diff --git a/docs/backup.md b/docs/backup.md
index 027277c8..5aa5b5d8 100644
--- a/docs/backup.md
+++ b/docs/backup.md
@@ -48,7 +48,7 @@ This will do the following:
 
 * Automated pruning of backup files, daily kept for 2 weeks, weekly for 2 months and monthly for 1 year. To calculate estimated disk needs, take the size of a manual backup and * 37. eg 600MB backup * 37 = 22.2GB of space needed. <br>
  <form>
-        Calculate Backup Size (in GB): <input type="text" id="firstNumber" style="width: 100px;" /> * <input type="text" id="secondNumber" style="width: 30px;" value = "37" />GB <input type="button" onClick="multiplyBy()" Value="Calculate" /> = Total Space needed <span id="result"></span>GB</form> 
+        Calculate Backup Size (in GB): <input type="text" id="firstNumber" style="background-color: #f0f0f0;  color: #000000; width: 100px;" /> * <input type="text" id="secondNumber" style="background-color: #f0f0f0;  color: #000000; width: 30px;" value = "37" />GB <input type="button" onClick="multiplyBy()" Value="Calculate" style="background-color: #f0f0f0;  color: #000000;" /> = Total Space needed <span id="result"></span>GB</form> 
 
 !!!warning
     The backup script will just save to your server drive, you ideally want to automate moving this to another server. Please ensure you have space for the backups to be stored.