body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, sans-serif;
  background-color: #f1f5f9;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  padding: 20px;
}

.calculator {
  width: 100%;
  max-width: 400px;
  background-color: #1e293b;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1),
    0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.display {
  background-color: #0f172a;
  padding: 20px;
  text-align: right;
}

.previous-operand {
  color: #94a3b8;
  font-size: 16px;
  min-height: 24px;
  margin-bottom: 8px;
  word-wrap: break-word;
  word-break: break-all;
}

.current-operand {
  color: #f8fafc;
  font-size: 36px;
  font-weight: 600;
  min-height: 48px;
  word-wrap: break-word;
  word-break: break-all;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background-color: #334155;
}

button {
  border: none;
  outline: none;
  font-size: 18px;
  padding: 20px;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
  display: flex;
  justify-content: center;
  align-items: center;
}

button:active {
  transform: scale(0.97);
}

.number,
.decimal {
  background-color: #1e293b;
  color: #f8fafc;
}

.number:hover,
.decimal:hover {
  background-color: #334155;
}

.operation {
  background-color: #0f172a;
  color: #38bdf8;
  font-weight: bold;
}

.operation:hover {
  background-color: #1e293b;
}

.equals {
  background-color: #0369a1;
  color: #f8fafc;
  font-weight: bold;
}

.equals:hover {
  background-color: #0284c7;
}

.clear,
.delete,
.function {
  background-color: #475569;
  color: #f8fafc;
}

.clear:hover,
.delete:hover,
.function:hover {
  background-color: #64748b;
}

.settings-panel {
  background-color: #0f172a;
  padding: 10px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid #334155;
}

.precision-control {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #94a3b8;
  font-size: 14px;
}

input[type="number"] {
  background-color: #1e293b;
  border: 1px solid #334155;
  border-radius: 4px;
  color: #f8fafc;
  padding: 4px 8px;
  width: 60px;
  font-size: 14px;
}

.angle-mode {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #94a3b8;
  font-size: 14px;
}

select {
  background-color: #1e293b;
  border: 1px solid #334155;
  border-radius: 4px;
  color: #f8fafc;
  padding: 4px 8px;
  font-size: 14px;
}

.advanced-functions {
  display: none;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background-color: #334155;
}

.toggle-advanced {
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #0f172a;
  color: #38bdf8;
  padding: 10px;
  font-size: 14px;
  cursor: pointer;
}

.toggle-advanced:hover {
  background-color: #1e293b;
}

.error {
  color: #ef4444;
}

.memory-indicator {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: #38bdf8;
  margin-right: 8px;
  opacity: 0;
  transition: opacity 0.3s;
}

.memory-active {
  opacity: 1;
}