Try changing line 1965 to look like this –
.site-header .widget-area {
color: #ddd;
float: none;
text-align: center;
width: auto;
}
I changed “float: right” to “none” and “text-align: right” to “center“. You may need to make more adjustments once we see what it looks like, but try that first and let me know what happens.
You could also look at the code that changes when the responsive css kicks in (when the browser is resized) since it’s automatically centered.