How did Casey Anthony get away with murder?

This question has probably been asked many times but I just feel the need to ask while pointing out some very incriminating evidence. My first point would be that she didnt even report her child Caylee Anthony missing for a while after and to me that makes her very suspicious from the start. Research on Casey's computer has shown she was looking up "How to make chloroform" "How to break necks with your hands" and "Death" on google search. Caylee's body was found in the woods near Casey's house with duct tape over her skull and in bags that were found in Casey's house along with a heart shaped sticker that was also in Casey's house. After her daughter was missing she also got a tattoo that said "Bella Vita" (Beautiful life) and was out at night clubs. Im no lawyer but this seems pretty obvious to me that she did it and she should have to pay the consequences, so how did she get away with all of this evidence against her?