JSFiddle - React, Tailwind, and code Playground

HTML

<div id="grid">
    <table width="100%" cellspacing="0" cellpadding="0">
  <tbody><tr class="gridHeader">
    <td>&nbsp;</td>
    <td class="underline">09:00</td>
    <td class="underline">10:00</td>
    <td class="underline">11:00</td>
    <td class="underline">12:00</td>
    <td class="underline">13:00</td>
    <td class="underline">14:00</td>
    <td class="underline">15:00</td>
    <td class="underline">16:00</td>
    <td class="underline">17:00</td>
  </tr>
  <tr id="mon">
    <td class="gridSide">Mon</td>
    
    <td class="box" id="mon1">&nbsp;</td>
		
    <td class="box" id="mon2">&nbsp;</td>
		
    <td class="box" id="mon3">&nbsp;</td>
		
    <td class="box" id="mon4">&nbsp;</td>
		
    <td class="box" id="mon5">&nbsp;</td>
		
    <td class="box" id="mon6">&nbsp;</td>
		
    <td class="box" id="mon7">&nbsp;</td>
		
    <td class="box" id="mon8">&nbsp;</td>
		
    <td class="box" id="mon9">&nbsp;</td>
		  </tr>
  <tr id="tue">
    <td class="gridSide">Tue</td>
    
    <td class="box" id="tue1">&nbsp;</td>
		
    <td class="box" id="tue2">&nbsp;</td>
		
    <td class="box" id="tue3">&nbsp;</td>
		
    <td class="box" id="tue4">&nbsp;</td>
		
    <td class="box" id="tue5">&nbsp;</td>
		
    <td class="box" id="tue6">&nbsp;</td>
		
    <td class="box" id="tue7">&nbsp;</td>
		
    <td class="box" id="tue8">&nbsp;</td>
		
    <td class="box" id="tue9">&nbsp;</td>
		  </tr>
  <tr id="wed">
    <td class="gridSide">Wed</td>
      
    <td class="box" id="wed1">&nbsp;</td>
		
    <td class="box" id="wed2">&nbsp;</td>
		
    <td class="box" id="wed3">&nbsp;</td>
		
    <td class="box" id="wed4">&nbsp;</td>
		
    <td class="box" id="wed5">&nbsp;</td>
		
    <td class="box" id="wed6">&nbsp;</td>
		
    <td class="box" id="wed7">&nbsp;</td>
		
    <td class="box" id="wed8">&nbsp;</td>
		
    <td class="box" id="wed9">&nbsp;</td>
		  </tr>
  <tr id="thu">
    <td class="gridSide">Thu</td>
    
    <td class="box" id="thu1">&nbsp;</td>
		
    <td class="box"...

CSS

.gridHeader {
	color: #000;
	background-color: #EAEAEA;
	font-size: 12px;
}
.gridHeader:hover {
	color: #000 !important;
	font-size: 12px;
}
.gridSide {
	color: #000;
	background-color: #EAEAEA;
	font-size: 28px;
	border-right: thin solid #ACACAC;
	;
}
.underline {
	border-bottom: thin solid #ACACAC;
}
.box {
	border-bottom: thin solid #ACACAC;
	border-right: thin solid #ACACAC;
	font-size: 10px;
	text-align: center;
	color: #000 !important;
}
.box:hover {
	background-color: #EAEAEA;
	color: #000 !important;
}