Fill color doesn't work for background SVG images
Hi, just to tell you that this point in the readme is not totally true. You should specify that there are many techniques to define and use icons. You can use svg in different ways and modify his color, even on IE9+. Icon fonts are now considered hacks since there are many approaches with a more specific technology.

### 1. Mask
https://codepen.io/noahblon/post/coloring-svgs-in-css-background-images

```css
.icon {
    background-color: red;
    mask: url(icon.svg) no-repeat 50% 50%;
}
```

---

### 2. As plain svg background
https://css-tricks.com/probably-dont-base64-svg/

```css
  background-image: url('data:image/svg+xml;utf8,<svg ...><g stroke="var(--color)" ... /></g></svg>');
```

---

### 3. Using filters on a 50% gray icon.
http://noahblon.com/coloring-svgs-in-css-background-images/

```css
.icon {
    filter: hue-rotate(220deg) saturate(5);
}
```

---

### 4. Using currentColor
https://css-tricks.com/cascading-svg-fill-color/

```css
svg {
  fill: currentColor;
}

.icon {
  color: red;
}
```

---

### 5. External svg sprite and background

```html
<svg xmlns="http://www.w3.org/2000/svg">

    <symbol id="arrow-left" viewBox="0 0 10 16">
        <path d="M9.4 1.4L8 0 0 8l8 8 1.4-1.4L2.8 8z"/>
    </symbol>

    <symbol id="arrow-right" viewBox="0 0 10 16">
        <path d="M0 14.6L1.4 16l8-8-8-8L0 1.4 6.6 8z"/>
    </symbol>

</svg>
```

```css
.icon{
  background: url("https://path-to-svg-sprite.svg#arrow-right") no-repeat;
}
```

You can combine this with other methods.


