From d4b07f47aba8295950d28c1d95f519752510836b Mon Sep 17 00:00:00 2001
From: Dmytro Yarmak <dmytroyarmak@gmail.com>
Date: Fri, 7 Dec 2018 14:08:32 +0200
Subject: [PATCH] fix(learn): implemented curriculum layout for mobile devices
 (#17467)

remove useless changes
---
 client/src/components/layouts/layout.css      |   2 +-
 client/src/pages/learn.css                    |   7 +
 .../src/templates/Challenges/classic/Show.js  | 281 +++++++++++++-----
 .../templates/Challenges/classic/classic.css  |  27 +-
 .../Challenges/components/CompletionModal.js  |   2 +-
 .../Challenges/components/HelpModal.js        |   4 +-
 .../Challenges/components/Preview.js          |  24 +-
 .../Challenges/components/Side-Panel.js       |   6 +-
 .../Challenges/components/Tool-Panel.js       |  16 +-
 .../components/completion-modal.css           |   6 +
 .../Challenges/components/help-modal.css      |   5 +
 .../Challenges/components/preview.css         |   7 +
 .../Challenges/components/reset-modal.css     |   8 +-
 .../Challenges/components/tool-panel.css      |  14 +
 .../redux/execute-challenge-epic.js           |   7 +-
 .../src/templates/Challenges/redux/index.js   |  16 +
 client/src/templates/Introduction/Intro.js    |  52 ++--
 client/src/templates/Introduction/intro.css   |   6 +
 18 files changed, 382 insertions(+), 108 deletions(-)
 create mode 100644 client/src/templates/Challenges/components/help-modal.css

diff --git a/client/src/components/layouts/layout.css b/client/src/components/layouts/layout.css
index 398be36a0b..2868e1bee0 100644
--- a/client/src/components/layouts/layout.css
+++ b/client/src/components/layouts/layout.css
@@ -624,4 +624,4 @@ pre tt:after {
 }
 .default-layout {
   margin-top: 38px;
-}
\ No newline at end of file
+}
diff --git a/client/src/pages/learn.css b/client/src/pages/learn.css
index 6fd8f19082..b057415234 100644
--- a/client/src/pages/learn.css
+++ b/client/src/pages/learn.css
@@ -25,6 +25,13 @@
   padding: 5px 10px 5px 10px;
 }
 
+@media screen, (max-width: 767px) {
+  #learn-app-wrapper {
+    right: -2em;
+    padding: 2px 0 0 0;
+  }
+}
+
 .reflex-layout.reflex-container.vertical {
   width: 100%;
   margin: 0 18px;
diff --git a/client/src/templates/Challenges/classic/Show.js b/client/src/templates/Challenges/classic/Show.js
index 6bd2012ec1..3aa39fa723 100644
--- a/client/src/templates/Challenges/classic/Show.js
+++ b/client/src/templates/Challenges/classic/Show.js
@@ -1,4 +1,4 @@
-import React, { Component } from 'react';
+import React, { Component, Fragment } from 'react';
 import PropTypes from 'prop-types';
 import { bindActionCreators } from 'redux';
 import { createSelector } from 'reselect';
@@ -7,6 +7,8 @@ import Helmet from 'react-helmet';
 import { ReflexContainer, ReflexSplitter, ReflexElement } from 'react-reflex';
 import { graphql } from 'gatsby';
 import { first } from 'lodash';
+import { Tabs, TabPane } from '@freecodecamp/react-bootstrap';
+import Media from 'react-media';
 
 import LearnLayout from '../../../components/layouts/Learn';
 import Editor from './Editor';
@@ -17,6 +19,7 @@ import CompletionModal from '../components/CompletionModal';
 import HelpModal from '../components/HelpModal';
 import VideoModal from '../components/VideoModal';
 import ResetModal from '../components/ResetModal';
+import ToolPanel from '../components/Tool-Panel';
 
 import { randomCompliment } from '../utils/get-words';
 import { createGuideUrl } from '../utils';
@@ -27,11 +30,13 @@ import {
   createFiles,
   challengeFilesSelector,
   challengeTestsSelector,
+  currentTabSelector,
   initTests,
   updateChallengeMeta,
   challengeMounted,
   updateSuccessMessage,
-  consoleOutputSelector
+  consoleOutputSelector,
+  moveToTab
 } from '../redux';
 
 import './classic.css';
@@ -43,16 +48,19 @@ const mapStateToProps = createSelector(
   challengeFilesSelector,
   challengeTestsSelector,
   consoleOutputSelector,
-  (files, tests, output) => ({
+  currentTabSelector,
+  (files, tests, output, currentTab) => ({
     files,
     tests,
-    output
+    output,
+    currentTab
   })
 );
 
 const mapDispatchToProps = dispatch =>
   bindActionCreators(
     {
+      moveToTab,
       createFiles,
       initTests,
       updateChallengeMeta,
@@ -65,6 +73,7 @@ const mapDispatchToProps = dispatch =>
 const propTypes = {
   challengeMounted: PropTypes.func.isRequired,
   createFiles: PropTypes.func.isRequired,
+  currentTab: PropTypes.number,
   data: PropTypes.shape({
     challengeNode: ChallengeNode
   }),
@@ -72,6 +81,7 @@ const propTypes = {
     key: PropTypes.string
   }),
   initTests: PropTypes.func.isRequired,
+  moveToTab: PropTypes.func.isRequired,
   output: PropTypes.string,
   pageContext: PropTypes.shape({
     challengeMeta: PropTypes.shape({
@@ -88,6 +98,8 @@ const propTypes = {
   updateSuccessMessage: PropTypes.func.isRequired
 };
 
+const MAX_MOBILE_WIDTH = 767;
+
 class ShowClassic extends Component {
   constructor() {
     super();
@@ -101,7 +113,6 @@ class ShowClassic extends Component {
       resizing: false
     };
   }
-
   onResize() {
     this.setState({ resizing: true });
   }
@@ -169,88 +180,222 @@ class ShowClassic extends Component {
     }
   }
 
-  render() {
+  getBlockNameTitle() {
     const {
       data: {
         challengeNode: {
-          challengeType,
-          fields: { blockName, slug },
-          title,
+          fields: { blockName },
+          title
+        }
+      }
+    } = this.props;
+    return `${blockName}: ${title}`;
+  }
+
+  getGuideUrl() {
+    const {
+      data: {
+        challengeNode: {
+          fields: { slug }
+        }
+      }
+    } = this.props;
+    return createGuideUrl(slug);
+  }
+
+  getChallengeFile() {
+    const { files } = this.props;
+    return first(Object.keys(files).map(key => files[key]));
+  }
+
+  hasPreview() {
+    const {
+      data: {
+        challengeNode: {
+          challengeType
+        }
+      }
+    } = this.props;
+    return (
+      challengeType === challengeTypes.html ||
+      challengeType === challengeTypes.modern
+    );
+  }
+
+  renderInstructionsPanel({ showToolPanel }) {
+    const {
+      data: {
+        challengeNode: {
+          fields: { blockName },
           description,
           instructions,
           videoUrl
         }
-      },
-      files,
-      output
+      }
     } = this.props;
+    return (
+      <SidePanel
+        className='full-height'
+        description={description}
+        guideUrl={this.getGuideUrl()}
+        instructions={instructions}
+        section={dasherize(blockName)}
+        showToolPanel={showToolPanel}
+        title={this.getBlockNameTitle()}
+        videoUrl={videoUrl}
+      />
+    );
+  }
+
+  renderEditor() {
+    const { files } = this.props;
     const challengeFile = first(Object.keys(files).map(key => files[key]));
-    const editors = challengeFile && (
-      <ReflexContainer key={challengeFile.key} orientation='horizontal'>
-        <ReflexElement
-          flex={1}
-          propagateDimensions={true}
-          renderOnResize={true}
-          renderOnResizeRate={20}
-          {...this.resizeProps}
-          >
-          <Editor {...challengeFile} fileKey={challengeFile.key} />
-        </ReflexElement>
-        <ReflexSplitter propagate={true} {...this.resizeProps} />
-        <ReflexElement
-          flex={0.25}
-          propagateDimensions={true}
-          renderOnResize={true}
-          renderOnResizeRate={20}
-          {...this.resizeProps}
-          >
-          <Output
+    return challengeFile && (
+      <Editor {...challengeFile} fileKey={challengeFile.key} />
+    );
+  }
+
+  renderTestOutput() {
+    const { output } = this.props;
+    return (
+      <Output
             defaultOutput={`
 /**
 * Your test output will go here.
 */
 `}
-            output={decodeHTMLEntities(output)}
-          />
+        output={decodeHTMLEntities(output)}
+      />
+    );
+  }
+
+  renderPreview() {
+    return (
+      <Preview
+        className='full-height'
+        disableIframe={this.state.resizing}
+      />
+    );
+  }
+
+  renderDesktopLayout() {
+    const challengeFile = this.getChallengeFile();
+    return (
+      <ReflexContainer orientation='vertical'>
+        <ReflexElement flex={1} {...this.resizeProps}>
+          {this.renderInstructionsPanel({ showToolPanel: true })}
         </ReflexElement>
+        <ReflexSplitter propagate={true} {...this.resizeProps} />
+        <ReflexElement flex={1} {...this.resizeProps}>
+          {challengeFile && (
+            <ReflexContainer key={challengeFile.key} orientation='horizontal'>
+              <ReflexElement
+                flex={1}
+                propagateDimensions={true}
+                renderOnResize={true}
+                renderOnResizeRate={20}
+                {...this.resizeProps}
+                >
+                {this.renderEditor()}
+              </ReflexElement>
+              <ReflexSplitter propagate={true} {...this.resizeProps} />
+              <ReflexElement
+                flex={0.25}
+                propagateDimensions={true}
+                renderOnResize={true}
+                renderOnResizeRate={20}
+                {...this.resizeProps}
+                >
+                {this.renderTestOutput()}
+              </ReflexElement>
+            </ReflexContainer>
+          )}
+        </ReflexElement>
+        {this.hasPreview() && (
+          <Fragment>
+            <ReflexSplitter propagate={true} {...this.resizeProps} />
+            <ReflexElement flex={0.7} {...this.resizeProps}>
+              {this.renderPreview()}
+            </ReflexElement>
+          </Fragment>
+        )}
       </ReflexContainer>
     );
-    const showPreview =
-      challengeType === challengeTypes.html ||
-      challengeType === challengeTypes.modern;
-    const blockNameTitle = `${blockName}: ${title}`;
+  }
+
+  renderMobileLayout() {
+    const {
+      data: {
+        challengeNode: {
+          videoUrl
+        }
+      },
+      currentTab,
+      moveToTab
+    } = this.props;
+
+    const editorTabPaneProps = {
+      mountOnEnter: true,
+      unmountOnExit: true
+    };
+
+    return (
+      <Fragment>
+        <Tabs
+          activeKey={currentTab}
+          defaultActiveKey={1}
+          id='challege-page-tabs'
+          onSelect={(key) => moveToTab(key)}
+          >
+          <TabPane eventKey={1} title='Instructions'>
+            { this.renderInstructionsPanel({ showToolPanel: false }) }
+          </TabPane>
+          <TabPane eventKey={2} title='Code' {...editorTabPaneProps}>
+            <div className='challege-edittor-wrapper'>
+              {this.renderEditor()}
+            </div>
+          </TabPane>
+          <TabPane eventKey={3} title='Tests' {...editorTabPaneProps}>
+            <div className='challege-edittor-wrapper'>
+              {this.renderTestOutput()}
+            </div>
+          </TabPane>
+          {this.hasPreview() && (
+            <TabPane eventKey={4} title='Preview'>
+              {this.renderPreview()}
+            </TabPane>
+          )}
+        </Tabs>
+        <ToolPanel
+          guideUrl={this.getGuideUrl()}
+          isMobile={true}
+          videoUrl={videoUrl}
+        />
+      </Fragment>
+    );
+  }
+
+  render() {
+    const {
+      data: {
+        challengeNode: {
+          videoUrl
+        }
+      }
+    } = this.props;
+
     return (
       <LearnLayout>
-        <Helmet title={`Learn ${blockNameTitle} | freeCodeCamp.org`} />
-        <ReflexContainer orientation='vertical'>
-          <ReflexElement flex={1} {...this.resizeProps}>
-            <SidePanel
-              className='full-height'
-              description={description}
-              guideUrl={createGuideUrl(slug)}
-              instructions={instructions}
-              section={dasherize(blockName)}
-              title={blockNameTitle}
-              videoUrl={videoUrl}
-            />
-          </ReflexElement>
-          <ReflexSplitter propagate={true} {...this.resizeProps} />
-          <ReflexElement flex={1} {...this.resizeProps}>
-            {editors}
-          </ReflexElement>
-          {showPreview && (
-            <ReflexSplitter propagate={true} {...this.resizeProps} />
-          )}
-          {showPreview ? (
-            <ReflexElement flex={0.7} {...this.resizeProps}>
-              <Preview
-                className='full-height'
-                disableIframe={this.state.resizing}
-              />
-            </ReflexElement>
-          ) : null}
-        </ReflexContainer>
-
+        <Helmet
+          title={`Learn ${this.getBlockNameTitle()} | freeCodeCamp.org`}
+        />
+        <Media query={{ maxWidth: MAX_MOBILE_WIDTH }}>
+          {matches =>
+            matches
+              ? this.renderMobileLayout()
+              : this.renderDesktopLayout()
+          }
+        </Media>
         <CompletionModal />
         <HelpModal />
         <VideoModal videoUrl={videoUrl} />
diff --git a/client/src/templates/Challenges/classic/classic.css b/client/src/templates/Challenges/classic/classic.css
index ef40a1a489..6d38590827 100644
--- a/client/src/templates/Challenges/classic/classic.css
+++ b/client/src/templates/Challenges/classic/classic.css
@@ -13,6 +13,12 @@
   overflow-y: auto;
 }
 
+@media screen, (max-width: 767px) {
+  .instructions-panel {
+    height: calc(100vh - 112px);
+  }
+}
+
 .react-monaco-editor-container {
   width: 100%;
   height: 100%;
@@ -23,4 +29,23 @@
 .monaco-menu .action-label {
   color: #a2bd9b;
   letter-spacing: 0.02em;
-}
\ No newline at end of file
+}
+
+#challege-page-tabs .nav-tabs {
+  margin-left: 2px;
+  display: flex;
+}
+
+#challege-page-tabs .nav-tabs > li {
+  flex: 1;
+  text-align: center;
+}
+
+#challege-page-tabs .nav-tabs > li > a {
+  padding: 5px 10px;
+}
+
+.challege-edittor-wrapper {
+  height: calc(100vh - 112px);
+  overflow: hidden;
+}
diff --git a/client/src/templates/Challenges/components/CompletionModal.js b/client/src/templates/Challenges/components/CompletionModal.js
index 216c09a3a1..b7c7908b7d 100644
--- a/client/src/templates/Challenges/components/CompletionModal.js
+++ b/client/src/templates/Challenges/components/CompletionModal.js
@@ -112,7 +112,7 @@ export class CompletionModal extends Component {
             bsStyle='primary'
             onClick={submitChallenge}
             >
-            Submit and go to next challenge (Ctrl + Enter)
+            Submit and go to next challenge <span className='hidden-xs'>(Ctrl + Enter)</span>
           </Button>
           {showDownloadButton ? (
             <Button
diff --git a/client/src/templates/Challenges/components/HelpModal.js b/client/src/templates/Challenges/components/HelpModal.js
index 8600097c05..3354622d29 100644
--- a/client/src/templates/Challenges/components/HelpModal.js
+++ b/client/src/templates/Challenges/components/HelpModal.js
@@ -7,6 +7,8 @@ import { Button, Modal } from '@freecodecamp/react-bootstrap';
 import ga from '../../../analytics';
 import { createQuestion, closeModal, isHelpModalOpenSelector } from '../redux';
 
+import './help-modal.css';
+
 const mapStateToProps = state => ({ isOpen: isHelpModalOpenSelector(state) });
 const mapDispatchToProps = dispatch =>
   bindActionCreators(
@@ -31,7 +33,7 @@ export class HelpModal extends Component {
       ga.modalview('/help-modal');
     }
     return (
-      <Modal onHide={closeHelpModal} show={isOpen}>
+      <Modal dialogClassName='help-modal' onHide={closeHelpModal} show={isOpen}>
         <Modal.Header
           className='help-modal-header fcc-modal'
           closeButton={true}
diff --git a/client/src/templates/Challenges/components/Preview.js b/client/src/templates/Challenges/components/Preview.js
index dfae74a4a6..2e8593846e 100644
--- a/client/src/templates/Challenges/components/Preview.js
+++ b/client/src/templates/Challenges/components/Preview.js
@@ -1,13 +1,26 @@
 import React, { Component } from 'react';
+import { bindActionCreators } from 'redux';
+import { connect } from 'react-redux';
 import PropTypes from 'prop-types';
 
+import { previewMounted } from '../redux';
+
 import './preview.css';
 
 const mainId = 'fcc-main-frame';
 
+const mapDispatchToProps = dispatch =>
+  bindActionCreators(
+    {
+      previewMounted
+    },
+    dispatch
+  );
+
 const propTypes = {
   className: PropTypes.string,
-  disableIframe: PropTypes.bool
+  disableIframe: PropTypes.bool,
+  previewMounted: PropTypes.func.isRequired
 };
 
 class Preview extends Component {
@@ -19,6 +32,10 @@ class Preview extends Component {
     };
   }
 
+  componentDidMount() {
+    this.props.previewMounted();
+  }
+
   componentDidUpdate(prevProps) {
     if (this.props.disableIframe !== prevProps.disableIframe) {
       // eslint-disable-next-line react/no-did-update-set-state
@@ -39,4 +56,7 @@ class Preview extends Component {
 Preview.displayName = 'Preview';
 Preview.propTypes = propTypes;
 
-export default Preview;
+export default connect(
+  null,
+  mapDispatchToProps
+)(Preview);
diff --git a/client/src/templates/Challenges/components/Side-Panel.js b/client/src/templates/Challenges/components/Side-Panel.js
index eda5547ce7..0cf34614e5 100644
--- a/client/src/templates/Challenges/components/Side-Panel.js
+++ b/client/src/templates/Challenges/components/Side-Panel.js
@@ -34,6 +34,7 @@ const propTypes = {
   initConsole: PropTypes.func.isRequired,
   instructions: PropTypes.string,
   section: PropTypes.string,
+  showToolPanel: PropTypes.bool,
   tests: PropTypes.arrayOf(PropTypes.object),
   title: PropTypes.string,
   videoUrl: PropTypes.string
@@ -89,6 +90,7 @@ export class SidePanel extends Component {
       guideUrl,
       tests,
       section,
+      showToolPanel,
       videoUrl
     } = this.props;
     return (
@@ -99,7 +101,9 @@ export class SidePanel extends Component {
           <ChallengeTitle>{title}</ChallengeTitle>
           <ChallengeDescription description={description} instructions={instructions} section={section} />
         </div>
-        <ToolPanel guideUrl={guideUrl} videoUrl={videoUrl} />
+        { showToolPanel && (
+          <ToolPanel guideUrl={guideUrl} videoUrl={videoUrl} />
+        )}
         <TestSuite tests={tests} />
       </div>
     );
diff --git a/client/src/templates/Challenges/components/Tool-Panel.js b/client/src/templates/Challenges/components/Tool-Panel.js
index 22f235c815..d214389593 100644
--- a/client/src/templates/Challenges/components/Tool-Panel.js
+++ b/client/src/templates/Challenges/components/Tool-Panel.js
@@ -23,6 +23,7 @@ const mapDispatchToProps = dispatch =>
 const propTypes = {
   executeChallenge: PropTypes.func.isRequired,
   guideUrl: PropTypes.string,
+  isMobile: PropTypes.bool,
   openHelpModal: PropTypes.func.isRequired,
   openResetModal: PropTypes.func.isRequired,
   openVideoModal: PropTypes.func.isRequired,
@@ -31,6 +32,7 @@ const propTypes = {
 
 function ToolPanel({
   executeChallenge,
+  isMobile,
   openHelpModal,
   openVideoModal,
   openResetModal,
@@ -39,9 +41,11 @@ function ToolPanel({
 }) {
   return (
     <Fragment>
-      <div className='tool-panel-group'>
+      <div className={`tool-panel-group ${
+          isMobile ? 'tool-panel-group-mobile' : ''
+        }`}>
         <Button block={true} bsStyle='primary' onClick={executeChallenge}>
-          Run the Tests
+          {isMobile ? 'Run' : 'Run the Tests'}
         </Button>
         <Button
           block={true}
@@ -49,7 +53,7 @@ function ToolPanel({
           className='btn-primary-invert'
           onClick={openResetModal}
           >
-          Reset All Code
+          {isMobile ? 'Reset' : 'Reset All Code'}
         </Button>
         {guideUrl ? (
           <Button
@@ -59,7 +63,7 @@ function ToolPanel({
             href={guideUrl}
             target='_blank'
             >
-            Get a hint
+            {isMobile ? 'Hint' : 'Get a hint'}
           </Button>
         ) : null}
         {videoUrl ? (
@@ -69,7 +73,7 @@ function ToolPanel({
             className='btn-primary-invert'
             onClick={openVideoModal}
             >
-            Watch a video
+            {isMobile ? 'Video' : 'Watch a video'}
           </Button>
         ) : null}
         <Button
@@ -78,7 +82,7 @@ function ToolPanel({
           className='btn-primary-invert'
           onClick={openHelpModal}
           >
-          Ask for help
+          {isMobile ? 'Help' : 'Ask for help'}
         </Button>
       </div>
     </Fragment>
diff --git a/client/src/templates/Challenges/components/completion-modal.css b/client/src/templates/Challenges/components/completion-modal.css
index 1e8c67eedd..0970bdc871 100644
--- a/client/src/templates/Challenges/components/completion-modal.css
+++ b/client/src/templates/Challenges/components/completion-modal.css
@@ -9,3 +9,9 @@
   height: 30vh;
   width: 30vh;
 }
+
+@media screen, (max-width: 767px) {
+  .challenge-success-modal .btn-lg {
+    font-size: 16px;
+  }
+}
diff --git a/client/src/templates/Challenges/components/help-modal.css b/client/src/templates/Challenges/components/help-modal.css
new file mode 100644
index 0000000000..ac54f7f115
--- /dev/null
+++ b/client/src/templates/Challenges/components/help-modal.css
@@ -0,0 +1,5 @@
+@media screen, (max-width: 767px) {
+  .help-modal .btn-lg {
+    font-size: 16px;
+  }
+}
diff --git a/client/src/templates/Challenges/components/preview.css b/client/src/templates/Challenges/components/preview.css
index 338dc0f19e..24498dc399 100644
--- a/client/src/templates/Challenges/components/preview.css
+++ b/client/src/templates/Challenges/components/preview.css
@@ -3,6 +3,13 @@
   width: 100%;
   padding: 0;
   margin: 0;
+  border: none;
+}
+
+@media screen, (max-width: 767px) {
+  .challenge-preview, .challenge-preview-frame {
+    height: calc(100vh - 112px);
+  }
 }
 
 .enable-iframe {
diff --git a/client/src/templates/Challenges/components/reset-modal.css b/client/src/templates/Challenges/components/reset-modal.css
index 5e561d1fe7..76a560e495 100644
--- a/client/src/templates/Challenges/components/reset-modal.css
+++ b/client/src/templates/Challenges/components/reset-modal.css
@@ -8,4 +8,10 @@
   color: #fff;
   font-size: 28px;
   text-shadow: none;
-}
\ No newline at end of file
+}
+
+@media screen, (max-width: 767px) {
+  .reset-modal .btn-lg {
+    font-size: 16px;
+  }
+}
diff --git a/client/src/templates/Challenges/components/tool-panel.css b/client/src/templates/Challenges/components/tool-panel.css
index fc70fdc2b3..fe5e09fce9 100644
--- a/client/src/templates/Challenges/components/tool-panel.css
+++ b/client/src/templates/Challenges/components/tool-panel.css
@@ -1,3 +1,17 @@
 .tool-panel-group button, .tool-panel-group a {
   font-size: 1.1rem;
 }
+
+.tool-panel-group-mobile button, .tool-panel-group-mobile a {
+  font-size: 16px;
+}
+
+.tool-panel-group-mobile {
+  display: flex;
+  flex-direction: row-reverse;
+  padding: 0 2px;
+  background: #fff;
+}
+.tool-panel-group-mobile .btn-block + .btn-block {
+  margin: 0 2px 0 0;
+}
diff --git a/client/src/templates/Challenges/redux/execute-challenge-epic.js b/client/src/templates/Challenges/redux/execute-challenge-epic.js
index 57f657da18..dd45bf8c2d 100644
--- a/client/src/templates/Challenges/redux/execute-challenge-epic.js
+++ b/client/src/templates/Challenges/redux/execute-challenge-epic.js
@@ -43,7 +43,12 @@ const executeDebounceTimeout = 750;
 
 function updateMainEpic(action$, state$, { document }) {
   return action$.pipe(
-    ofType(types.updateFile, types.challengeMounted),
+    ofType(
+      types.updateFile,
+      types.previewMounted,
+      types.challengeMounted,
+      types.resetChallenge
+    ),
     filter(() => {
       const { challengeType } = challengeMetaSelector(state$.value);
       return (
diff --git a/client/src/templates/Challenges/redux/index.js b/client/src/templates/Challenges/redux/index.js
index 4dd3f5eece..46abdd15c1 100644
--- a/client/src/templates/Challenges/redux/index.js
+++ b/client/src/templates/Challenges/redux/index.js
@@ -67,6 +67,7 @@ export const types = createTypes(
     'closeModal',
     'openModal',
 
+    'previewMounted',
     'challengeMounted',
     'checkChallenge',
     'executeChallenge',
@@ -74,6 +75,8 @@ export const types = createTypes(
     'submitChallenge',
     'submitComplete',
 
+    'moveToTab',
+
     ...createAsyncTypes('fetchIdToNameMap')
   ],
   ns
@@ -143,6 +146,7 @@ export const noStoredCodeFound = createAction(types.noStoredCodeFound);
 export const closeModal = createAction(types.closeModal);
 export const openModal = createAction(types.openModal);
 
+export const previewMounted = createAction(types.challengeMounted);
 export const challengeMounted = createAction(types.challengeMounted);
 export const checkChallenge = createAction(types.checkChallenge);
 export const executeChallenge = createAction(types.executeChallenge);
@@ -150,6 +154,9 @@ export const resetChallenge = createAction(types.resetChallenge);
 export const submitChallenge = createAction(types.submitChallenge);
 export const submitComplete = createAction(types.submitComplete);
 
+export const moveToTab = createAction(types.moveToTab);
+
+export const currentTabSelector = state => state[ns].currentTab;
 export const challengeFilesSelector = state => state[ns].challengeFiles;
 export const challengeIdToNameMapSelector = state =>
   state[ns].challengeIdToNameMap;
@@ -234,6 +241,7 @@ export const reducer = handleActions(
 
     [types.resetChallenge]: state => ({
       ...state,
+      currentTab: 2,
       challengeFiles: {
         ...Object.keys(state.challengeFiles)
           .map(key => state.challengeFiles[key])
@@ -291,6 +299,14 @@ export const reducer = handleActions(
         ...state.modal,
         [payload]: true
       }
+    }),
+    [types.moveToTab]: (state, { payload }) => ({
+      ...state,
+      currentTab: payload
+    }),
+    [types.executeChallenge]: (state, { payload }) => ({
+      ...state,
+      currentTab: 3
     })
   },
   initialState
diff --git a/client/src/templates/Introduction/Intro.js b/client/src/templates/Introduction/Intro.js
index ed93aef7af..e2b9f1cbeb 100644
--- a/client/src/templates/Introduction/Intro.js
+++ b/client/src/templates/Introduction/Intro.js
@@ -44,31 +44,33 @@ function IntroductionPage({ data: { markdownRemark, allChallengeNode } }) {
       <Helmet>
         <title>{block} | freeCodeCamp</title>
       </Helmet>
-      <FullWidthRow>
-        <div
-          className='intro-layout'
-          dangerouslySetInnerHTML={{ __html: html }}
-        />
-      </FullWidthRow>
-      <FullWidthRow>
-        <Link className='btn btn-lg btn-primary btn-block' to={firstLessonPath}>
-          Go to the first lesson
-        </Link>
-        <ButtonSpacer />
-        <Link to='/learn'>
-          <Button block={true} bsSize='lg' className='btn-primary-invert'>
-            View the curriculum
-          </Button>
-        </Link>
-        <ButtonSpacer />
-        <hr />
-      </FullWidthRow>
-      <FullWidthRow>
-        <h2 className='intro-toc-title'>Upcoming Lessons</h2>
-        <ListGroup className='intro-toc'>
-          {allChallengeNode ? renderMenuItems(allChallengeNode) : null}
-        </ListGroup>
-      </FullWidthRow>
+      <div className='intro-layout-container'>
+        <FullWidthRow>
+          <div
+            className='intro-layout'
+            dangerouslySetInnerHTML={{ __html: html }}
+          />
+        </FullWidthRow>
+        <FullWidthRow>
+          <Link className='btn btn-lg btn-primary btn-block' to={firstLessonPath}>
+            Go to the first lesson
+          </Link>
+          <ButtonSpacer />
+          <Link to='/learn'>
+            <Button block={true} bsSize='lg' className='btn-primary-invert'>
+              View the curriculum
+            </Button>
+          </Link>
+          <ButtonSpacer />
+          <hr />
+        </FullWidthRow>
+        <FullWidthRow>
+          <h2 className='intro-toc-title'>Upcoming Lessons</h2>
+          <ListGroup className='intro-toc'>
+            {allChallengeNode ? renderMenuItems(allChallengeNode) : null}
+          </ListGroup>
+        </FullWidthRow>
+      </div>
     </LearnLayout>
   );
 }
diff --git a/client/src/templates/Introduction/intro.css b/client/src/templates/Introduction/intro.css
index 5fb9d1946d..1e82af8973 100644
--- a/client/src/templates/Introduction/intro.css
+++ b/client/src/templates/Introduction/intro.css
@@ -1,3 +1,9 @@
+@media screen, (max-width: 767px) {
+  .intro-layout-container {
+    padding: 0 10px;
+  }
+}
+
 .intro-layout {
   margin-top: 1.45rem;
 }