/* -- All about this -- */
.content-box {
  box-sizing: content-box;
}

.border-box {
  box-sizing: border-box;
}
/* ------------------- */

/* Just use this rule and you'll get a predictable sizes behavior */
*,
::before,
::after {
  box-sizing: border-box;
}

:root {
  --width: 300;
  --padding: 40;
  --border-width: 10;
  --bg-color: #f5f5f5;
  --padding-color: #b9dfa7;
  --border-color: #ffe5bd;
  --content-color: #9bb4f3;
  --light-text-color: #989898;
  --highlighted-color: #8f00ff;
}

body {
  min-width: 320px;
  width: 100%;
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, Segoe UI, Helvetica, Arial, sans-serif;
  line-height: 1.5;
  color: #222;
}

p {
  margin: 0;
}

[data-thin] {
  font-weight: 100;
}

[data-medium] {
  font-weight: 500;
}

[data-monospace] {
  font-family: Menlo, monospace;
}

[data-light-text] {
  color: var(--light-text-color);
}

[data-highlighted] {
  color: var(--highlighted-color);
}

.main {
  display: grid;
  grid-template-areas:  'title title'
                        'input input'
                        'box-c box-b';
  grid-template-columns: 1fr 1fr;
  grid-auto-flow: column;
  gap: 40px;
  max-width: 1200px;
  margin-right: auto;
  margin-left: auto;
  padding: 30px 24px 50px;
}

.heading {
  grid-column: 1/-1;
  max-width: calc(100vw - 30px);
}

.heading-title {
  margin-top: 32px;
  margin-bottom: 30px;
  font-size: 36px;
  letter-spacing: .5px;
}

fieldset {
  grid-area: input;
  margin: 0;
  padding: 0;
  border: none;
}

.user-input {
  display: flex;
  flex-wrap: wrap;
  margin-top: 20px;
}

.input-wrapper {
  display: flex;
  align-items: center;
  margin-right: 50px;
}

.input-wrapper label::before {
  content: '';
  position: relative;
  top: 4px;
  display: inline-block;
  width: 20px;
  height: 20px;
  margin-right: 8px;
  border-radius: 50%;
}

[for='width-input']::before {
  background-color: var(--content-color);
  background-image: conic-gradient(var(--border-color) 33%, var(--content-color) 0 66%, var(--padding-color) 0);
}

[for='border-input']::before {
  background-color: var(--border-color);
}

[for='padding-input']::before {
  background-color: var(--padding-color);
}

.input-wrapper input,
.input-wrapper span {
  margin-left: 10px;
}

.input-wrapper input {
  width: 60px;
  padding: 5px 0 5px 10px;
  font-family: inherit;
  font-size: inherit;
  border: 1px solid var(--light-text-color);
  border-radius: 2px;
}

.container-title {
  font-size: inherit;
}

.box-wrapper {
  padding: 40px 20px 140px;
  background-color: var(--bg-color);
}

.box {
  position: relative;
  width: calc(var(--width) * 1px);
  margin: auto;
  padding: calc(var(--padding) * 1px);
  background-color: var(--padding-color);
  border: calc(var(--border-width) * 1px) solid var(--border-color);
  transition: all .25s;
}

.content {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 100px;
  padding-top: 15px;
  padding-bottom: 15px;
  text-align: center;
  font-size: 12px;
  background-color: var(--content-color);
}

.content-width {
  font-size: 16px;
  line-height: 2;
}

.description {
  position: absolute;
  top: calc(var(--border-width) * 1px + 100% + 20px);
  left: calc(var(--border-width) * -1px);
  font-size: 12px;
  line-height: 2;
  transition: all .25s;
}

.description p {
  white-space: pre;
}

@media (max-width: 900px) {
  .main {
    grid-template-areas:  'title'
                          'input'
                          'box-c'
                          'box-b';
    grid-template-columns: 1fr;
    column-gap: 0;
  }

  .heading-title {
    margin-top: 0;
    margin-bottom: 15px;
  }

  .user-input {
    flex-direction: column;
    width: 290px;
    margin-top: 0;
  }
  
  .input-wrapper {
    margin-right: 0;
  }

  .input-wrapper + .input-wrapper {
    margin-top: 16px;
  }

  .input-wrapper input {
    width: 80px;
    margin-left: auto;
  }

  .box-wrapper {
    padding: 0 0 85px;
    background-color: #fff;
  }

  .box {
    margin: 0;
  }
}

@media (max-width: 375px) {
  .main {
    padding-right: 15px;
    padding-left: 15px;
  }

  .box-wrapper {
    padding-bottom: 100px;
  }

  .description p {
    width: calc(100vw - 30px);
    white-space: normal;
  }
}