Display problem on user control panel

dc-testing.dutchcorns.com/
HikaShop Starter: 2.2.0
Joomla 3.1.4
PHP Version 5.3.26
Displays problem in all browsers and versions

Hi. Hope you can help.
I have a big problem with the display of the hikashop user control panel (please see attached image).
The site is using the Joomla standard template Protostar and when going to the user control panel page the layout is all wrong.
I realise that this is probably a template issue but I was kind of hoping that hikashop would at least work with the Joomal standard templates.

I have made no customisation to the standard template so the code is all clean.
Does anyone have any solutions?

Thanks for looking Jerome.
The site cache is switched off and there are no plugins making any optimisation.
I have managed to get the css loading though but only by manually adding the call into the template main page html file.
But even when this is added it is still not displaying correctly, it shows with text under the buttons?

Hi Nicolas. I have activated the account you created. You should be able to log in now.

Cheers

Ok. thanks Jerome. On investigation Hikashop general display settings were set to none for the css on the front end. This has now been changed to default and is now adding the css into the page as it should be. An oversight on my part.

This still has not fixed the issue of the text though. Firebug is displaying that the text is using a span class of 'hikashop_cpanel_button_text' although I cannot find this class anywhere.

I have managed to fumble a way round my problem by changing line 478 of the frontend_default css file to margin-bottom:35px. This has opened the gaps between the buttons to show the text clearly but the text should be inside with the icons.
Does anyone have any idea why it is appearing outside?

All sorted thanks Nicolas and Jerome for your help pinning this down. I changed the css to your suggestion Nicolas and it almost did it.
I had to alter it just slightly to the following and change one line in the template css (as shown below in green):

Frontend_default.css
#hikashopcpanel span {
display:block;
text-align:center;
background-repeat: no-repeat;
background-position: center;
margin-top: 5px;
}

Protostar - template.css - line 5314
.row-fluid [class*="span"] {
display: block;
width: 100%;
min-height: 38px; - was 28px
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
float: left;
margin-left: 2.127659574%;
*margin-left: 2.0744680846383%;
}

Result:

This all being said, in the long run it may be worth changing the hikashop css to override that margin and min-height rather than change the template css as the template is installed as part of joomla and I feel it shouldn't need altering to accommodate the shop component.
Had it been a third party template installed after Joomla then it would be a different story and I would have contacted the templates maker.

Cheers