main.js:5 Uncaught TypeError: Cannot set properties of null (setting 'onclick')
<title>Alura MIDI</title>
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<link rel="stylesheet" href="css/estilos.css"><h1>Alura Midi</h1>
<section class="teclado">
<button class="tecla tecla_pom">Pom</button>
<button class="tecla tecla_clap">Clap</button>
<button class="tecla tecla_tim">Tim</button>
<button class="tecla tecla_puff">Puff</button>
<button class="tecla tecla_splash">Splash</button>
<button class="tecla tecla_toim">Toim</button>
<button class="tecla tecla_psh">Psh</button>
<button class="tecla tecla_tic">Tic</button>
<button class="tecla tecla_tom">Tom</button>
</section>
<audio src="sounds/keyq.wav" id="som_tecla_pom"></audio>
<audio src="sounds/keyw.wav" id="som_tecla_clap"></audio>
<audio src="sounds/keye.wav" id="som_tecla_tim"></audio>
<audio src="sounds/keya.wav" id="som_tecla_puff"></audio>
<audio src="sounds/keys.wav" id="som_tecla_splash"></audio>
<audio src="sounds/keyd.wav" id="som_tecla_toim"></audio>
<audio src="sounds/keyz.wav" id="som_tecla_psh"></audio>
<audio src="sounds/keyx.wav" id="som_tecla_tic"></audio>
<audio src="sounds/keyc.wav" id="som_tecla_tom"></audio>
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