input[type='number']::-webkit-outer-spin-button,
input[type='number']::-webkit-inner-spin-button {
  -webkit-appearance: none;
}

input[type='number'] {
  -moz-appearance: textfield;
  background-color: hsl(189, 41%, 97%);
  border: 1px solid transparent;
  border-radius: 5px;
  box-sizing: border-box;
  color: hsl(183, 100%, 15%);
  font-size: 24px;
  font-weight: bold;
  padding: 8px 18px;
  text-align: right;
  width: 100%;
}

input[type='number']:focus {
  border:  1px solid #10B981;
  background-image:none;
  -webkit-box-shadow: none;
  -moz-box-shadow: none;
  box-shadow: none;
  outline: none;
}

button {
  background-color: hsl(183, 100%, 15%);
  border: 1px solid transparent;
  border-radius: 8px;
  color: hsl(0, 0%, 100%);
  font-size: 24px;
  font-weight: bold;
  padding: 8px;
}

button:hover {
  background-color: hsl(185, 41%, 84%);
  color: hsl(183, 100%, 15%);
}

button.selected {
  background-color: hsl(172, 67%, 45%);
  color: hsl(183, 100%, 15%); 
}

body {
  background-color: hsl(185, 41%, 84%);
  font-family: Space Mono;
  font-size: 16px;
  margin: 0;
}


header {
  color: hsl(183, 100%, 15%);
  display: grid;
  font-weight: bold;
  gap: 5px;
  grid-template-columns: repeat(4, 1fr);
  margin: 30px auto;
  width: max-content;
}

main {
  background-color: hsl(0, 0%, 100%);
  border-radius: 20px;
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr;
  margin: auto;
  max-width: 900px;
  padding: 20px;
}

form {
  display: grid;
  gap: 30px;
}

form label {
  color: hsl(186, 14%, 43%);
  display: block;
  font-weight: bold;
  margin-bottom: 4px;
}

form .tip label {
  margin-bottom: 15px;
}

form .tip .options {
  display: grid;
  gap: 15px;
  grid-template-columns: repeat(2, 1fr);
}

.result {
  background-color: hsl(183, 100%, 15%);
  border-radius: 15px;
  color: hsl(0, 0%, 100%);
  display: flex;
  flex-direction: column;
  padding: 30px 20px;
}

.result-info {
  flex-grow: 1;
}

.result-info > div {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin-bottom: 30px;
}

.result-info > div > span:nth-child(2) {
  color: hsl(172, 67%, 45%);
  font-size: 36px;
  font-weight: bold;
  grid-row: span 2 / span 2;
  text-align: right;
}

.result-info > div > span:nth-child(3) {
  color: hsl(184, 14%, 56%);
}

.btn-reset {
  background-color: hsl(172, 67%, 45%);
  color: hsl(183, 100%, 15%);
  width: 100%;
}


.attribution { font-size: 11px; text-align: center; }
.attribution a { color: hsl(228, 45%, 44%); }


@media only screen and (min-width: 900px) {

  form .tip .options {
    grid-template-columns: repeat(3, 1fr);
  }
  
  form .people {
    margin-bottom: 0;
  }

  main {
    grid-template-columns: 1fr 1fr;
  }
}


/**
 * UTILITY
 */

.relative {
  position: relative;
}

.icon {
  position: absolute;
  top: 18px;
  left: 18px;
}