after learning hard i have succed my goal to build my responsive website.
but i have a question about device size and resolution.
now we have phone IN FHD AND HD AND TABLET like pc
my resnposive web site work fine it respect the resolution but where phone or tablet have big resolution the web take same layout as pc

/* Disposition tablet pc : 481px : 768px.*/
@media only screen and (min-width: 481px) {
/* Disposition PC : 769px to max 1232px.*/
@media only screen and (min-width: 768px) {

Thanks to sharing through this thread we know how can make website fully responsive this information is most use full for all website builder or Mobile Website Builder.

but my question is how i can make mobile who have same resolution with pc to have mobille layou layout it if for me litle to explain but i try to explan to this way.
phone is full hd screen : 1020x1920 and my pc
is 768x1033
i set bacroung red for moblie for min widht 480
and blue for min width 769.
my phone have same bacround with pc.

how can i solve it ???