Simple layout

by Julien Roche

HTML

<body class="app">
  <main class="app__content">
    <section class="app__content__grid app-section">A</section>
    <section class="app__content__grid app-section">B</section>
    <section class="app__content__grid app-section">C</section>
  </main>
  <footer class="app__footer app-section">G</footer>
</body>

CSS

html,
body {
  border: none;
  height: 100%;
  margin: 0 0 0 0;
  padding: 0 0 0 0;
  width: 100%;
}

.app {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.app__content {
  display: grid;
  flex: 1;
  grid-gap: 0.5rem;
  grid-template-columns: repeat(3, 1fr);
  margin: 0.5rem 1rem;
}

.app__content__grid {
}

.app__footer {
  flex: 1;
  margin: 0 1rem 0.5rem 1rem;
}

.app-section {
  border: 1px solid black;
  border-radius: 0.5rem;
  overflow: hidden;
  padding: 0.5rem;
}