Active Tags and year

Hello,

i try to convert my page to middleman. All has become successfully only set active year and tags i find no soulution.

Yet i use a tag and year cloud in every post, active parts which has the post will be set active. For example post has tag society and 2015 then this has other background as other in the cloud. In python template i set this with;

<a href="{{ content_url(site.prefix, year, 'index.html') }}"{% if year ==   post.date.year %} class="active"{% endif %}>{{ year }}<span>{{ posts|length }}</span>

<a href="{{ tag|tag_url }}"{% if tag in post.tags %} class="active"{% endif %}>{{ tag }}<span>{{ posts|length }}</span></a>

Hope understand what mean.

Thx & Nice Day
Silvio