architecture berlin building buildings business city cityscape germany glass house modern office offices shape shaped skyscraper street scenery tower triangle triangular urban window windows work workplace arrows black circular communicating communication curved directing direction directional give-way indication indicator informing red reflective roundabout sign speed reduction street sign traffic traffic flow white abstract background christmas concept creation daylight design fill foil frame geometric graphic green metal metallic New opaque original pattern pretty scrapbooking shiny texture triangles unique xmas blue aluminium block diamonds England english futuristic Gherkin gray Great Britain grey iconic landmark London power reflections silver British Museum ceiling clouds construction curve dome Great Court lattice museum roof sky structure transparent gold yellow pink purple