Font-size property not applied to h5

Steps to replicate

1. Install confluence 5.7
2. Apply the following customization in Pdf stylesheet:

   body, p, li, td, table, tr, .bodytext, .stepfield {
   word-wrap: normal;
   }
   .wiki-content p {
   word-wrap: normal;
   }
   .fsTitlePage {
   margin-left: auto;
   margin-top: 50mm;
   margin-right: auto;
   page-break-after: always;
   }
   .fsTitle {
   font-size: 42px;
   font-weight: bold;
   margin: 72px 0 4px 0;
   text-align: center;
   }
   h1 {
   font-size: 60px;
   page-break-before: always;
   color: red;
   }
   h2 {
   font-size: 48px;
   page-break-before: always;
   color: green;
   }
   h3 
   {
   font-size: 36px;
   page-break-before: always;
   color: blue;
   }
   h4 {
   font-size: 30px;
   margin: 0;
   padding-top: 30px;
   padding-bottom: 4px;
   color: yellow;
   }
   h5 {
   font-size: 74px;
   margin: 0;
   padding-top: 6px;
   padding-bottom: 4px;
   font-style: italic;
   color: brown;
   }
   h6 {
   font-size: 14px;
   margin: 0;
   padding-top: 6px;
   padding-bottom: 4px;
   font-style: italic;
   color: brown;
   }
   h7 {
   font-size: 12px;
   margin: 0;
   padding-top: 4px;
   padding-bottom: 4px;
   color: black;
   }
   h8 {
   font-size: 12px;
   margin: 0;
   padding-top: 2px;
   padding-bottom: 4px;
   color: grey;
   }
   body,p,li,td,table,tr,.bodytext,.stepfield {
   font-size: 11pt;
   }
   

3. Export a space

Observed behaviour
Font-size property not applied to h5

Expected behaviour
The size of font should change