毎回調べるの面倒だからチートシート的な。
<!DOCTYPE html> <html lang="ja"> <head> <style type="text/css"> body { background: #E0FFFF; } div { width: 0; height: 0; margin-bottom: 10px; } .arrow-top { border-left: 100px solid transparent; border-right: 100px solid transparent; border-bottom: 100px solid red; } .arrow-bottom { border-left: 100px solid transparent; border-right: 100px solid transparent; border-top: 100px solid yellow; } .arrow-left { border-left: 100px solid transparent; border-right: 100px solid green; border-bottom: 100px solid transparent; border-top: 100px solid transparent; } .arrow-right { border-left: 100px solid purple; border-right: 100px solid transparent; border-bottom: 100px solid transparent; border-top: 100px solid transparent; } .arrow-top.opa { border-left: 100px solid transparent; border-right: 100px solid transparent; border-bottom: 100px solid rgba(0, 0, 255, 0.5); } </style> </head> <body> <div class="arrow-top"></div> <div class="arrow-bottom"></div> <div class="arrow-left"></div> <div class="arrow-right"></div> <div class="arrow-top opa"></div> </body> </html>
表示はこんな感じ。
一番下は透過。
positionで位置指定して四角と組み合わせれば吹き出しっぽく。