How to create svg drop shadow?

I'm using a bunch of tutorials to try and get the svg shadow from me, but nothing seems to work!

Here's my fiddle: https://jsfiddle.net/5nfdovg5/

This is what I did:

• Created a gradient fill called "Gradient-1" . This one works :
  • 
• When I add a shadow filter (called "dropshadow" ) it only shows the shadow , and none of the circle that should be on top .. just a black blurred circle:
  • 
• The desired effect I need is here:
  • http://xn--dahlstrm-t4a.net/svg/filters/arrow-with-dropshadow-lighter.svg

Any ideas on what I am doing wrong?

Here's the complete markup:

<svg width="200" height="200">
    <defs>
        <linearGradient id="Gradient-1" x1="20%" y1="30%" x2="40%" y2="80%">
            <stop offset="0%" stop-color="#B8D0DE"></stop>            
            <stop offset="100%" stop-color="#73A2BD"></stop>
        </linearGradient>
        <filter id="dropshadow" xmlns="http://www.w3.org/2000/svg" height="130%">
            <feGaussianBlur in="SourceAlpha" stdDeviation="3">
                <feOffset dx="2" dy="2" result="offsetblur">
                    <feComponentTransfer>
                        <feFuncA type="linear" slope="0.2"></feFuncA>
                    </feComponentTransfer>      
                    <feMerge>
                        <feMergeNode>
                            <feMergeNode in="SourceGraphic"></feMergeNode>
                        </feMergeNode>
                    </feMerge>
                </feOffset>
            </feGaussianBlur>
        </filter>
    </defs> 
    <circle cx="125" cy="125" r="25" filter="url(#dropshadow)" fill="url(#Gradient-1)"></circle>
</svg>