1 / The correct sequence of media queries.
From smaller to bigger (min-width: 768px -> 1200px -> 1366pxpx):
@media (min-width: 768px) { ... } @media (min-width: 1200px) { ... } @media (min-width: 1366pxpx) { ... }
From larger to smaller (max-width: 1366pxpx -> 1200px -> 768px):
@media (max-width: 1366px) { ... } @media (max-width: 1200px) { ... } @media (max-width: 768px) { ... }
Such a scheme helps me to remember.
2 / Adaptation of wrappers (.wrap, .container) and other blocks.
.wrap { max-width: 1200px; width: 100%; }
or
.container { width: 90%; }
3 / Adaptation of images and other media objects
img { max-width: 100%; width: 100%; height: auto; }
4 / Location of blocks
Cancel float if necessary, use flex or other markup.
5 / Various other factors (extra padding, fixed block width, font, ...)
It is also recommended to use box-sizing (not entirely due to adaptation, just advice)
*, *:before, *:after { -webkit-box-sizing: border-box; -moz-box-sizing: border-box; box-sizing: border-box; }
In simple words, the point is that the adaptive layout provides for the normal display of the site on various devices (tablets, phones). Those. possible resizing blocks, fonts. Change the location of the blocks.
PS: Everything is relative and generalized. For each case, you need to look at the problem.
TIP: On the Internet already a lot of lessons and examples of adaptive layout, look!