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Started</span></a> <!----></li><li class="nav-item"><div class="nav-link"><span class="title">Basics</span></div> <ul class="nav bd-sidenav level1"><li class="nav-item"><a href="/handbook/en/basics/download" class="nav-link"><span class="title">Download ECharts</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/basics/import" class="nav-link"><span class="title">Import ECharts</span></a> <!----></li><!----><li class="nav-item"><a href="/handbook/en/basics/inspiration" class="nav-link"><span class="title">Inspiration</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/basics/help" class="nav-link"><span class="title">Get Help</span></a> <!----></li><li class="nav-item"><a class="nav-link"><span class="title">Release Note</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li></ul></li><li class="nav-item"><div class="nav-link"><span class="title">Concepts</span></div> <ul class="nav bd-sidenav level1"><li class="nav-item"><a href="/handbook/en/concepts/chart-size" class="nav-link"><span class="title">Chart Container</span></a> <!----></li><!----><!----><li class="nav-item"><a href="/handbook/en/concepts/style" class="nav-link"><span class="title">Style</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/concepts/dataset" class="nav-link"><span class="title">Dataset</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/concepts/data-transform" class="nav-link"><span class="title">Data Transform</span></a> <!----></li><!----><li class="nav-item"><a href="/handbook/en/concepts/axis" class="nav-link"><span class="title">Axis</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/concepts/visual-map" class="nav-link"><span class="title">Visual Mapping</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/concepts/legend" class="nav-link"><span class="title">Legend</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/concepts/event" class="nav-link"><span class="title">Event and Action</span></a> <!----></li></ul></li><li class="nav-item"><div class="nav-link"><span class="title">Application</span></div> <ul class="nav bd-sidenav level1"><li class="nav-item"><a class="nav-link"><span class="title">Common Charts</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li><!----><li class="nav-item"><a class="nav-link"><span class="title">Cross Platform</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li><li class="nav-item"><a class="nav-link"><span class="title">Data</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li><li class="nav-item"><a class="nav-link"><span class="title">Label</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li><li class="nav-item"><a class="nav-link"><span class="title">Interaction</span> <span class="glyphicon glyphicon-menu-down"></span></a> <!----></li></ul></li><li class="nav-item"><div class="nav-link"><span class="title">Best Practice</span></div> <ul class="nav bd-sidenav level1"><!----><li class="nav-item"><a href="/handbook/en/best-practice/canvas-vs-svg" class="nav-link"><span class="title">Canvas vs. SVG</span></a> <!----></li><li class="nav-item"><a href="/handbook/en/best-practice/aria" aria-current="page" class="nav-link nuxt-link-exact-active nuxt-link-active"><span class="title">Aria</span></a> <!----></li></ul></li><li class="nav-item"><div class="nav-link"><span class="title">Edit Handbook</span></div> <ul class="nav bd-sidenav level1"><li class="nav-item"><a href="/handbook/en/meta/edit-guide" class="nav-link"><span class="title">Edit Guide</span></a> <!----></li></ul></li></ul></div></div> <div class="bd-content col-sm-7 pl-sm-2 col-12"><div class="post-content content"><div><div class="post-inner"><div class="nuxt-content"><h1 id="web-accessibility"><a href="#web-accessibility" aria-hidden="true" tabindex="-1"><span class="icon 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