<div class="info">Recommended: use latest browser or use <b>firefox developer browser</b></div>
<div class="parent">
  <div class="child">child😊</div>
  <div class="child">child😉</div>
  <div class="child">child🤗</div>
</div>
I can't join with them🥺
@import url("https://fonts.googleapis.com/css2?family=Raleway:wght@100;200;300;400;500;600&display=swap");

:root {
  --black-color: #000;
  --white-color: #fff;
  --gray-color: gray;
  --info-background: #585954;
}

* {
  box-sizing: border-box;
  font-family: "Raleway", sans-serif;
  font-size: 1.5rem;
  background: var(--black-color);
  color: var(--white-color);
}

.parent {
  /* layout styling */
  display: flex; /* change to display: block flex */

  /*   common styling */
  width: 80%;
  max-width: 1200;
  margin: 5rem auto 0;
}

.child {
  /*   layout styling */
  flex-grow: 1;

  /*  common styling */
  outline: 5px solid var(--gray-color);
  background: var(--white-color);
  color: var(--black-color);
  padding: 1em;
  font-weight: bold;
  text-align: center;
}
/* info styling */
.info {
  background: var(--info-background);
  padding: 1em 0.5em;
  max-width: 1200px;
  text-align: center;
}

@media (max-width: 600px) {
  * {
    font-size: 1.2rem;
  }
}
@media (max-width: 400px) {
  * {
    font-size: 1rem;
  }
}

External CSS

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External JavaScript

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