   dup elevator>> over thumb>> add-gadget
   @center grid-add* ;
 
-: <left-button> ( -- button )
-    { 0 1 } arrow-left -1 <slide-button> ;
-
-: <right-button> ( -- button )
-    { 0 1 } arrow-right 1 <slide-button> ;
-
-: <up-button> ( -- button )
-    { 1 0 } arrow-up -1 <slide-button> ;
-
-: <down-button> ( -- button )
-    { 1 0 } arrow-down 1 <slide-button> ;
+: <left-button>  ( -- button ) { 0 1 } arrow-left -1 <slide-button> ;
+: <right-button> ( -- button ) { 0 1 } arrow-right 1 <slide-button> ;
+: <up-button>    ( -- button ) { 1 0 } arrow-up   -1 <slide-button> ;
+: <down-button>  ( -- button ) { 1 0 } arrow-down  1 <slide-button> ;
 
 : <slider> ( range orientation -- slider )
     slider new-frame

    { T{ button-down } [ elevator-click ] }
} set-gestures

: elevator-theme ( elevator -- )
    lowered-gradient swap set-gadget-interior ;

: <elevator> ( vector -- elevator )
    elevator new-gadget
    [ set-gadget-orientation ] keep
    dup elevator-theme ;

: (layout-thumb) ( slider n -- n thumb )
    over gadget-orientation n*v swap slider-thumb ;

        t >>root?
    thumb-theme ;

: slide-by ( amount slider -- ) gadget-model move-by ;

: slide-by-page ( amount slider -- ) gadget-model move-by-page ;

: compute-direction ( elevator -- -1/1 )
    dup find-slider swap hand-click-rel
