How to convert existing site

without losing speed.

By @JAME5C43

what do you mean ?

how much time it would take to convert my simple squirrel site to other design...

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Hi @JAME5C43,

How long is a piece of string?   I have no idea what a "simple squirrel site" means and no one else does either. 

• What's the URL to your current site?
• How much responsive web design experience do you have?
• Are you able to work with modern code in HTML5, CSS and JavaScript?

to complete what say Ben, the first point you have to verify is ... "how your web site is build"; actually, is there is any use of CSS et good structure of your HTML.

In that cas you will have to remove entirely your CSS, and get a naked HTML web site, where just the HTML is use for rendering as browser see it by default... and from there you will rebuild your own design using CSS

there is a very very very old web site that was proposing to developper to express their own vision of design based on the same HTML for every start... http://www.csszengarden.com/ but I never saw such a verbose structure... ID and CLASS everywhere... on each TAG... any way that will help you to get the idea.

for exploring CSS, you will find plenty web site out there... but personnaly, I often recommand these links

• https://developer.mozilla.org/en-US/docs/Learn/Getting_started_with_the_web/CSS_basics
• https://developer.mozilla.org/en-US/docs/Web/CSS

but, that's not just it,  you also will have to explore the responsive aspect to your web site to adapt the design (still using CSS and Mediaqueries) depending on the device... here too... you will find a very old web site to reflect this idea... well, here it's about different HTML on each case study... https://mediaqueri.es/ but again, that will give you idea.

where to start.. well, here some links :

• https://developer.mozilla.org/en-US/docs/Web/CSS/Media_queries
• https://developer.mozilla.org/en-US/docs/Learn/CSS/CSS_layout/Media_queries
• https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queries/Using_media_queries

Now as Ben previously said, all this can be coded using any code editor, including of course Dreamweaver

Please explain what you mean when you say that you want to convert. 

There is no such thing as a Dreamweaver site, all static sites consist of HTML with, most likely, CSS and JS. Dynamic sites will be coded using serverside coding language like PHP. These sites can be coded using Dreamweaver or any other text editor.