  Accurate results for nonrelativistic energy, relativistic, QED, and finite
nuclear mass corrections are obtained for $2^1S_{1/2}$, $3^1S_{1/2}$ and
$2^1P_{1/2}$ states of the Li atom and Be$^+$ ion. Our computational approach
uses the Hylleraas basis set with the analytic integration and recursion
relations. From comparison of experimental results for the isotope shifts to
theoretical predictions including nuclear polarizabilities, we obtain nuclear
charge radii for Li and Be isotopes.
