@import url("https://fonts.googleapis.com/css2?family=Montserrat&display=swap");

* {
  margin: 0;
  padding: 0;
}

:root {
  --primary-color: #111827;
  --secondary-color: #d1d5db;
  --white-color: #fff;
}

body {
  line-height: 2;
  font-family: "Montserrat", sans-serif;
  font-size: 1.2rem;
}

.main-heading {
  text-align: center;
}

.container {
  display: flex;
  flex-direction: column;
  padding: 2rem;
  width: 50vw;
  background-color: var(--secondary-color);
  color: var(--primary-color);
  margin: auto;
}

#bill-amount,
#cash-given {
  width: 12vw;
  height: 3vh;
  padding: 0.5rem;
  border: 0 solid var(--white-color);
}

label {
  font-weight: bold;
}

#calculate {
  background-color: var(--primary-color);
  color: var(--white-color);
  width: 10rem;
  font-size: 1.2rem;
  padding: 0.5rem 1rem;
  margin: 1rem 0 0 0;
  border-radius: 0.5rem;
  border: 1px solid var(--white-color);
}

caption {
  font-weight: bold;
  font-size: 1.5rem;
}

table,
th,
td {
  border: 1px solid var(--primary-color);
  border-collapse: collapse;
}

th,
td {
  padding: 0.5rem;
  text-align: center;
  background-color: #e5e7eb;
}

th {
  font-weight: bold;
}