It's no problem. Exit your A gate and walk towards baggage claim / transfers. You'll go up a set of stairs or escalators and see mobile lounge docks to the left and right; terminal B will be straight ahead. Go to your left and board the next shuttle leaving for terminal C. It'll take you there in ten minutes or less. When you arrive at C, look overhead for signs to tell you which direction (left or right) to proceed to your gate.

Whole deal should take maybe 20 minutes, worst case.

Along the way, in the A terminal you can pick up a slicer at Famous Famiglia or a sandwich at Cosi. In C terminal, if you have extra time, Vino Volo at C4 has some nice flights of red, white and sparkling wines; however, with a 60 minute connect you might be a little rushed to really enjoy them. There are other fast food options in C terminal as well; Burger King, Starbuck's, the usual. If your gate is down by the D's (look in the back of Hemispheres for a map) you could pick up a glass of amber at Gordon Biersch over by D8.

Ah, to be in the Bay Area again. Tied House, how I miss you.