<main>
  <form>
    <div class="form-header">
      <h1 class="form-header__title">Personal info</h1>
      <p class="form-header__progress">Step 2 of 4</p>
    </div>

    <fieldset class="mailing">
      <legend class="mailing__title">Mailing Address</legend>
        <label for="name">
          Name
          <input required id="name" name="name" autocomplete="name" autocorrect="off" type="text" />
        </label>
        <label for="street-address">
          Street Address
          <input required id="street-address" name="street-address" autocomplete="street-address" autocorrect="off" type="text" />
        </label>
        <label for="address-line1">
          Apartment <span class="optional">optional</span>
          <input id="address-line1" name="address-line1" autocomplete="address-line1" autocorrect="off" type="text" />
        </label>
        <label for="city">
          City
          <input required novalidate="" id="city" name="city" autocomplete="shipping locality" autocapitalize="on" autocorrect="off" type="text" />
        </label>
        <label for="postal-code">
          Postal Code
          <input required novalidate="" id="postal-code" name="postal-code" autocomplete="postal-code" autocorrect="off" type="number" />
        </label>

        <label for="delivery-instructions">
          Delivery Instructions <span class="optional">optional</span>
          <textarea id="delivery-instructions" name="textarea" dir="auto"></textarea>
        </label>
    </fieldset>

    <input name="submit" type="submit" value="Save and continue" />
  </form>
</main>

// Scale the form's size slightly when its input is focused.
// If `:focus-within` is not supported, form functionality is unaffected.
form:focus-within {
  box-shadow: 0px 0.2em 2.5em #c4c4c4;
  transform: scale(1.025); 
  
  // Remove the scaling for those who don't want animation.
  @media screen and (prefers-reduced-motion: reduce) {
    box-shadow: none;
    transform: none; 
  }
}


// Sass logic
$border: (
  radius: 0.25em,
  thickness: 1px
);

$color: (
  blue: #2491eb,
  gray-light: #f8f8f8,
  gray-medium: #e0e0e0,
  gray-dark: #444444,
  white: #ffffff
);

$font: (
  face-primary: "Open Sans",
  weight-light: 300
);

$transition: (
  easing: ease-out,
  speed-slow: 250ms,
  speed-fast: 125ms
);


// Form styling
body {
  background-color: map-get($color, gray-light);
  color: map-get($color, gray-dark);
  font-family: map-get($font, face-primary);
  padding-bottom: 6em;
}

main {
  margin: 1.5em;
  
  // Media Queries
  @media screen and (min-width: 35em) {
    margin: 3em;
  }
}

form {
  background-color: map-get($color, white);
  border-top: map-get($border, thickness) solid map-get($color, blue);
  border-right: map-get($border, thickness) solid map-get($color, gray-medium);
  border-bottom: map-get($border, thickness) solid map-get($color, gray-medium);
  border-left: map-get($border, thickness) solid map-get($color, gray-medium);
  box-shadow: 0px 1px 1px #aaaaaa;
  display: block;
  max-width: 90vw;
  margin: 0 auto;
  padding: 3em 1.5em 0.5em 1.5em;
  transition: 
    map-get($transition, speed-slow) box-shadow map-get($transition, easing),
    map-get($transition, speed-slow) transform map-get($transition, easing);
  
  // Media Queries
  @media screen and (min-width: 35em) {
    max-width: 70vw;
    padding: 3em 2em 0.5em 2em;
  }
}

.form-header {
  border-bottom: map-get($border, thickness) solid map-get($color, gray-medium);
  display: flex;
  flex-direction: column;
  margin-bottom: 2em;
  padding-bottom: 0.75em;
  width: 100%;
  
  // Media Queries
  @media screen and (min-width: 26em) {
    align-items: flex-end;
    justify-content: space-between;
    flex-direction: row;
  }
  
  &__title {
    font-weight: map-get($font, weight-light);
    margin: 0 0 0.5em 0;
    padding: 0;
    
    // Media Queries
    @media screen and (min-width: 26em) {
      margin: 0;
    }
  }
  
  &__progress {
    font-size: 0.85em;
    letter-spacing: 0.05em;
    margin: 0;
    padding: 0 0.25em 0.25em 0;
    text-transform: uppercase;
  }
}

.mailing {
  border: none;
  margin-bottom: 2em;
  padding: 0;
  
  &__title {
    font-size: 1.25em;
    font-weight: map-get($font, weight-light);
    margin-bottom: 1.5em;
    width: 100%;
  }
  
  .optional {
    font-variant: small-caps;
    letter-spacing: 0.025em;
    margin-left: 0.5em;
  }
}

label {
  cursor: pointer;
  display: block;
  transition: map-get($transition, speed-fast) color map-get($transition, easing);
  
  &:focus-within {
    color: map-get($color, blue);
  }
}

input[type="email"],
input[type="text"],
input[type="number"],
textarea {
  appearance: none;
  border: map-get($border, thickness) solid map-get($color, gray-medium);
  border-bottom-color: map-get($color, gray-dark);
  border-radius: 0;
  display: block;
  line-height: 1;
  margin-top: 0.5em;
  margin-bottom: 1.5em;
  padding: 0.85em 0.75em 0.75em 0.75em;
  width: calc(100% - 1.25em);
  transition: map-get($transition, speed-fast) border-color map-get($transition, easing);
  
  // States
  &:hover {
    border-color: map-get($color, gray-dark);
  }

  &:focus {
    border-color: map-get($color, blue);
    outline: map-get($border, thickness) solid map-get($color, blue);
  }
}

textarea {
  line-height: 1.5;
  margin-bottom: 0.5em;
  min-height: 4em;
  overflow: auto;
  resize: vertical;
}

input[type="submit"] {
  background-color: map-get($color, blue);
  border-radius: map-get($border, radius);
  border: map-get($border, thickness) solid darken(map-get($color, blue), 10%);
  color: map-get($color, white);
  font-size: 1.1em;
  letter-spacing: 0.025em;
  margin-top: 0.25em;
  margin-bottom: 2em;
  padding: 1em;
  transition: 
    map-get($transition, speed-fast) background-color map-get($transition, easing),
    map-get($transition, speed-fast) border-color map-get($transition, easing);
  width: 100%;  
  
  // States
  &:focus {
    box-shadow:
     0 0 0 3px map-get($color, white),
     0 0 0 6px map-get($color, blue);
    outline: none;
  }

  &:hover {
    background-color: darken(map-get($color, blue), 7%);
    border-color: darken(map-get($color, blue), 14%);
    text-decoration: underline;
  }
  
  &:active {
    background-color: darken(map-get($color, blue), 21%);
    border-color: darken(map-get($color, blue), 28%);
    position: relative;
     top: 1px;
    text-decoration: none;
    transition: none;
  }
}