Design trends are vague; conventions are specific. These are the ones a site is measured against now, and each is checkable rather than a matter of taste.
Layout and responsiveness
One fluid layout rather than a desktop design with a separate mobile version. Content that reflows rather than requiring horizontal scrolling at any width. Containers with sensible maximum widths instead of a fixed 960 or 1140 pixels.
The single most dated signal is a page that only really works at one window size.
Typography and reading comfort
Body text at sixteen pixels or above. Line height around 1.5 for paragraphs. Line lengths capped so text doesn't run the full width of a wide monitor. A type scale where each level is distinguishable at a glance.
Older sites almost universally fail on the first two, which is why they feel cramped even when the layout is fine.
Interaction and states
Visible focus indicators, because removing them for tidiness breaks keyboard use. Tap targets around forty-four pixels. Form fields with persistent labels rather than placeholders that vanish on focus. Loading and empty states that say something.
These are the details that distinguish an interface built to current expectations from one built to 2015's.
Common questions
How do I know if my site is out of date?
Check it against the list above on a phone. Text under sixteen pixels, missing focus rings and horizontal scrolling are the fastest tells.
Do I have to modernize everything at once?
No, but consistency is most of the benefit — a half-modernised site often looks worse than one that's uniformly dated.
Will modernizing change my brand?
Colours and imagery come from your existing page. What changes is how they're applied, not what they are.
Is this the same as a redesign?
It's a redesign with a specific brief — bring the page in line with current conventions rather than reconsider what it's for.
Run the checklist against your homepage on a phone, then generate the corrected version.