diff --git a/lib/Autocomplete.js b/lib/Autocomplete.js
index 6f7efaa5..8b6da598 100644
--- a/lib/Autocomplete.js
+++ b/lib/Autocomplete.js
@@ -30,9 +30,9 @@ let Autocomplete = React.createClass({
         background: 'rgba(255, 255, 255, 0.9)',
         padding: '2px 0',
         fontSize: '90%',
-        position: 'fixed',
+        position: 'absolute',
         overflow: 'auto',
-        maxHeight: '50%', // TODO: don't cheat, let it flow to the bottom
+        maxHeight: Math.max(document.documentElement.clientHeight, window.innerHeight || 0)/2 +'px',
       }
     }
   },
@@ -217,12 +217,9 @@ let Autocomplete = React.createClass({
     var node = this.refs.input
     var rect = node.getBoundingClientRect()
     var computedStyle = getComputedStyle(node)
-    var marginBottom = parseInt(computedStyle.marginBottom, 10)
     var marginLeft = parseInt(computedStyle.marginLeft, 10)
     var marginRight = parseInt(computedStyle.marginRight, 10)
     this.setState({
-      menuTop: rect.bottom + marginBottom,
-      menuLeft: rect.left + marginLeft,
       menuWidth: rect.width + marginLeft + marginRight
     })
   },
@@ -298,7 +295,7 @@ let Autocomplete = React.createClass({
       })
     }
     return (
-      <div style={{display: 'inline-block'}}>
+      <div style={{display: 'inline-block', position: 'relative'}}>
         <input
           {...this.props.inputProps}
           role="combobox"