.calcu-lator {
  margin-top: 40px;
  height: 500px;
  width: 400px;
  background: rgba(255, 255, 255, 0.15);
  box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 2px solid rgba(255, 255, 255, 0.18);
  border-radius: 25px;
  display: grid;
  transition: box-shadow 0.3s;
}
.calcu-lator:hover {
  box-shadow: 0 16px 40px 0 rgba(31, 38, 135, 0.45), 0 1.5px 8px 0 #00c6ff;
}
.input-screen {
  border-radius: 10px;
  margin: 18px 12px 0 12px;
  height: 50px;
  width: 370px;
  color: #222;
  background: rgba(255, 255, 255, 0.7);
  font-size: 1.5rem;
  font-weight: 600;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  border: none;
  outline: none;
  padding: 15px;
  transition: box-shadow 0.2s, background 0.2s;
}
.input-screen:focus {
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 4px 16px #43e97b55;
}
.btn-container {
  height: 335px;
  width: 380px;
  margin-top: 15px;
  margin-left: 10px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 10px;
}
.btns {
  background: linear-gradient(135deg, #20ac99 40%, #00c6ff 100%);
  color: #fff;
  cursor: pointer;
  height: 55px;
  width: 55px;
  font-size: 1.3rem;
  border: none;
  border-radius: 12px;
  margin: 10px;
  font-weight: 900;
  box-shadow: 0 2px 8px rgba(32, 172, 153, 0.18);
  transition: background 0.3s, color 0.2s, transform 0.15s, box-shadow 0.2s;
  position: relative;
  overflow: hidden;
}
.btns::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.3s, height 0.3s;
  z-index: 0;
}
.btns:hover {
  background: linear-gradient(135deg, #43e97b 40%, #38f9d7 100%);
  color: #222;
  transform: scale(1.08) rotate(-2deg);
  box-shadow: 0 6px 24px #43e97b55;
}
.btns:active {
  background: linear-gradient(135deg, #0f2027 40%, #2c5364 100%);
  color: #fff;
  transform: scale(0.97);
}
.btns:hover::after {
  width: 120px;
  height: 120px;
}
.btns:focus {
  outline: 2px solid #00c6ff;
  outline-offset: 2px;
}
.btns.special {
  background: linear-gradient(135deg, #ffb347 40%, #ffcc33 100%);
  color: #222;
  box-shadow: 0 2px 8px #ffcc3355;
}
.btns.special:hover {
  background: linear-gradient(135deg, #ffcc33 40%, #ffe066 100%);
  color: #fff;
  box-shadow: 0 6px 24px #ffe06688;
}
.btns.equal {
  background: linear-gradient(135deg, #ff5858 40%, #f09819 100%);
  color: #fff;
  box-shadow: 0 2px 8px #f0981955;
}
.btns.equal:hover {
  background: linear-gradient(135deg, #f09819 40%, #ff5858 100%);
  color: #fff;
  box-shadow: 0 6px 24px #ff585888;
}
::-webkit-scrollbar {
  width: 8px;
  background: #2c5364;
}
::-webkit-scrollbar-thumb {
  background: #20ac99;
  border-radius: 8px;
}
/* ...existing code... */
.calc-heading {
  text-align: center;
  font-size: 2.2rem;
  font-weight: 900;
  letter-spacing: 2px;
  margin-top: 12px;
  margin-bottom: 3px;
  color: #fff;
  background: linear-gradient(90deg, #00c6ff 10%, #43e97b 90%);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 2px 8px #00c6ff88);
  text-shadow: 0 2px 8px #43e97b55;
  transition: letter-spacing 0.3s cubic-bezier(0.68, -0.55, 0.27, 1.55),
    filter 0.3s, text-shadow 0.3s;
  cursor: pointer;
  user-select: none;
  animation: heading-pop 1s cubic-bezier(0.68, -0.55, 0.27, 1.55);
}

.calc-heading:hover {
  letter-spacing: 6px;
  filter: drop-shadow(0 6px 24px #43e97bcc);
  text-shadow: 0 6px 24px #00c6ff99, 0 0px 16px #fff8;
  transform: scale(1.05) rotate(-1deg);
  animation: heading-glow 0.7s alternate infinite;
}

@keyframes heading-pop {
  0% {
    transform: scale(0.7) rotate(-8deg);
    opacity: 0;
  }
  80% {
    transform: scale(1.1) rotate(2deg);
    opacity: 1;
  }
  100% {
    transform: scale(1) rotate(0deg);
  }
}
@keyframes heading-glow {
  0% {
    text-shadow: 0 6px 24px #00c6ff99, 0 0px 16px #fff8;
  }
  100% {
    text-shadow: 0 12px 32px #43e97bcc, 0 0px 32px #fff;
  }
}
/* ...existing code... */
