html,
body {
  margin: auto;
  padding: 0;
  font-family: monospace;
  font-size: 13px;
  color: rgba(0,0,0);
  background-attachment: fixed;
  background-position: center;
  background-color: rgba(255,235,225);
  max-width: 500px;
  margin-bottom: 1rem;
  margin-top: 1rem;
}

mark {
  background-color: #FDFCCA;
}

header {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

aside {
  font-size: 1rem;
}

nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2.5rem;
    margin-top: 0rem;
    margin-bottom: 0rem;
}

.flag-img {
    float: right;
    width: 50px;
    max-width: 15%;
    margin: 0 0 1rem 1rem;
}

.software-list {
    font-size: 1rem;
}

.post-list {
    font-size: 1rem;
}

.container {
    max-width: 500px;
    margin: auto;
    padding: 0rem;
}

h4 {
    font-size: 1rem;
    margin-top: 1rem;
}

p {
    margin-bottom: 1rem;
    margin-top: 2rem;
}

<style>
  table {
    margin-top: 2rem;
    margin-bottom: 1rem;
    border-spacing: 10px;
    border-collapse: collapse;
    width:100%;
  }

  td, th {
    padding: 10px;
    border: 6px double grey;
    background-color: rgba(255, 221,170);
  }

  button.active {
      background: #999999;
      color: white;
  }
</style>