React-calendar css overriding isn't applying to the calendar

Question

I am using NextJS and making a calendar component. Issue is I am trying to override the Calendar.css file in the module that it says you can override to make custom styles. I have overridden it my own styles but they aren't taking effect. Then I tried deleting the css file content entirely but it didn't even change the format. It wasn't until I comment out the import css that the style goes back to normal. Is this a React 18/Nextjs bug? I tried it in chrome and firefox and got the same results.

The first picture is a screenshot of what is displayed after applying the default css styling in the module. The second picture is what I would like it to look like after overriding the default css file.

    .react-calendar {
  width: 350px;
  max-width: 100%;
  background: white;
  border: 1px solid #a0a096;
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.125em;
}
.react-calendar--doubleView {
  width: 700px;
}
.react-calendar--doubleView .react-calendar__viewContainer {
  display: flex;
  margin: -0.5em;
}
.react-calendar--doubleView .react-calendar__viewContainer > * {
  width: 50%;
  margin: 0.5em;
}
.react-calendar,
.react-calendar *,
.react-calendar *:before,
.react-calendar *:after {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}
.react-calendar button {
  margin: 0;
  border: 0;
  outline: none;
}
.react-calendar button:enabled:hover {
  cursor: pointer;
}
.react-calendar__navigation {
  display: flex;
  height: 44px;
  margin-bottom: 1em;
}
.react-calendar__navigation button {
  min-width: 44px;
  background: none;
}
.react-calendar__navigation button:disabled {
  background-color: #f0f0f0;
}
.react-calendar__navigation button:enabled:hover,
.react-calendar__navigation button:enabled:focus {
  background-color: #e6e6e6;
}
.react-calendar__month-view__weekdays {
  text-align: center;
  text-transform: uppercase;
  font-weight: bold;
  font-size: 0.75em;
}
.react-calendar__month-view__weekdays__weekday {
  padding: 0.5em;
}
.react-calendar__month-view__weekNumbers .react-calendar__tile {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75em;
  font-weight: bold;
}
.react-calendar__month-view__days__day--weekend {
  color: #d10000;
}
.react-calendar__month-view__days__day--neighboringMonth {
  color: #757575;
}
.react-calendar__year-view .react-calendar__tile,
.react-calendar__decade-view .react-calendar__tile,
.react-calendar__century-view .react-calendar__tile {
  padding: 2em 0.5em;
}
.react-calendar__tile {
  max-width: 100%;
  padding: 10px 6.6667px;
  background: none;
  text-align: center;
  line-height: 16px;
}
.react-calendar__tile:disabled {
  background-color: #f0f0f0;
}
.react-calendar__tile:enabled:hover,
.react-calendar__tile:enabled:focus {
  background-color: #e6e6e6;
}
.react-calendar__tile--now {
  background: #ffff76;
}
.react-calendar__tile--now:enabled:hover,
.react-calendar__tile--now:enabled:focus {
  background: #ffffa9;
}
.react-calendar__tile--hasActive {
  background: #76baff;
}
.react-calendar__tile--hasActive:enabled:hover,
.react-calendar__tile--hasActive:enabled:focus {
  background: #a9d4ff;
}
.react-calendar__tile--active {
  background: #006edc;
  color: white;
}
.react-calendar__tile--active:enabled:hover,
.react-calendar__tile--active:enabled:focus {
  background: #1087ff;
}
.react-calendar--selectRange .react-calendar__tile--hover {
  background-color: #e6e6e6;
}

This is the default css style.

.react-calendar { 
 width: 400px;
 max-width: 100%;
 background-color: #fff;
 color: #222;
 border-radius: 8px;
 box-shadow: 0 12px 24px rgba(0, 0, 0, 0.2);
 font-family: Arial, Helvetica, sans-serif;
 line-height: 1.125em;
}
.react-calendar__navigation button {
 color: #6f48eb;
 min-width: 44px;
 background: none;
 font-size: 16px;
 margin-top: 8px;
}
.react-calendar__navigation button:enabled:hover,
.react-calendar__navigation button:enabled:focus {
 background-color: #f8f8fa;
}
.react-calendar__navigation button[disabled] {
 background-color: #f0f0f0;
}
abbr[title] {
 text-decoration: none;
}
/* .react-calendar__month-view__days__day--weekend {
 color: #d10000;
} */
.react-calendar__tile:enabled:hover,
.react-calendar__tile:enabled:focus {
 background: #f8f8fa;
 color: #6f48eb;
 border-radius: 6px;
}
.react-calendar__tile--now {
 background: #6f48eb33;
 border-radius: 6px;
 font-weight: bold;
 color: #6f48eb;
}
.react-calendar__tile--now:enabled:hover,
.react-calendar__tile--now:enabled:focus {
 background: #6f48eb33;
 border-radius: 6px;
 font-weight: bold;
 color: #6f48eb;
}
.react-calendar__tile--hasActive:enabled:hover,
.react-calendar__tile--hasActive:enabled:focus {
 background: #f8f8fa;
}
.react-calendar__tile--active {
 background: #6f48eb;
 border-radius: 6px;
 font-weight: bold;
 color: white;
}
.react-calendar__tile--active:enabled:hover,
.react-calendar__tile--active:enabled:focus {
 background: #6f48eb;
 color: white;
}
.react-calendar--selectRange .react-calendar__tile--hover {
 background-color: #f8f8fa;
}
.react-calendar__tile--range {
 background: #f8f8fa;
 color: #6f48eb;
 border-radius: 0;
}
.react-calendar__tile--rangeStart {
 border-top-right-radius: 0;
 border-bottom-right-radius: 0;
 border-top-left-radius: 6px;
 border-bottom-left-radius: 6px;
 background: #6f48eb;
 color: white;
}
.react-calendar__tile--rangeEnd {
 border-top-left-radius: 0;
 border-bottom-left-radius: 0;
 border-top-right-radius: 6px;
 border-bottom-right-radius: 6px;
 background: #6f48eb;
 color: white;
}

This is the custom styling I am trying to add. I can also completely delete all of Calendar.css file and leave it blank but the first picture shown above^^ will still show like that I don't know if it makes a difference but I am also using tailwind css with this program.

// App.js

import { useState } from "react";
import Calendar from "react-calendar";
import "react-calendar/dist/Calendar.css";

function cal() {
  const [date, setDate] = useState(new Date());

  return (
    <div className="app">
      <h1 className="text-center">React Calendar</h1>
      <div className="calendar-container">
        <Calendar onChange={setDate} value={date} />
      </div>
      <p className="text-center">
        <span className="bold">Selected Date:</span> {date.toDateString()}
      </p>
    </div>
  );
}

export default cal;

This is where I am trying to create the calendar

Answer 1

You can add !important to the properties to force the overwrite, for example:

.react-calendar__tile--rangeEnd {
  border-top-left-radius: 0 !important;
  border-bottom-left-radius: 0 !important;
  border-top-right-radius: 6px !important;
  border-bottom-right-radius: 6px !important;
  background: #6f48eb !important;
  color: white !important;
}