Bootstrap5のグリッドシステム v4からの変更点

/* Extra small devices: Phones (<576px) */
@media (max-width: 575px) {}
 
/* Small devices: Phablet (≥576px) */
@media (min-width: 576px) and (max-width: 767px) {}
 
/* Medium devices: Tablets (≥768px) */
@media (min-width: 768px) and (max-width: 991px) {}
 
/* Large devices: laptop (≥992px) */
@media (min-width: 992px) and (max-width: 1199px) {}
 
/* Extra Large devices: Desktops (≥1200px) */
@media (min-width: 1200px) {}

/* Small devices (landscape phones, 576px and up) */
@media (min-width: 576px) {}

/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {}

/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {}

/* X-Large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {}

/* XX-Large devices (larger desktops, 1400px and up) */
@media (min-width: 1400px) {}