My navi bar messed up

Hello,
You need to first download the plugin: https://wordpress.org/plugins/wp-add-custom-css/
Activate the plugin
Go to Dashboard-> Add Custom Css
Inside CSS rules box, write following code:

.menu-main {
    float: right;
    padding-top: 45px !important;
}

You can resize logo and padding-top as per your requirement.

Thanks!!