Fixes exact matches to breakpoints returning both devices, i.e 768px screens showing both mobile and tablet. Fixes #527

src/collections/grid.less

@@ -110,7 +110,7 @@ body > .ui.grid {
   margin-right: 0%;
 }
 
-@media only screen and (max-width : 992px) {
+@media only screen and (max-width : 991px) {
   .ui.page.grid {
     padding: 0% 4%;
   }
@@ -515,7 +515,7 @@ body > .ui.grid {
 -----------------------*/
 
 /* Mobile Only */
-@media only screen and (max-width : 768px) {
+@media only screen and (max-width : 767px) {
   .ui.mobile.only.grid,
   .ui.grid > .mobile.only.row {
     display: block !important;
@@ -551,7 +551,7 @@ body > .ui.grid {
   }
 }
 /* Tablet Only */
-@media only screen and (min-width : 768px) and (max-width : 992px) {
+@media only screen and (min-width : 768px) and (max-width : 991px) {
   .ui.tablet.only.grid,
   .ui.grid > .tablet.only.row {
     display: block !important;
@@ -578,7 +578,7 @@ body > .ui.grid {
     display: table-cell !important;
   }
 }
-@media only screen and (max-width : 768px), (min-width: 992px) {
+@media only screen and (max-width : 767px), (min-width: 992px) {
   .ui.tablet.only.grid,
   .ui.grid > .tablet.only.row,
   .ui.grid > .tablet.only.column,
@@ -614,7 +614,7 @@ body > .ui.grid {
     display: table-cell !important;
   }
 }
-@media only screen and (max-width : 992px) {
+@media only screen and (max-width : 991px) {
   .ui.computer.only.grid,
   .ui.grid > .computer.only.row,
   .ui.grid > .computer.only.column,
@@ -629,7 +629,7 @@ body > .ui.grid {
 --------------------*/
 
 /* Mobily Only */
-@media only screen and (max-width : 768px) {
+@media only screen and (max-width : 767px) {
   .ui.two.column.doubling.grid > .row > .column,
   .ui.two.column.doubling.grid > .column,
   .ui.grid > .two.column.doubling.row > .column {
@@ -693,7 +693,7 @@ body > .ui.grid {
 }
 
 /* Tablet Only */
-@media only screen and (min-width : 768px) and (max-width : 992px) {
+@media only screen and (min-width : 768px) and (max-width : 991px) {
   .ui.two.column.doubling.grid > .row > .column,
   .ui.two.column.doubling.grid > .column,
   .ui.grid > .two.column.doubling.row > .column {
@@ -757,10 +757,10 @@ body > .ui.grid {
 }
 
 /*-------------------
-       Stackable
+      Stackable
 --------------------*/
 
-@media only screen and (max-width : 768px) {
+@media only screen and (max-width : 767px) {
   .ui.stackable.grid {
     display: block !important;
     padding: 0em;