fix: 비일관적인 breakpoint 정정

- md가 아니라 lg를 기준으로 잡아야 함
- lg의 기준 breakpoint를 940으로 변경
- is100pxMode의 기준 역시 lg breakpoint와 일치

hwe/scss/common/break_500px.scss

@@ -3,7 +3,7 @@
 
 $container-max-widths: (
     md: 500px,
-    lg: 1020px,
+    lg: 1000px,
     xl: 1140px,
     xxl: 1320px
   );
@@ -11,8 +11,8 @@ $container-max-widths: (
 $grid-breakpoints: (
   xs: 0,
   sm: 520px,
-  md: 900px,
-  lg: 992px,
+  md: 760px,
+  lg: 940px,
   xl: 1200px,
   xxl: 1400px
 );
@@ -24,7 +24,7 @@ $grid-breakpoints: (
 }
 
 @mixin media-1000px{
-  @media (min-width: map-get($grid-breakpoints, 'md')) {
+  @media (min-width: map-get($grid-breakpoints, 'lg')) {
     @content;
   }
 
@@ -36,7 +36,7 @@ $grid-breakpoints: (
 }
 
 @mixin media-500px{
-  @media (max-width: calc(map-get($grid-breakpoints, 'md') - .02px)) {
+  @media (max-width: calc(map-get($grid-breakpoints, 'lg') - .02px)) {
     @content;
   }
 }