navigate to
reputation_add template of your forum's active theme
1
change
<body> to below code
<body style="text-align: left!important;">
2
find
style="width: 95%" and change it to
style="width: 35%"
3
find
<div style="text-align: center;"> and change to below code
<div style="text-align: left;">
save the template and check the reputation popup.