You say you spilled juice in the fan vent? There are a few possible issues here. 1. Don't have any liquids in close enough proximity to any electronic device that you enjoy. Liquids and electronics simply don't mix well. 2. Since you spilled sticky stuff on the fan vent, it is possible that the sticky collected a ton of dust as it dried and now is clogging the air flow up, causing the device to overheat, thus shutting off before complete boot up. 3. Or, the sticky juice has caused a short somewhere. If this is the case, you might want to see if there is a professional who can run some diagnostics to find the issue. Then, price out the cost of replacement versus cost of repair. I would check for excessive dust build up first as that is easiest to fix.

Was it dropped? If it was dropped, the cable that plugs the display into the board could have come out causing the screen to go dark. If not dropped, it might be possible that the display unit needs to be replaced. Cheers

Look up a guide on this site and replace the battery. Batteries only last for so many recharges. In the future, good battery practices are to allow it to run down to approx. 15% and then fully recharge it before using it again. This will help your next battery to last longer. Cheers.