PlotLegends Below and Inside of a frame

Question

I whis to make that my labels are inside of the frame, as is shown in the following figure:

How can I do it? The best that I did is with the following code:

Plot[{Sin[x], Cos[x]}, {x, 0, 28.27]}, Frame -> True, 
 PlotRange -> {-1.5, 1.5}, 
 PlotLegends -> Placed["Expressions", {Below, Center}]]

Thanks for your help!

Answer 1

You can also use the symbolic position {Center, Bottom} but it gives a column layout for the legends:

 Plot[{Sin[x], Cos[x]}, {x, 0, 28.27}, Frame -> True, 
    PlotRange -> {-1.5, 1.5}, 
    PlotLegends -> Placed["Expressions", {Center, Bottom}]] 

which is easily modified with a simple replacement:

 % /. "Column" -> "Row" 

Answer 2

Plot[{Sin[x], Cos[x]}, {x, 0, 28.27}, Frame -> True, 
 PlotRange -> {-1.5, 1.5}, 
 PlotLegends -> Placed["Expressions", {{.5, 0}, {.5, -.5}}]]