Using SVG as background image

I can't seem to get this to work as desired. My page changes height based on what content is loaded and if it requires a scroll, the svg doesn't seem to be stretching...

html {
  height: 100%;
  background-image: url(http://www.horizonchampion.eu/themes/projectbase/images/bg.svg);
  background-size: 100% 100%;
  -o-background-size: 100% 100%;
  -webkit-background-size: 100% 100%;
  background-size: cover;
}

<svg width="1024" height="800" xmlns="http://www.w3.org/2000/svg">
        <defs>
            <radialGradient fy="0.04688" fx="0.48047" r="1.11837" cy="0.04688" cx="0.48047" id="svg_2">
                <stop stop-color="#ffffff" offset="0"/>
                <stop stop-opacity="0" stop-color="#eaeaea" offset="1"/>
            </radialGradient>
            <radialGradient fy="0.04688" fx="0.48047" r="1.71429" cy="0.04688" cx="0.48047" id="svg_5">
                <stop stop-color="#ffffff" offset="0"/>
                <stop stop-opacity="0" stop-color="#eaeaea" offset="1"/>
            </radialGradient>
         </defs>
         <g display="inline">
            <title>Layer 1</title>
            <rect fill="#eaeaea" stroke-width="0" x="0" y="0" width="1024" height="800" id="svg_1"/>
        </g>
         <g>
              <title>Layer 2</title>
              <rect id="svg_3" height="282" width="527" y="1" x="1" stroke-width="0" fill="url(#svg_2)"/>
              <rect id="svg_4" height="698" width="1021.99999" y="1" x="1" stroke-width="0" fill="url(#svg_5)"/>
         </g>
    </svg>

Is it possible to do this with just CSS3? I'd like to not have to load ANOTHER JS library or call...Any ideas? Thanks!

With my solution you're able to get something similar:

Here is bulletproff solution:

Your html: <input class='calendarIcon'/>

Your SVG: i used fa-calendar-alt

(any IDE may open svg image as shown below)

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512">
  <path d="M148 288h-40c-6.6 0-12-5.4-12-12v-40c0-6.6 5.4-12 12-12h40c6.6 0 12 5.4 12 12v40c0 6.6-5.4 12-12 12zm108-12v-40c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v40c0 6.6 5.4 12 12 12h40c6.6 0 12-5.4 12-12zm96 0v-40c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v40c0 6.6 5.4 12 12 12h40c6.6 0 12-5.4 12-12zm-96 96v-40c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v40c0 6.6 5.4 12 12 12h40c6.6 0 12-5.4 12-12zm-96 0v-40c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v40c0 6.6 5.4 12 12 12h40c6.6 0 12-5.4 12-12zm192 0v-40c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v40c0 6.6 5.4 12 12 12h40c6.6 0 12-5.4 12-12zm96-260v352c0 26.5-21.5 48-48 48H48c-26.5 0-48-21.5-48-48V112c0-26.5 21.5-48 48-48h48V12c0-6.6 5.4-12 12-12h40c6.6 0 12 5.4 12 12v52h128V12c0-6.6 5.4-12 12-12h40c6.6 0 12 5.4 12 12v52h48c26.5 0 48 21.5 48 48zm-48 346V160H48v298c0 3.3 2.7 6 6 6h340c3.3 0 6-2.7 6-6z"/>
</svg>

To use it at css background-image you gotta encode the svg to address valid string. I used this tool (name: URL Decoder—Convert garbled address)

As far as you got all stuff you need, you're coming to css

.calendarIcon{
      //your url will be something like this:
      background-image: url("data:image/svg+xml,***<here place encoded svg>***");
      background-repeat: no-repeat;
    }

Note: these styling wont have any effect on encoded svg image

.{
      fill: #f00; //neither this
      background-color: #f00; //nor this
}

because all changes over the image must be applied directly to its svg code

<svg xmlns="" path="" fill="#f00"/></svg>

To achive the location righthand i copied some Bootstrap spacing and my final css get the next look:

.calendarIcon{
      background-image: url("data:image/svg+xml,%3Csvg...svg%3E");
      background-repeat: no-repeat;
      padding-right: calc(1.5em + 0.75rem);
      background-position: center right calc(0.375em + 0.1875rem);
      background-size: calc(0.75em + 0.375rem) calc(0.75em + 0.375rem);
    }

You can try removing the width and height attributes on the svg root element, adding preserveAspectRatio="none" viewBox="0 0 1024 800" instead. It makes a difference in Opera at least, assuming you wanted the svg to stretch to fill the entire region defined by the CSS styles.

Try placing it on your body

body {
    height: 100%;
    background-image: url(../img/bg.svg);
    background-size:100% 100%;
    -o-background-size: 100% 100%;
    -webkit-background-size: 100% 100%;
    background-size:cover;
}

Set Background svg with content/cart at center

.login-container {
  justify-content: center;
  align-items: center;
  display: flex;
  height: 100vh; 
  background-image: url(/assets/images/login-bg.svg);
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}

You have set a fixed width and height in your svg tag. This is probably the root of your problem. Try not removing those and set the width and height (if needed) using CSS instead.

Check if the svg is a transparent design, try adding a background colour to container and check if it is visible for a different background colour.