styles: improve responsiveness

static/styles.css

@@ -8,6 +8,10 @@ body {
   line-height: 1.8rem;
 }
 
+.h-entry img {
+  max-width: 100%;
+}
+
 nav {
   padding: 1em;
   width: 15em;
@@ -39,9 +43,6 @@ main {
 }
 
 @media only screen
-  and (min-device-width: 375px)
-  and (max-device-width: 812px)
-  and (-webkit-min-device-pixel-ratio: 3)
   and (orientation: portrait) {
   body {
     flex-direction: column;