*{
  margin: 0; padding: 0; box-sizing: border-box;
}

body {
  background-color: #CEC;
  color: #234;
  font-family: verdana;
}

h1 {
  text-align: center;
  margin: 8px 0;
  border-bottom: 2px solid #234;
  padding-bottom: 8px;
}

h2 {
  margin: 8px; 
  font-weight: normal;
  background-color: #234;
  color: #CEC;
  padding: 4px; 
}

.flex-parent {
  border: 4px transparent;
  min-height: 100px;
  display: flex;
  margin: 8px 8px 40px 8px;
}

.flex-child {
  border: 4px solid green;
  min-height: 80px;
  margin: 8px;
  flex-grow: 1;
  text-align: center;
  font-weight: bold;
}

.demo2 .flex-parent {
  border: 4px transparent;
  justify-content: space-around;
}

.demo2 .flex-child {
  border: 4px solid black;
  flex-grow: 0;
  min-width: 16px;
}

.demo3 .flex-parent {
  justify-content: space-between;
  border: 4px transparent;
}

.demo3 .flex-child {
  flex-grow: 0;
  min-width: 16px;
  border: 4px solid black;
}

.demo4 .flex-parent {
  justify-content: space-evenly;
  border: 4px transparent;
}

.demo4 .flex-child {
  flex-grow: 0;
  min-width: 16px;
  border: 4px solid black;
}

.demo5 .flex-parent,
.demo6 .flex-parent {
  border: 4px solid red;
}

.demo5 .flex-parent {
  flex-direction: row-reverse;
}

.demo5 .flex-child:last-child {
  background-color: yellow;
}

.demo6 .flex-parent {
  flex-wrap: wrap;
}

.demo6 .flex-child {
  background-color: pink;
  min-width: 300px; 
  flex-grow: 1;
}

.demo7 .flex-parent {
  border: 4px transparent;
  min-height: 200px;
  justify-content: center;
}

.demo7 .flex-child {
  flex-grow: 0;
}

.demo7 .flex-child:last-child {
  background-color: yellow;
  max-height: 100px;
  min-width: 100px; aspect-ratio: 1;
  align-self: center;
}

.demo8 .flex-parent {
  border: 4px solid red;
  flex-flow: row wrap;
  justify-content: center;
  gap: 10px;
}

.demo8 .flex-child {
  flex-basis: 25%;
  margin: 0;
  flex-grow: 1;
}