*, *::before, *::after {
  box-sizing: border-box;
}

:root {
  --color-primary: #ee5252;
  --color-body: #333;
  --color-background: #ddd;
}

body {
  font-family: system-ui, sans-serif;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 1.125rem;
  line-height: 1.6;
  color: var(--color-body);
  background: var(--color-background);
}

.content {
  background: white;
  width: 70vw;
  padding: 3em;
  box-shadow: 0 0 3em rgba(0, 0, 0, 0.15);
  position: relative;
}

.search-bar {
  --size: 60px;
  border: 2px solid var(--color-primary);
  display: flex;
  align-items: stretch;
  border-radius: 100vh;
  height: var(--size);
  width: var(--size);
  padding: 3px;
  position: relative;
  transition: width 250ms cubic-bezier(0.2, 0.9, 0.3, 1.1);
  overflow: hidden;
}

.search-bar__input {
  flex-grow: 1;
  font-size: 1.5rem;
  padding: 0 1em;
  border: none;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  opacity: 0;
  cursor: pointer;
}

.search-bar__input:focus {
  outline: 0;
}

.search-bar__submit {
  font-size: 1.5rem;
  cursor: pointer;
  border: none;
  border-radius: 50%;
  width: calc(var(--size) - 10px);
  height: calc(var(--size) - 10px);
  margin-left: auto;
  background-color: transparent;
  color: var(--color-primary);
  transition: background-color 250ms ease-in-out;
}

.search-bar:focus-within {
  width: 100%;
}

.search-bar:focus-within .search-bar__submit {
  background-color: var(--color-primary);
  color: white;
}

.search-bar:focus-within .search-bar__submit:focus,
.search-bar:focus-within .search-bar__submit:hover {
  outline: 0;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
}

.search-bar:focus-within .search-bar__input {
  opacity: 1;
  cursor: initial;
  width: calc(100% - var(--size));
}