/* ===============================
   🧮 Casio-Style Calculator Styles
=============================== */


.calculator-container {
  background: #e6e6e6;
  padding: 20px;
  align-items: center;
  text-align: center;
  border-radius: 15px;
  width: 320px;
  box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.section-title, .section-subtitle {
  text-align: center;
}

.section-title {
  margin-bottom: 5px;
  font-size: 1.6rem;
}

.section-subtitle {
  margin-bottom: 20px;
  font-size: 0.95rem;
  color: #555;
}

.calc-display input {
  width: 100%;
  height: 60px;
  font-size: 1.8rem;
  text-align: right;
  border-radius: 10px;
  border: 1px solid #aaa;
  margin-bottom: 15px;
  padding-right: 10px;
  background-color: #fff;
}

.calc-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.btn {
  padding: 18px 0;
  font-size: 1.2rem;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: transform 0.1s ease, background 0.2s ease;
}

.btn:active {
  transform: translateY(2px);
}

/* Number buttons */
.num {
  background-color: #fff;
  color: #000;
}

.num.zero {
  grid-column: span 2;
}

/* Operator buttons */
.op {
  background-color: #f9a825;
  color: #fff;
}

.op:hover {
  background-color: #f57f17;
}

/* Action buttons */
.action {
  background-color: #e57373;
  color: #fff;
}

.action:hover {
  background-color: #d32f2f;
}

/* Equal button */
.equal {
  background-color: #64b5f6;
  color: #fff;
  grid-row: span 2;
}

.equal:hover {
  background-color: #1976d2;
}