accordion-item.css

:root {
  --brand-main: #0e688b;
  --brand-main-light: #107eab;
  --brand-main-active: #005379;
  --brand-main-dark: #003146;
  --brand-main-nearly-black: #000222;
  --grayscale-white: #fff;
  --grayscale-light: #f8f8f8;
  --grayscale-medium: #d2d2d2;
  --grayscale-medium-dark: #979797;
  --grayscale-dark: #555555;
  --grayscale-black: #000000;
  --additional-red-light: #E5053A;
  --additional-red-dark: #A31621;
  --additional-purple-light: #420039;
  --additional-yellow: #F9A21A;
  --additional-skyblue: #48C5F8;
  --additional-orange: #D14600;
  --additional-green-light: #96BA3C;
  --additional-green-dark: #006400;
}

* {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

:root {
  --breakpoint-narrow: 30rem;
  --breakpoint-medium: 768px;
  --breakpoint-wide: 60rem;
  --breakpoint-extrawide: 75rem;
  --breakpoint-max-width: 75rem;
  --breakpoint-overwide: 80rem;
}

:host {
  display: block;
}

.hy-accordion__item {
  margin-bottom: 1rem;
  -webkit-transition: all 0.25s ease-in-out;
  transition: all 0.25s ease-in-out;
}

.hy-accordion__item__is-open {
  background: linear-gradient(to bottom, var(--grayscale-dark) 2px, transparent 2px, transparent calc(100% - 2px), var(--grayscale-dark) calc(100% - 2px)) no-repeat, linear-gradient(to left, var(--grayscale-dark) 2px, transparent 2px, transparent calc(100% - 2px), var(--grayscale-dark) calc(100% - 2px)) no-repeat;
  background-position: center;
  background-size: calc(100% - .5rem) 100%, 100% calc(100% - .5rem);
  margin-left: -1rem;
  margin-right: -1rem;
  -webkit-transition: all 0.25s ease-in-out;
  transition: all 0.25s ease-in-out;
}

@media (min-width: 48em) {
  .hy-accordion__item__is-open {
    margin-left: -2rem;
    margin-right: -2rem;
  }
}

.hy-accordion__item__is-open .hy-accordion--heading {
  margin: 0 auto;
  width: calc(100% - 2.25rem);
  -webkit-transition: all 0.25s ease-in-out;
  transition: all 0.25s ease-in-out;
}

@media (min-width: 48em) {
  .hy-accordion__item__is-open .hy-accordion--heading {
    width: calc(100% - 4.25rem);
  }
}

.hy-accordion__item__is-open .hy-accordion--heading .hy-accordion--heading__icon {
  -webkit-transform: rotateX(180deg);
  transform: rotateX(180deg);
}

.hy-accordion--heading {
  -webkit-box-pack: start;
  -ms-flex-pack: start;
  justify-content: flex-start;
  letter-spacing: -0.69px;
  line-height: 28px;
  margin: 0 auto;
  -webkit-transition: all 0.25s ease-in-out;
  transition: all 0.25s ease-in-out;
  width: 100%;
}

.hy-accordion--heading .hy-accordion__button {
  background: linear-gradient(to bottom, var(--grayscale-dark) 1px, transparent 1px, transparent calc(100% - 1px), var(--grayscale-dark) calc(100% - 1px)) no-repeat, linear-gradient(to left, var(--grayscale-dark) 1px, transparent 1px, transparent calc(100% - 1px), var(--grayscale-dark) calc(100% - 1px)) no-repeat;
  background-position: center;
  background-size: calc(100% - .5rem) 100%, 100% calc(100% - .5rem);
  color: var(--brand-main-nearly-black);
  -webkit-box-orient: horizontal;
  -webkit-box-direction: normal;
  -ms-flex-direction: row;
  flex-direction: row;
  font-family: var(--main-font-family);
  font-size: 22px;
  font-weight: 600;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  border: none;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  height: 100%;
  -webkit-box-pack: start;
  -ms-flex-pack: start;
  justify-content: flex-start;
  padding: 0.75rem 1.75rem 0.75rem 1.25rem;
  width: 100%;
  -webkit-transition: all 0.35s ease-in;
  transition: all 0.35s ease-in;
}

@media (min-width: 48em) {
  .hy-accordion--heading .hy-accordion__button {
    font-size: 26px;
    letter-spacing: -0.82px;
    line-height: 32px;
  }
}

.hy-accordion--heading .hy-accordion__button[aria-expanded=true] {
  background: none;
  border-top: 0;
  border-left: 0;
  border-right: 0;
  border-bottom: 1px solid var(--grayscale-medium-dark);
  padding: 0.85rem 1rem 1rem 1rem;
  -webkit-transition: all 0.35s ease-in;
  transition: all 0.35s ease-in;
}

.hy-accordion--heading .hy-accordion--heading__icon {
  margin-right: 0.95rem;
}

.hy-accordion--heading .hy-accordion--heading__icon svg {
  fill: var(--brand-main);
}

.hy-accordion__content {
  display: block;
  height: 0;
  padding: 0;
  overflow: hidden;
  -webkit-transition: all 0.25s ease-in-out;
  transition: all 0.25s ease-in-out;
}

.hy-accordion__content--inner-wrapper {
  display: block;
  padding: 1rem 5% 1.25rem !important;
}