attention danger germany isolated pictogram safety sign traffic uneven road warning limit radar road speed stop crossing crossover crosswalk pedestrian public street zebra advice alert appropriate-behavior appropriate-behaviour black care cars caution communicate communication denied information informing law legal no-standing not-allowed not-permitted park permission-denied prohibited prohibition red refusal restricted restriction restrictions risk risks risky road-safety road-side signs sky unacceptable vehicles verge warning-sign white blue dangerous penalties clearway directions keep-clear no-parking no-temporary-parking access-denied parking signage go lights signal signs full stop Stop light big brother camera car limits regulations surveillance vehicle