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HTML

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="container header">
    <header>
        <hgroup>
            <h1>Pure CSS folded-corner effect</h1>
        </hgroup>
        <p><em>Known support</em>: Firefox 3.5+, Chrome 4+, Safari 4+, Opera 10+, IE 8+.</p>
    </header>
</div>

<div class="note">
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris pulvinar rhoncus risus, vel ornare lacus sagittis sit amet. Duis vel sem magna. Proin pulvinar velit eleifend ligula ultrices vestibulum. Nunc posuere dolor eu mauris feugiat dignissim.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris pulvinar rhoncus risus, vel ornare lacus sagittis sit amet. Duis vel sem magna. Proin pulvinar velit eleifend ligula ultrices vestibulum. Nunc posuere dolor eu mauris feugiat dignissim.</p>
</div>

<div class="note red rounded">
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris pulvinar rhoncus risus, vel ornare lacus sagittis sit amet. Duis vel sem magna. Proin pulvinar velit eleifend ligula ultrices vestibulum. Nunc posuere dolor eu mauris feugiat dignissim.</p>
</div>

<div class="note blue">
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris pulvinar rhoncus risus, vel ornare lacus sagittis sit amet. Duis vel sem magna. Proin pulvinar velit eleifend ligula ultrices vestibulum. Nunc posuere dolor eu mauris feugiat dignissim.</p>
</div>

<div class="note taupe">
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris pulvinar rhoncus risus, vel ornare lacus sagittis sit amet. Duis vel sem magna. Proin pulvinar velit eleifend ligula ultrices vestibulum. Nunc posuere dolor eu mauris feugiat dignissim.</p>
</div>

<div class="container footer">
    <p>Pure CSS folded-corner effect.</p>
   
</div>
!

CSS 

              
                 html, body                             {padding:0; margin:0; font:1em/1.4 Cambria, Georgia, sans-serif; color:#333; background:#fff;}
      header, hgroup                         {display:block;}

      a:link, a:visited                      {border-bottom:1px solid #c55500; color:#c55500; text-decoration:none;}
      a:visited                              {border-bottom:1px solid #730800; color:#730800;}
      a:hover, a:focus, a:active             {border:0; color:#fff; background:#c55500;}
      a:visited:hover,
       a:visited:focus,
       a:visited:active                      {color:#fff; background:#730800;}

      .container                             {width:540px; padding:0 0 10px; margin:0 auto 30px;}
      .header                                {border-bottom:1px solid #ddd;}
      .footer                                {padding:10px 0 30px; border-top:1px solid #ddd; margin-bottom:0;}

      h1                                     {margin:1em 0 0; font-size:2.5em; font-weight:normal; line-height:1.2; text-align:center;}
      h2                                     {margin:0.5em 0 1.5em; font-size:1.25em; font-weight:normal; font-style:italic; text-align:center;}
      p                                      {margin:1em 0; line-height:1.4em;}

      pre                                    {margin:1.4em 0; font-size:12px; line-height:1.4em; white-space:pre-wrap; word-wrap:break-word;}

      .follow                                {clear:both; margin-top:2em; font-size:1.125em;}
      .follow span                           {font-weight:bold;}


      /* == FOLDED CORNERS */

      .note {
          position:relative;
          width:480px;
          padding:1em 1.5em;
          margin:2em auto;
          color:#fff;
          background:#97C02F;
          overflow:hidden;
      }

      .note:before {
          content:"";
          position:absolute;
          top:0;
          right:0;
          border-width:0 16px 16px 0; /* This trick side-steps a webkit bug */
          border-style:solid;
          border-color:#fff #fff #658E15 #658E15; /* A bit more verbose to work with .rounded too */
          background:#658E15; /* For when also applying a border-radius */
          display:block; width:0; /* Only for Firefox 3.0 damage limitation */
          /* Optional: shadow */
          -webkit-box-shadow:0 1px 1px rgba(0,0,0,0.3), -1px 1px 1px rgba(0,0,0,0.2);
          -moz-box-shadow:0 1px 1px rgba(0,0,0,0.3), -1px 1px 1px rgba(0,0,0,0.2);
          box-shadow:0 1px 1px rgba(0,0,0,0.3), -1px 1px 1px rgba(0,0,0,0.2);
      }

      .note.red {background:#C93213;}
      .note.red:before {border-color:#fff #fff #97010A #97010A; background:#97010A;}

      .note.blue {background:#53A3B4;}
      .note.blue:before {border-color:#fff #fff transparent transparent; background:transparent;}

      .note.taupe {background:#999868;}
      .note.taupe:before {border-color:#fff #fff #BDBB8B #BDBB8B; background:#BDBB8B;}

      /* ROUNDED CORNERS VERSION
       * All modern browsers can produce this effect with a single pseudo-element.
       * However, they all have bugs (mainly to do with border-radius) that make this a bit tricky.
       * As far as I can tell, this is the only cross-browser method for the moment.
       * Can't use this method for the simple effect because Opera 11 will only show backgrounds
       * through transparent borders if there is a border-radius applied.
       */

      .note.rounded {
          -webkit-border-radius:5px 0 5px 5px;
          -moz-border-radius:5px 0 5px 5px;
          border-radius:5px 0 5px 5px;
      }

      .note.rounded:before {
          border-width:8px; /* Triggers a 1px 'step' along the diagonal in Safari 5 (and Chrome 10) */
          border-color:#fff #fff transparent transparent; /* Avoids the 1px 'step' in webkit. Background colour shows through */
          -webkit-border-bottom-left-radius:5px;
          -moz-border-radius:0 0 0 5px;
          border-radius:0 0 0 5px;
      }

      .note p {margin:0;}
      .note p + p {margin:1.5em 0 0;}
!

JS
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999px

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