lg Large devices Desktops (≥1200px) md Medium devices Desktops (≥992px) sm Small devices Tablets (≥768px) xs Extra small devices Phones (<768px)

PCとか結構大きな幅のディスプレイ タブレット横置きの幅～PCぐらい 幅広めスマートフォン？横置き？～タブレット縦ぐらい スマートフォンサイズの幅

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<div id="visibleTester" class="container" style="color: #B1A1A1;border-bottom: solid 1px #ddd;">
<span class="visible-lg hidden-md hidden-sm hidden-xs">lg Large devices Desktops (≥1200px)</span>
<span class="visible-md hidden-sm hidden-lg hidden-xs">md Medium devices Desktops (≥992px)</span>
<span class="visible-sm hidden-md hidden-lg hidden-xs">sm Small devices Tablets (≥768px)</span>
<span class="visible-xs hidden-md hidden-sm hidden-lg">xs Extra small devices Phones (&lt;768px)</span>
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