BibLaTeX - change how citing shows the pages

Question

I'm using the code in the end and I'm having this result:

I'd like to change the format of the pages just in the citation, and not in the bibliography, to:

(Nunes, 2013: 6-7)

I've tried reading the biblatex package pdf and even looking at the biblatex_.def but my LaTeX knowledge is small and failing me.

PS: Why is the space missing before the google maps link?

\documentclass{article}
\usepackage[portuguese]{babel}
\usepackage{csquotes}
\usepackage[backend=biber,style=authoryear,dashed=false,backref=true]{biblatex}
\renewcommand\nameyeardelim{\addcomma\addspace}
\DefineBibliographyStrings{portuguese}{%
  url={Disponível em},
}
\DeclareFieldFormat{url}{\bibstring{url}\addcolon\space\url{#1}}
\DeclareFieldFormat{urldate}{\mkbibbrackets{#1}}

\addbibresource{\jobname.bib}
\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@online{WHO1,
    author = {World{\ }Health{\ }Organization},
    shortauthor = {WHO},
    title = {The Ottawa Charter for Health Promotion},
    year = {1986},
    url = {http://www.who.int/healthpromotion/conferences/previous/ottawa/en/},
    urldate = {2015-03-31},
}

@online{Google,
    author = {Google{\ }Maps},
    note = {Servico online},
    year = {2015},
    url = {https://maps.google.com/},
    urldate = {2015-04-01},
}

@thesis{Nunes,
    author = {Nelson Filipe Nunes},
    title = {Planeador colaborativo de deslocacoes de bicicleta em meio urbano},
    year = {2013},
    institution = {Instituto Superior Tecnico, Universidade de Lisboa},
    location = {Lisboa, Portugal},
    note = {Dissertacao para obtencao do Grau de Mestre em Engenharia Informatica e de Computadores},
    pages = {10-20},
}
\end{filecontents}

\begin{document}

\parencite{WHO1}
...
\parencite[6-7]{Nunes}
...
\textcite{Google}

\printbibliography

\end{document}