rainyday.dev/freecodcamp/build-a-portfolio-page/styles.css

:root {
    --black: #222831;
    --grey: #393e46;
    --blue: #0092ca;
    --white: #eeeeee;
  }
  
  *, ::before, ::after {
    margin: 0;
    padding: 0;
  }
  
  body {
    box-sizing: border-box;
    height: 100vh;
    width: 100%;
    color: var(--white);
  }
  
  html {
    font-size: 16px;
  }
  
  a {
    text-decoration: none;
    color: var(--white);
  }
  
  a:hover {
    text-decoration: underline;
  }
  
  header {
    padding: 0.5rem;
    display: flex;
    align-items: center;justify-content: space-between;
    width: 100%;
    position: fixed;
    top: 0;
    background-color: var(--black);
  }
  header p {
    padding: 0.25rem;
  }
  navbar {
    padding-right:1rem;
  }
  
  navbar a {
    padding: 0.25rem;
  }
  
  #welcome-section {
    padding: 3rem;
    height: 100vh;
    background-color: var(--blue);
  }
  
  h1 {
    padding: 1rem;
    text-align: center;
  }
  
  #welcome-section p {
    line-height: 1.25rem;
    padding: 1.1rem;
  }
  
  #projects {
    height: 75vh;
    padding: 1rem;
    padding-top: 0.5rem;
    background-color: var(--grey);
  }
  
  #projects h2 {
    text-align: center;
    padding: 0.5rem;
  }
  
  .project-tile {
    display: flex;
    flex-direction: column;
    width: 45vw;
    height: auto;
    padding: 1rem;
    border: 1px solid var(--blue);
    border-radius: 10px;
  }
  
  .project-tile img {
    max-height: 100%;
    width: auto;
    border-radius: 10px;
    padding-bottom: 0.5rem;
  }
  
  .project-tile p {
    padding-bottom: 0.5rem;
  }
  
  #contact {
    height: 30vh;
    padding: 1rem;padding-top: 0.5rem;background-color: var(--blue);
  }
  
  #contact h2 {
    padding: 0.5rem;
  }
  
  #contact ul {
  list-style-type: none;
    padding: 0.5rem;
  }
  
  #contact li {
    padding: 0.25rem;
  }
  
  @media only screen and (max-width: 768px) {
  
    #welcome-section {
      text-align: center;
    }
    
    #projects {
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    
    #contact {
      text-align: center;
    }
  }