styles.css

:root {
  /* COLORS */
  --container-color: #c5e4e7;
  --main-bg: #ffffff;
  --custom-input-bg: #f3f8fb;
  --active-green: #26c2ad;
  --hover-green: #9fe8df;
  --dark-green: #00474b;
  --sub-text: #5e7a7d;
  --btn-disabled: #0d686d;

  /* FONTS */
  --primary-font: "Space Mono", monospace;
}

*,
*::before,
*::after {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: var(--primary-font);
}

body {
  min-height: 100vh;
}

.container {
  padding-top: 3em;
  height: 100%;
  background-color: var(--container-color);
}

.svg {
  display: flex;
  justify-content: center;
  align-content: center;
}

#calculator {
  height: 85%;
  display: flex;
  flex-direction: column;
  margin-top: 3em;
  padding: 2em;
  border-radius: 25px 25px 0 0;
  background-color: var(--main-bg);
}

.input-panel > div {
  margin-bottom: 1em;
}

label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--sub-text);
  margin-bottom: 0.7em;
}

.select-tip,
.total-bill,
.number-of-people {
  display: flex;
  flex-direction: column;
}

#bill-amount {
  background-image: url(/images/icon-dollar.svg);
  background-repeat: no-repeat;
  background-position: 5% 50%;
}

#people-number {
  background-image: url(/images/icon-person.svg);
  background-repeat: no-repeat;
  background-position: 5% 50%;
}

#bill-amount,
#people-number {
  height: 50px;
  width: 100%;
  padding: 10px 10px 10px 50px;
  border-radius: 5px;
  border: none;
  background-color: var(--custom-input-bg);
  direction: rtl;
  font-weight: 600;
  font-size: 1.7rem;
  color: var(--dark-green);
  appearance: none;
}

#bill-amount:focus,
#people-number:focus {
  outline: none !important;
  border: 2px solid var(--active-green);
}

input::-webkit-outer-spin-button,
input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.btn-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  grid-template-rows: minmax(50px, 1fr) repeat(2, 1fr);
  gap: 15px;
}

.btn-grid button {
  background-color: var(--dark-green);
  border: none;
  border-radius: 5px;
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--main-bg);
  cursor: pointer;
}

.btn-grid button:hover {
  background-color: var(--active-green);
  color: var(--dark-green);
}

.btn-grid button:active {
  background-color: var(--active-green);
  color: var(--hover-green);
}

#custom {
  border: none;
  background-color: var(--custom-input-bg);
  direction: rtl;
  font-size: 1.7rem;
  color: var(--dark-green);
  font-weight: bold;
  padding: 10px;
  border-radius: 5px;
}

#custom:focus {
  outline: none !important;
  border: 2px solid var(--active-green);
}

#number-of-people {
  display: flex;
  justify-content: space-between;
}

.error-msg {
  color: red;
  opacity: 0;
}

.show-error-msg {
  transition: opacity 0.3s ease-in-out;
  opacity: 1;
}

.result-panel {
  display: flex;
  flex-direction: column;
  background-color: var(--dark-green);
  padding: 1.5em;
  border-radius: 12px;
  margin-top: 0.7em;
}

.total-per-person,
.tip-per-person {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1em;
}

.tip-label,
.total-label {
  color: var(--main-bg);
  font-weight: 600;
}

.sub-text {
  color: var(--sub-text);
  font-size: 0.7rem;
}

.total-amount,
.tip-amount {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--active-green);
}

#reset {
  cursor: pointer;
  padding: 0.7em;
  border: none;
  border-radius: 5px;
  font-size: 1.2rem;
  font-weight: 800;
  background-color: var(--active-green);
  color: var(--dark-green);
}

#reset:disabled {
  background-color: var(--btn-disabled);
}

#reset:hover {
  background-color: var(--hover-green);
}

.attribution {
  margin: 0 0 2em;
}

@media only screen and (min-width: 1485px) {
  body {
    background-color: var(--container-color);
  }

  .container {
    height: 100vh;
    padding: 3em 15em;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
  }

  #calculator {
    padding: 1.4em 2em;
    margin-top: 4em;
    width: 90%;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 70px;
    border-radius: 25px;
  }

  .btn-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-template-rows: minmax(50px, 1fr) repeat(1, 1fr);
    gap: 15px;
  }

  .btn-grid button:hover {
    background-color: var(--active-green);
    color: var(--dark-green);
  }

  .btn-grid button:active {
    background-color: var(--active-green);
    color: var(--dark-green);
  }

  .total-per-person {
    margin-top: 40px;
  }

  .input-panel {
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
  }

  .result-panel {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
  }

  .sum-total {
    margin-top: 1em;
  }

  .total-amount,
  .tip-amount {
    font-size: 3rem;
  }

  .tip-label,
  .total-label {
    font-size: 1.3rem;
    font-weight: 600;
  }

  .sub-text {
    font-size: 1rem;
  }

  .attribution {
    font-size: 1rem;
  }
}