diff --git a/index.html b/index.html
index d427f1a..6b9aaf9 100644
--- a/index.html
+++ b/index.html
@@ -62,7 +62,8 @@
       <a href="http://stackoverflow.com/users/4882080" target="_blank"><img src="svg/stackoverflow.svg"/></a>
       <a href="#" onclick="window.open('add-wechat.svg', '', 'width=200,height=225,toolbar=no')"><img src="svg/wechat.svg" /></a>
       <a href="https://www.zhihu.com/people/dennydai" target="_blank"><img src="svg/zhihu.svg" /></a>
-      <a href="https://www.khanacademy.org/profile/dennydai/" target="_blank"><img src="svg/khan.svg" /></a>
+      <a href="https://gyrosco.pe/dennydai/zero/explorer/" target="_blank"><img src="svg/location.svg" /></a>
+      <!--<a href="https://www.khanacademy.org/profile/dennydai/" target="_blank"><img src="svg/khan.svg" /></a>-->
       <a href="https://www.coursera.org/user/i/738227ceaa65446eee7034d5ed981e80" target="_blank"><img src="svg/coursera.svg" /></a>
       <a href="https://plus.google.com/u/0/104064655722567909748" target="_blank"><img src="svg/google+.svg" /></a>
       <a href="http://subset.pool.sks-keyservers.net/pks/lookup?op=get&search=0x8786812140F2EF9E" target="_blank"><img src="svg/openpgp.svg" /></a>
diff --git a/svg/location.svg b/svg/location.svg
new file mode 100644
index 0000000..c2fbb93
--- /dev/null
+++ b/svg/location.svg
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 22.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<svg version="1.1"
+	 id="svg7605" inkscape:export-filename="C:\Users\10000_000\Desktop\twitter.png" inkscape:export-xdpi="90" inkscape:export-ydpi="90" inkscape:version="0.91 r13725" sodipodi:docname="temp.svg" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:svg="http://www.w3.org/2000/svg"
+	 xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="0 0 160.4 50"
+	 style="enable-background:new 0 0 160.4 50;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#EEEEEE;}
+	.st1{enable-background:new    ;}
+	.st2{fill:#3A4750;}
+	.st3{fill:#111111;}
+	.st4{fill:#F4B300;}
+</style>
+<sodipodi:namedview  bordercolor="#666666" borderopacity="1.0" id="base" inkscape:current-layer="layer1" inkscape:cx="70.069522" inkscape:cy="13.725092" inkscape:document-units="px" inkscape:pageopacity="0.0" inkscape:pageshadow="2" inkscape:snap-grids="true" inkscape:snap-page="false" inkscape:snap-to-guides="true" inkscape:window-height="705" inkscape:window-maximized="1" inkscape:window-width="1366" inkscape:window-x="-8" inkscape:window-y="-8" inkscape:zoom="2" pagecolor="#ffffff" showgrid="true" showguides="false" units="px">
+	<inkscape:grid  id="grid8437" type="xygrid"></inkscape:grid>
+</sodipodi:namedview>
+<g id="layer1" transform="translate(0,-1002.3622)" inkscape:groupmode="layer" inkscape:label="Layer 1">
+	<rect id="rect7613" x="0" y="1002.4" class="st0" width="160.4" height="50"/>
+	<g class="st1">
+		<path class="st2" d="M61.5,1034.8H50V1020h2.5v12.6h9.1V1034.8z"/>
+		<path class="st2" d="M75.6,1034.8H64.5v-11.9h11.1V1034.8z M73.3,1032.7v-7.7h-6.5v7.7H73.3z"/>
+		<path class="st2" d="M90.2,1034.8H79.2v-11.9h11.1v2.1h-8.9v7.7h8.9V1034.8z"/>
+		<path class="st2" d="M104.1,1034.9h-11v-7h8.6v-2.7h-5.8v-2.2h8.1V1034.9z M101.7,1032.7v-2.7h-6.3v2.7H101.7z"/>
+		<path class="st2" d="M106.7,1022.9h1.8v-3h2.3v3h4.7v2.2h-4.7v7.5h4.6v2.1h-6.9v-9.6h-1.8V1022.9z"/>
+		<path class="st2" d="M117.4,1022.9h4.1v11.8h-2.3v-9.8h-1.8V1022.9z M121.5,1021.9h-2.3v-2h2.3V1021.9z"/>
+		<path class="st2" d="M136.1,1034.8H125v-11.9h11.1V1034.8z M133.8,1032.7v-7.7h-6.5v7.7H133.8z"/>
+		<path class="st2" d="M150.4,1034.8h-2.3v-9.8h-6.2v9.8h-2.3v-11.9h10.8V1034.8z"/>
+	</g>
+	<circle class="st3" cx="25" cy="1027.4" r="15"/>
+	<g>
+		<path class="st4" d="M27.5,1028.8c-2,2.8-2.3,5.2-2.3,5.2c0,0.2-0.2,0.2-0.3,0c0,0-0.4-2.4-2.3-5.2c-1.6-2.2-2.3-3.1-2.3-4.9
+			c0-2.6,2.1-4.7,4.7-4.7c2.6,0,4.8,2.1,4.8,4.7C29.8,1025.7,28.4,1027.5,27.5,1028.8z M26.9,1024c0-1-0.8-1.8-1.8-1.8
+			c-1,0-1.8,0.8-1.8,1.8s0.8,1.9,1.8,1.9C26.1,1025.9,26.9,1025,26.9,1024z"/>
+	</g>
+</g>
+</svg>