1. The first question in about the colour of the bell notifications the red I want to be different colour instead of little circled red one here...

2. After clicking on the notifications bell, I have the notifications but then suddenly they get disappeared how can I fix this? In the way notifications to stay just like here in codoforum... here you can see how it looks like after clicking for the second time.

3. I want to change the style or let's say ICONS for Reputation points, how can I do this? Because I think instead of plus and minus there should be introduced new VOTING icons which will make our forums a more beautiful environment also it will encourage more users to post.
The problem is not only this, but it gets disappeared if you don't focus your mouse in the reputation area... here you can see on the attachmen... ( so I want to edit these styles)

Hi

You can change the background color of bell by changing the color of the variable @badgeNewRepliesBg in sites/default/themes/default/colors.less

1. After clicking on the notifications bell, I have the notifications but then suddenly they get disappeared how can I fix this? In the way notifications to stay just like here in codoforum... here you can see how it looks like after clicking for the second time

There have been a lot of bug fixes in the new version, so please install the lateste version v3.7

. I want to change the style or let's say ICONS for Reputation points, how can I do this? Because I think instead of plus and minus there should be introduced new VOTING icons which will make our forums a more beautiful environment also it will encourage more users to post.
The problem is not only this, but it gets disappeared if you don't focus your mouse in the reputation area... here you can see on the attachmen...

Again, install 3.7, as there are some style changes to reputation.
You can edit the css in sites/default/themes/default/less/topic.less to change it the way you want.