可展开的 grid 布局

            
            :root {
  --move-duration: 0.3s;
}

button {
  appearance: none;
  border: none;
  font: inherit;
  color: inherit;
  letter-spacing: inherit;
  background: transparent;
}

body {
  height: 100vh;
  margin: 0;
  display: grid;
  place-items: center;
  background: linear-gradient(
    135deg,
    #FFF,
    #eed
  );
  font-size: 14px;
}

.icon {
  color: #7a8a90;
  transition: all .3s;
  display: block;
}

.container {
  --gutter: 1em;
  display: grid;
  grid-template-columns: 1fr 2fr;
  width: min(80%, 360px);
  padding: var(--gutter);
  gap: var(--gutter);
  background: #fff;
  border-radius: 2em;
  box-shadow: .1em .1em .3em rgba(0,0,0,0.2);
}

.region {
  --region-bg: #DAEEEEAA;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 1em;
  text-align: center;
  background: var(--region-bg);
  font-size: 1.1em;
  font-variant: small-caps;
  letter-spacing: .1em;
  color: #789599;
}

.header {
  height: min(5vh, 45px);
  grid-column: span 2;
  border-top-left-radius: 1em;
  border-top-right-radius: 1em;
}

.with-long-aside .header {
  grid-row: 1;
  grid-column: 2;
  border-top-left-radius: 0;
  animation: pulse linear forwards 0.5s;
}

@keyframes pulse {
  20% {
    background: lemonchiffon;
  }
  to {
    background: var(--region-bg);
  }
}

.header-label {
  display: flex;
  justify-content: flex-end;
  min-width: 1%;
  transition: all .5s;
}

.with-long-aside .header-label {
  animation:
    move-left-header-label
    var(--move-duration)
    forwards;
}

.without-long-aside .header-label {
  justify-content: flex-start;
  animation:
    move-right-header-label
    var(--move-duration)
    forwards;
}

@keyframes move-left-header-label {
  from {
    min-width: 85%;
  }
  to {
    min-width: 1%;
  }
}

@keyframes move-right-header-label {
  from {
    min-width: 52%;
  }
  to {
    min-width: 1%;
  }
}

.main {
  height: min(30vh, 225px);
}

.aside {
  position: relative;
  padding: 0;
}

.aside:hover {
  box-shadow: inset 0 0 5em .1em #0351;
}

.with-long-aside .aside {
  grid-row: 1 / 3;
  border-top-left-radius: 1em;
  animation: pulse linear forwards 0.5s;
}

.aside button {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 1em;
  text-align: center;
  width: 100%;
  height: 100%;
  cursor: pointer;
}

.aside-label {
  display: flex;
  align-items: flex-end;
  min-height: 1%;
  transition: all .5s;
}

.with-long-aside .aside-label {
  animation:
    move-up-aside-label
    var(--move-duration)
    forwards;
}

.without-long-aside .aside-label {
  align-items: flex-start;
  animation:
    move-down-aside-label
    var(--move-duration)
    forwards;
}

@keyframes move-up-aside-label {
  from {
    min-height: 32%;
  }
  to {
    min-height: 1%;
  }
}

@keyframes move-down-aside-label {
  from {
    min-height: 44%;
  }
  to {
    min-height: 1%;
  }
}

.aside-instructions {
  position: absolute;
  bottom: 1em;
  width: 100%;
  display: flex;
  justify-content: space-evenly;
  align-items: center;
  transition: all .3s;
}

@media (max-height: 400px) {
  .aside-instructions {
    display: none;
  }
}

.click-icon,
.chevron-icon,
.chevron-contour-icon {
  width: max(2.4vmin, 12px);
  height: max(2.4vmin, 12px);
  transition: all .2s;
}

.click-icon-container {
  position: relative;
}

:active .click-icon-container::after {
  content: "";
  position: absolute;
  top: -8px;
  left: 1.5px;
  display: block;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #a8c5c9;
  opacity: 0;
  transform: scale(0);
  animation: icon-click .5s forwards;
}

@keyframes icon-click {
  40% {
    opacity: 1;
  }
  to {
    transform: scale(1);
    opacity: 0;
  }
}

.click-icon {
  position: relative;
  z-index: 1;
}

.icon-separator {
  padding-left: 3px;
  font-size: .9em;
}

.chevron-icon-container {
  position: relative;
}

.with-long-aside .chevron-icon {
  transform: translateY(-10%)
}

.chevron-contour-icon {
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
  filter:
    contrast(2)
    brightness(1.25)
    hue-rotate(30deg);
}

.with-long-aside .chevron-contour-icon {
  transform: scale(.9) translateY(5%);
  opacity: 0.6;
}

.footer {
  height: min(5vh, 45px);
  grid-column: span 2;
  border-bottom-left-radius: 1em;
  border-bottom-right-radius: 1em;
}
        

            
            const container = document.querySelector('.container')
const target = document.querySelector('.aside button')

let initial = true

const toggle = () => {
  container.classList.toggle('with-long-aside')
  if (!initial) {
    container.classList.toggle('without-long-aside')
  }
  initial = false
}

const onKeyUp = (e) => {
  if (e.key === 'ArrowUp') {
    toggle()
  }
}

target.addEventListener('click', toggle)
window.addEventListener('keydown', onKeyUp)