Responsive design

In short
Responsive design means the same website adapts to any screen width: columns stack, images scale, the menu folds away. There is one version of the page and one address — the adaptation happens in the browser. Today that is the baseline, not an added service.
Adapting is not the same as usable
A page can reflow flawlessly and still be unusable on a phone: an eight-column table, a form field running past the edge, a button too small for a thumb.
The test is the task, not the rendering. Can somebody send an enquiry one-handed, on a train, on a phone? If not, the page is responsive and has still failed.
The mistake we see most
The order of work. Design on a large screen and «adapt it for mobile» afterwards, and every decision gets made under conditions that do not apply to most visitors — leaving you to cut things on the small screen rather than rank them.
Starting from the narrowest width forces the opposite question: what genuinely comes first? What holds up there holds up on a large screen too. The reverse does not follow.
Why it counts for visibility
Google evaluates pages on their mobile version. Anything not served to a phone is therefore absent from that evaluation — content a layout hides on narrow screens is content that does not count.
Load time compounds it: sending a full-resolution image to a mobile device costs seconds, and seconds measurably cost visitors. Design decides a figure here that usually gets filed under engineering.
How we handle it
We design from the narrowest width up and check every page on a real device, not only in a shrunken window — the two behave differently. Context: ALPENIQ Studio and website development.
The test that reveals the most: pick up your own phone and try to send yourself an enquiry through your own site. Unaided.
Related terms
A term in your quote that nobody explained?
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