diff --git a/src/App.tsx b/src/App.tsx
index e916cf8..d688bd5 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -2,12 +2,13 @@ import { useCallback, useEffect, useState } from 'react';
 import tw from 'twin.macro';
 import { invoke } from '@tauri-apps/api/tauri';
 import './App.css';
-import clsx from 'clsx';
 import { Configurator } from './configurator/configurator';
 import { ButtonSwitch } from './commons/components/button';
 
 type Mode = 'Flowing' | 'Follow' | null;
 
+localStorage.setItem('debug', '*');
+
 function App() {
   const [screenshots, setScreenshots] = useState<string[]>([]);
   const [ledStripColors, setLedStripColors] = useState<string[]>([]);
diff --git a/src/configurator/components/completed-led-strip.tsx b/src/configurator/components/completed-led-strip.tsx
index 28f52a0..cc0f9a6 100644
--- a/src/configurator/components/completed-led-strip.tsx
+++ b/src/configurator/components/completed-led-strip.tsx
@@ -1,26 +1,43 @@
-import { isNil, splitEvery } from 'ramda';
-import { FC, useMemo } from 'react';
+import debug from 'debug';
+import { isNil, lensPath, set, splitEvery, update } from 'ramda';
+import {
+  createRef,
+  FC,
+  Fragment,
+  MouseEventHandler,
+  ReactEventHandler,
+  ReactNode,
+  RefObject,
+  useCallback,
+  useEffect,
+  useMemo,
+  useRef,
+  useState,
+} from 'react';
 import tw, { css, styled } from 'twin.macro';
-import { borders } from '../../constants/border';
-import { DisplayConfig } from '../models/display-config';
+import { Borders, borders } from '../../constants/border';
+import { useLedCount } from '../contents/led-count';
+import { DisplayConfig, LedStripConfigOfBorders } from '../models/display-config';
 import { LedStripConfig } from '../models/led-strip-config';
+import { PixelRgb } from '../models/pixel-rgb';
 import { ScreenshotDto } from '../models/screenshot.dto';
-import { LedStrip } from './led-strip';
 import { StyledPixel } from './styled-pixel';
 
+const logger = debug('app:completed-led-strip');
+
 interface CompletedLedStripProps {
   screenshots: ScreenshotDto[];
   onDisplayConfigChange?: (value: DisplayConfig) => void;
 }
 
 type BorderLedStrip = {
-  pixels: [number, number, number][];
+  pixels: PixelRgb[];
   config: LedStripConfig | null;
 };
 
 const StyledContainer = styled.section(
   ({ rows, columns }: { rows: number; columns: number }) => [
-    tw`grid m-4 pb-2`,
+    tw`grid m-4 pb-2 items-center justify-items-center select-none`,
     css`
       grid-template-columns: repeat(${columns}, 1fr);
       grid-template-rows: auto repeat(${rows}, 1fr);
@@ -31,6 +48,7 @@ const StyledCompletedContainer = styled.section(
   tw`dark:bg-transparent shadow-xl border-gray-500 border rounded-full flex flex-wrap justify-around items-center mb-2`,
   css`
     grid-column: 1 / -1;
+    justify-self: stretch;
   `,
 );
 
@@ -41,7 +59,7 @@ export const CompletedLedStrip: FC<CompletedLedStripProps> = ({
   const borderLedStrips: BorderLedStrip[] = useMemo(() => {
     return screenshots.flatMap((ss) =>
       borders.map((b) => ({
-        pixels: splitEvery(3, Array.from(ss.colors[b])) as [number, number, number][],
+        pixels: splitEvery(3, Array.from(ss.colors[b])) as PixelRgb[],
         config: ss.config.led_strip_of_borders[b],
       })),
     );
@@ -51,9 +69,18 @@ export const CompletedLedStrip: FC<CompletedLedStripProps> = ({
     [borderLedStrips],
   );
 
+  const { setLedCount } = useLedCount();
+  // setLedCount for context
+  useEffect(() => {
+    setLedCount(ledCount);
+  }, [ledCount, setLedCount]);
+
+  const [overrideBorderLedStrips, setOverrideBorderLedStrips] =
+    useState<BorderLedStrip[]>();
+
   const completedPixels = useMemo(() => {
-    const completed: [number, number, number][] = new Array(ledCount).fill([0, 0, 0]);
-    borderLedStrips.forEach(({ pixels, config }) => {
+    const completed: PixelRgb[] = new Array(ledCount).fill([0, 0, 0]);
+    (overrideBorderLedStrips ?? borderLedStrips).forEach(({ pixels, config }) => {
       if (isNil(config)) {
         return;
       }
@@ -68,21 +95,45 @@ export const CompletedLedStrip: FC<CompletedLedStripProps> = ({
       }
     });
 
-    return completed.map((color) => <StyledPixel rgb={color} />);
-  }, [ledCount, borderLedStrips]);
+    return completed.map((color, i) => <StyledPixel rgb={color} key={i} />);
+  }, [ledCount, borderLedStrips, overrideBorderLedStrips]);
 
   const strips = useMemo(() => {
-    return borderLedStrips.map(({ config, pixels }, index) => (
-      <LedStrip
-        key={index}
-        colors={Uint8Array.from(pixels.flat())}
-        config={config}
-        css={css`
-          grid-column-start: ${(config?.global_start_position ?? 0) + 1};
-          grid-column-end: ${(config?.global_end_position ?? 0) + 1};
-        `}
-      />
-    ));
+    return (overrideBorderLedStrips ?? borderLedStrips).map(({ config, pixels }, index) =>
+      config ? (
+        <DraggableStrip
+          key={index}
+          {...{ config, pixels, index: index + 1 }}
+          onConfigChange={(c) => {
+            setOverrideBorderLedStrips(
+              update(index, { config: c, pixels }, borderLedStrips),
+            );
+          }}
+          onConfigFinish={(c) => {
+            const indexOfDisplay = Math.round(index / borders.length);
+            const xLens = lensPath<LedStripConfigOfBorders, Borders>([
+              borders[index % borders.length],
+            ]);
+            const displayConfig: DisplayConfig = {
+              ...screenshots[indexOfDisplay].config,
+              led_strip_of_borders: set(
+                xLens,
+                c,
+                screenshots[indexOfDisplay].config.led_strip_of_borders,
+              ),
+            };
+            logger('Change DisplayConfig. %o', displayConfig);
+            onDisplayConfigChange?.(displayConfig);
+          }}
+        />
+      ) : (
+        <div key={index} />
+      ),
+    );
+  }, [borderLedStrips, overrideBorderLedStrips]);
+
+  useEffect(() => {
+    setOverrideBorderLedStrips(undefined);
   }, [borderLedStrips]);
   return (
     <StyledContainer rows={screenshots.length * borders.length} columns={ledCount}>
@@ -91,3 +142,173 @@ export const CompletedLedStrip: FC<CompletedLedStripProps> = ({
     </StyledContainer>
   );
 };
+
+interface DraggableStripProp {
+  config: LedStripConfig;
+  pixels: PixelRgb[];
+  index: number;
+  onConfigChange?: (config: LedStripConfig) => void;
+  onConfigFinish?: (config: LedStripConfig) => void;
+}
+
+const DraggableStrip: FC<DraggableStripProp> = ({
+  config,
+  pixels,
+  index,
+  onConfigChange,
+  onConfigFinish,
+}) => {
+  const ledItems = pixels.map((rgb, i) => (
+    <StyledPixel
+      key={i}
+      rgb={rgb}
+      css={css`
+        grid-column: ${(config?.global_start_position ?? 0) + i + 1} / span 1;
+        grid-row-start: ${index + 1};
+        pointer-events: none;
+      `}
+    />
+  ));
+
+  const { ledCount } = useLedCount();
+
+  const startXRef = useRef(0);
+  const currentXRef = useRef(0);
+  const configRef = useRef<LedStripConfig>();
+  // const currentDiffRef = useRef(0);
+  const [currentDiff, setCurrentDiff] = useState(0);
+  const isDragRef = useRef(false);
+  const handleMouseMoveRef = useRef<(ev: MouseEvent) => void>();
+  const [boxTranslateX, setBoxTranslateX] = useState(0);
+
+  const [placeholders, placeholderRefs]: [ReactNode[], RefObject<HTMLSpanElement>[]] =
+    useMemo(
+      () =>
+        new Array(ledCount)
+          .fill(undefined)
+          .map((_, i) => {
+            const ref = createRef<HTMLSpanElement>();
+            const n = (
+              <span
+                ref={ref}
+                key={i}
+                tw="opacity-30 bg-red-500 h-full w-full border border-yellow-400"
+                css={css`
+                  grid-column-start: ${i + 1};
+                  grid-row-start: ${index + 1};
+                `}
+              />
+            );
+            return [n, ref] as [ReactNode, RefObject<HTMLSpanElement>];
+          })
+          .reduce(
+            ([nList, refList], [n, ref]) => [
+              [...nList, n],
+              [...refList, ref],
+            ],
+            [[], []] as [ReactNode[], RefObject<HTMLSpanElement>[]],
+          ),
+      [ledCount],
+    );
+
+  const handleMouseDown: MouseEventHandler<HTMLDivElement> = useCallback(
+    (ev) => {
+      startXRef.current = ev.pageX;
+      ev.currentTarget.requestPointerLock();
+      isDragRef.current = true;
+
+      const placeholderPositions = placeholderRefs.map((it) => {
+        if (!it.current) {
+          return [0, 0];
+        }
+        const viewportOffset = it.current.getBoundingClientRect();
+        return [viewportOffset.left, viewportOffset.right] as [number, number];
+      });
+
+      logger('placeholderPositions: %o', placeholderPositions);
+
+      // set init position
+      const initPos = placeholderPositions.findIndex(
+        ([l, r]) => l <= ev.pageX && r >= ev.pageX,
+      );
+      setCurrentDiff(initPos);
+      let prevMatch = 0;
+
+      if (handleMouseMoveRef.current) {
+        document.body.removeEventListener('mousemove', handleMouseMoveRef.current);
+      }
+      handleMouseMoveRef.current = (ev) => {
+        if (!isDragRef.current) {
+          return;
+        }
+        currentXRef.current = ev.pageX;
+        setBoxTranslateX(currentXRef.current - startXRef.current);
+        const match = placeholderPositions.findIndex(
+          ([l, r]) => l <= currentXRef.current && r >= currentXRef.current,
+        );
+        if (match === -1) {
+          return;
+        }
+
+        if (match === prevMatch) {
+          return;
+        }
+        prevMatch = match;
+
+        const diff = match - initPos;
+        const newValue: LedStripConfig = {
+          ...config,
+          global_start_position: config.global_start_position + diff,
+          global_end_position: config.global_end_position + diff,
+        };
+        configRef.current = newValue;
+        logger('change config. new: $o', newValue);
+        onConfigChange?.(newValue);
+      };
+      document.body.addEventListener('mousemove', handleMouseMoveRef.current);
+    },
+    [placeholderRefs],
+  );
+
+  // move event.
+  useEffect(() => {
+    const handleMouseUp = (ev: MouseEvent) => {
+      startXRef.current = 0;
+      isDragRef.current = false;
+      if (configRef.current) {
+        onConfigFinish?.(configRef.current);
+      }
+      document.exitPointerLock();
+      if (handleMouseMoveRef.current) {
+        document.body.removeEventListener('mousemove', handleMouseMoveRef.current);
+      }
+    };
+    document.body.addEventListener('mouseup', handleMouseUp);
+    return () => {
+      document.body.removeEventListener('mouseup', handleMouseUp);
+    };
+  }, []);
+  // reset translateX when config updated.
+  useEffect(() => {
+    startXRef.current = currentXRef.current;
+    setCurrentDiff(0);
+  }, [config]);
+
+  return (
+    <Fragment>
+      {placeholders}
+      {ledItems}
+      <div
+        tw="border border-gray-700 h-3 w-full rounded-full"
+        css={css`
+          grid-column-start: ${(config?.global_start_position ?? 0) + 1 - currentDiff};
+          grid-column-end: ${(config?.global_end_position ?? 0) + 1 - currentDiff};
+          grid-row-start: ${index + 1};
+          cursor: ew-resize;
+          transform: translateX(${boxTranslateX}px);
+        `}
+        onMouseDown={handleMouseDown}
+      ></div>
+    </Fragment>
+  );
+};
diff --git a/src/configurator/configurator.tsx b/src/configurator/configurator.tsx
index ec5ebc2..882d274 100644
--- a/src/configurator/configurator.tsx
+++ b/src/configurator/configurator.tsx
@@ -11,6 +11,7 @@ import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
 import { faSpinner } from '@fortawesome/free-solid-svg-icons';
 import { update } from 'ramda';
 import { CompletedLedStrip } from './components/completed-led-strip';
+import { LedCountProvider } from './contents/led-count';
 
 const getPickerConfig = () => invoke<PickerConfiguration>('get_picker_config');
 const getScreenshotOfDisplays = () =>
@@ -31,7 +32,7 @@ const StyledConfiguratorContainer = styled.section(tw`flex flex-col items-stretc
 
 const StyledDisplayContainer = styled.section(tw`overflow-auto`);
 
-export const Configurator: FC = () => {
+const ConfiguratorInner: FC = () => {
   const { loading: pendingPickerConfig, result: savedPickerConfig } = useAsync(
     getPickerConfig,
     [],
@@ -96,7 +97,10 @@ export const Configurator: FC = () => {
 
   return (
     <StyledConfiguratorContainer>
-      <CompletedLedStrip screenshots={screenshotOfDisplays} />
+      <CompletedLedStrip
+        screenshots={screenshotOfDisplays}
+        onDisplayConfigChange={onDisplayConfigChange}
+      />
       <StyledDisplayContainer>{displays}</StyledDisplayContainer>;
       <Snackbar open={pendingGetLedColorsByConfig} autoHideDuration={3000}>
         <Alert icon={<FontAwesomeIcon icon={faSpinner} />} sx={{ width: '100%' }}>
@@ -106,3 +110,11 @@ export const Configurator: FC = () => {
     </StyledConfiguratorContainer>
   );
 };
+
+export const Configurator = () => {
+  return (
+    <LedCountProvider>
+      <ConfiguratorInner />
+    </LedCountProvider>
+  );
+};
diff --git a/src/configurator/contents/led-count.tsx b/src/configurator/contents/led-count.tsx
new file mode 100644
index 0000000..ec3ba4a
--- /dev/null
+++ b/src/configurator/contents/led-count.tsx
@@ -0,0 +1,25 @@
+import {
+  createContext,
+  Dispatch,
+  FC,
+  ReactNode,
+  SetStateAction,
+  useContext,
+  useState,
+} from 'react';
+
+interface LedCountContext {
+  ledCount: number;
+  setLedCount: Dispatch<SetStateAction<number>>;
+}
+
+const Context = createContext<LedCountContext>(undefined as any);
+
+export const LedCountProvider: FC<{ children: ReactNode }> = ({ children }) => {
+  const [ledCount, setLedCount] = useState(0);
+  return (
+    <Context.Provider value={{ ledCount, setLedCount }}>{children}</Context.Provider>
+  );
+};
+
+export const useLedCount = () => useContext(Context);
diff --git a/src/configurator/models/pixel-rgb.ts b/src/configurator/models/pixel-rgb.ts
new file mode 100644
index 0000000..2229ef0
--- /dev/null
+++ b/src/configurator/models/pixel-rgb.ts
@@ -0,0 +1 @@
+export type PixelRgb = [number, number, number];
\ No newline at end of file