For an 'inline' SVG element you have to apply the styles, inside the svg element itself.
inside the <defs></defs>
tags. Since it has its Own DOM[Document Object Model], Css Apllied to it from Outside, will have no effect.
You have Several different options for embeding an SVG, You can use it inline
as in your example where you declare the <svg></svg>
inside of your html/php document or you can use one of the many other methods listed below;
embed an: ..............................................<img src="../pathtoyourSvg"></img>
embed as an img with a fallback option: <img src="logo.png" srcset="logo.svg" alt="My logo">
use an: ....................................................<object type="image/svg+xml" data="image.svg">
<!-- Your fall back here -->
<img src="image.svg" />
</object>
use: .........................................................<embed type="image/svg+xml" src="image.svg" />
use an: ....................................................<iframe></iframe>
embed the Svg inside of a canvas element using Javascript:
var img = new Image();
img.onload = function() {
ctx.drawImage(img, 0, 0);
}
img.src = "path2your.svg";
You may Also Embed the Svg using Css Background image,
ie:
.mySvgContainer{
background-image:url('PathToMySvg');
}
But from the comments & Questions I have read, this need to be either Url or Base64 encoded, which seems a bit Hacky and not very convenient.
each of them have their own advantages and disadvantages.
Because of security reasons, some SVG embedding methods will block access to external resources including CSS, fonts and javascript. Especially when we have multiple images, ideally our embedding method should be able to refer to a single CSS, font or javascript file (to save resources) and be able to manipulate our embedded SVG.
Also worth mentioning that if you have display:flex; attached to an elemnet or its parent then the width and height values will have no effect on the flex items. So It may appear as 0, 0, in the console.
Some Useful Information & related questions:
Svg Coords & Units w3.org
Svg Width - Height
Applying Styles to an embedded Svg