  We present a comprehensive study of the excitation of CI fine-structure
levels along 57 sight lines in the Large and Small Magellanic Clouds. The sight
lines were selected by the detection of H$_2$ in FUSE spectra. Using archival
HST/COS and HST/STIS spectra we detected absorption of CI fine-structure levels
and measured their populations for 29 and 22 sight lines in the LMC and SMC,
respectively. The CI column density ranges from $10^{13}$ to $10^{14}\,{\rm
cm}^{-2}$ for the LMC and $10^{13}$ to $10^{15.4}\,{\rm cm}^{-2}$ for the SMC.
We found excitation of CI fine-structure levels in the LMC and SMC to be 2-3
times higher than typical values in local diffuse ISM. Comparing excitation of
both CI fine-structure levels and H$_2$ rotational levels with a grid of PDR
Meudon models we find that neutral cold gas in the LMC and SMC is illuminated
by stronger UV field than in local ISM ($\chi=5^{+7}_{-3}$ units of Mathis
field for the LMC and $2^{+4}_{-1}$ for the SMC) and has on average higher
thermal pressure ($\log p/k =4.2\pm0.4$ and $4.3\pm0.5$, respectively).
Magellanic Clouds sight lines likely probe region near star-formation sites,
which also affects the thermal state and CI/H$_2$ relative abundances. At the
same time such high measurements of UV field are consistent with some values
obtained at high redshifts. Together with low metallicities this make
Magellanic Clouds to be an interesting test case to study of the central parts
of high redshift galaxies.
