base.css

/******** CSS file from arp242/hello-css ********/

/*** Variables ***/
:root {
    --width-body:   54rem;   /* Width of main body text. */
    --pad-x:        4rem;    /* Padding to the side of the body. */
    --pad-y:        1rem;    /* Padding to the top and bottom of the body. */
    --color-bg:     #fbfbf7;    /* Background colour of main body text. */
    --color-text:   #252525; /* Colour of main body text. */
    --color-border: #aaa;    /* Border colour for table, fieldset, input. */
  
    --font: 18px/160% Calibri, 'DejaVu Sans Serif', sans-serif;
  
    /* Padding for full-width pre, table, and figure (.full class); needs to be a
     * variable here since we can't use variables inside media queries. */
    --full-margin-left: calc(-1 * var(--pad-x));
    --full-width: calc(100% + calc(var(--pad-x) * 2));
  }
  
  /* Properties for screens that are narrower than the body width. */
  @media (max-width: 54rem) {
    :root {
      --font: 14px/160% Calibri, 'DejaVu Sans Serif', sans-serif;
  
      --pad-x: 1rem;    /* Modest amount of padding to prevent wasting screen space. */
      --pad-y: .5rem;
    }
  }
  
  /* Even smaller screens, mostly mobile phones. */
  @media (max-width: 26rem) {
    :root {
      --font: 14px/140% Calibri, 'DejaVu Sans Serif', sans-serif;
    }
  }

  html {
    font: var(--font);
  
            text-size-adjust: none;      /* Disables text adjustment algorithm on some mobile browsers, this is */
    -webkit-text-size-adjust: none;      /* intended for sites that are not designed for mobile viewing. */
  }
  
  h1, h2, h3, h4, h5, h6 {
    /* Enable ligatures, works well with Libre Baskerville, which adds
     * (old-fashioned but handsome) ligatures on "st", "ct", and "sp".
     *
     * You'll need to add "&subset=all" if you're using it from Google Fonts:
     *   https://fonts.googleapis.com/css?family=Libre+Baskerville&subset=all
     */
    font-variant-ligatures: common-ligatures discretionary-ligatures;
    font-feature-settings: 'liga' on, 'dlig' on;
  }
  
  /* DEFAULTS */
  * {
    box-sizing: border-box;              /* Element width/height includes the border. */
  }
  
  *:target {
    background-color: #ff6;              /* Highlight elements in URL fragment, e.g. #some-header, or #footnote-1. */
  }
  
  html {
    background-color: #eee;              /* Neutral background to contrast with the page. */
    color: var(--color-text);            /* Slightly less "harsh" black; looks subtly better. */
         tab-size: 4;                    /* Tab size of 4 is probably more common in editors etc. */
    -moz-tab-size: 4;                    /* Still needed as of Jan 2019 :-( https://bugzil.la/737785 */
  }
  
  html, body {
    margin: 0;                           /* No extra margin; shows up in some cases (e.g. when printing). */
  }
  
  body {
      display: flex;                     /* Display as flex. */
      flex-direction: column;            /* Put things underneath eachother, rather than next to each other. */
      align-items: center;               /* Put items in the centre. */
      padding: var(--pad-y) var(--pad-x);
    }
  /* LINKS */
  a {
    color: #00f;                         /* Make sure colour is the same in all browsers. */
    text-decoration: none;               /* Underlining can look "busy"; the colour on its own should be enough. */
    transition: color .2s;               /* Animate the change in colour effect on hover; subtle but noticeable. */
  }
  a:hover {
    text-decoration: underline;          /* Provide some feedback by underlining and changing colour. */
    color: #6491ff;                      /* Light blue */
  }
  a:hover {
    color: #6491ff;                      /* Also change colour of code on hover. */
  }
  
  /* HEADERS */
  
  /* The intention is that there is only one h1 on a page: at the top. If you use
   * h1 different, then you may want to add a border like in the h2. */
  h1 {
    text-align: center;
    padding: .4em 0;                     /* More than default. */
    font-size: 1.7em;                    /* Default of 2em is pretty large. */
    line-height: 1.3;                    /* Otherwise looks funky if it overflows. */
  }
  
  h2 {
    border-bottom: 1px solid var(--color-text);  /* Underline to stand out more. */
    padding-bottom: .2em;                /* Border not too close to the text. */
    font-size: 1.5em;                    /* Default of 1.8em is pretty large. */
  }
  
  h3 {
    font-size: 1.3em;                    /* Default of 1.6em is pretty large. */
  }
  
  h4 {
    font-size: 1.1em;                    /* Slightly larger than default of 1em. */
  }
  
  h5, h6 {
    font-size: 1em;                      /* Don't make h5 and h6 smaller than base font. */
  }
  
  /* BLOCKQUOTE */
  blockquote {
    font-style: italic;   /* Quotations are usually typeset in italics. */
    border-left: medium solid #000;
    padding: 0.5em;
    background: #fff;                  
  }