:css
  /* Basic reset */
      * {
          margin: 0;
          padding: 0;
      }

      table {
          width: 100%;
          border-collapse: collapse;
      }

      th, td {
          vertical-align: top;
          text-align: left;
      }

      textarea {
          resize: none;
      }

      body {
          font-size: 10pt;
      }

      body, td, input, textarea {
          font-family: helvetica neue, lucida grande, sans-serif;
          line-height: 1.5;
          color: #333;
          text-shadow: 0 1px 0 rgba(255, 255, 255, 0.6);
      }

      html {
          background: #f0f0f5;
      }

      .clearfix::after{
          clear: both;
          content: ".";
          display: block;
          height: 0;
          visibility: hidden;
      }

      /* ---------------------------------------------------------------------
       * Basic layout
       * --------------------------------------------------------------------- */

      /* Small */
      @media screen and (max-width: 1100px) {
          html {
              overflow-y: scroll;
          }

          body {
              margin: 0 20px;
          }

          header.exception {
              margin: 0 -20px;
          }

          nav.sidebar {
              padding: 0;
              margin: 20px 0;
          }

          ul.frames {
              max-height: 200px;
              overflow: auto;
          }
      }

      /* Wide */
      @media screen and (min-width: 1100px) {
          header.exception {
             position: fixed;
             top: 0;
             left: 0;
             right: 0;
          }

          nav.sidebar,
          .frame_info {
              position: fixed;
              top: 95px;
              bottom: 0;

              box-sizing: border-box;

              overflow-y: auto;
              overflow-x: hidden;
          }

          nav.sidebar {
              width: 40%;
              left: 20px;
              top: 115px;
              bottom: 20px;
          }

          .frame_info {
              right: 0;
              left: 40%;

              padding: 20px;
              padding-left: 10px;
              margin-left: 30px;
          }
      }

      nav.sidebar {
          background: #d3d3da;
          border-top: solid 3px #a33;
          border-bottom: solid 3px #a33;
          border-radius: 4px;
          box-shadow: 0 0 6px rgba(0, 0, 0, 0.2), inset 0 0 0 1px rgba(0, 0, 0, 0.1);
      }

      /* ---------------------------------------------------------------------
       * Header
       * --------------------------------------------------------------------- */

      header.exception {
          padding: 18px 20px;

          height: 59px;
          min-height: 59px;

          overflow: hidden;

          background-color: #20202a;
          color: #aaa;
          text-shadow: 0 1px 0 rgba(0, 0, 0, 0.3);
          font-weight: 200;
          box-shadow: inset 0 -5px 3px -3px rgba(0, 0, 0, 0.05), inset 0 -1px 0 rgba(0, 0, 0, 0.05);

          -webkit-text-smoothing: antialiased;
      }

      /* Heading */
      header.exception h2 {
          font-weight: 200;
          font-size: 11pt;
      }

      header.exception h2,
      header.exception p {
          line-height: 1.4em;
          overflow: hidden;
          white-space: pre;
          text-overflow: ellipsis;
      }

      header.exception h2 strong {
          font-weight: 700;
          color: #d55;
      }

      header.exception p {
          font-weight: 200;
          font-size: 20pt;
          color: white;
      }

      header.exception:hover {
          height: auto;
          z-index: 2;
      }

      header.exception:hover h2,
      header.exception:hover p {
          padding-right: 20px;
          overflow-y: auto;
          word-wrap: break-word;
          white-space: pre-wrap;
          height: auto;
          max-height: 7.5em;
      }

      @media screen and (max-width: 1100px) {
          header.exception {
              height: auto;
          }

          header.exception h2,
          header.exception p {
              padding-right: 20px;
              overflow-y: auto;
              word-wrap: break-word;
              height: auto;
              max-height: 7em;
          }
      }

  <haml_silent>













  </haml_silent>
      /* ---------------------------------------------------------------------
       * Navigation
       * --------------------------------------------------------------------- */

      nav.tabs {
          border-bottom: solid 1px #ddd;

          background-color: #eee;
          text-align: center;

          padding: 6px;

          box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.1);
      }

      nav.tabs a {
          display: inline-block;

          height: 22px;
          line-height: 22px;
          padding: 0 10px;

          text-decoration: none;
          font-size: 8pt;
          font-weight: bold;

          color: #999;
          text-shadow: 0 1px 0 rgba(255, 255, 255, 0.6);
      }

      nav.tabs a.selected {
          color: white;
          background: rgba(0, 0, 0, 0.5);
          border-radius: 16px;
          box-shadow: 1px 1px 0 rgba(255, 255, 255, 0.1);
          text-shadow: 0 0 4px rgba(0, 0, 0, 0.4), 0 1px 0 rgba(0, 0, 0, 0.4);
      }

      nav.tabs a.disabled {
          text-decoration: line-through;
          text-shadow: none;
          cursor: default;
      }

      /* ---------------------------------------------------------------------
       * Sidebar
       * --------------------------------------------------------------------- */

      ul.frames {
          box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
      }

      /* Each item */
      ul.frames li {
          background-color: #f8f8f8;
          background: -webkit-linear-gradient(top, #f8f8f8 80%, #f0f0f0);
          background: -moz-linear-gradient(top, #f8f8f8 80%, #f0f0f0);
          background: linear-gradient(top, #f8f8f8 80%, #f0f0f0);
          box-shadow: inset 0 -1px 0 #e2e2e2;
          padding: 7px 20px;

          cursor: pointer;
          overflow: hidden;
      }

      ul.frames .name,
      ul.frames .location {
          overflow: hidden;
          height: 1.5em;

          white-space: nowrap;
          word-wrap: none;
          text-overflow: ellipsis;
      }

      ul.frames .method {
          color: #966;
      }

      ul.frames .location {
          font-size: 0.85em;
          font-weight: 400;
          color: #999;
      }

      ul.frames .line {
          font-weight: bold;
      }

      /* Selected frame */
      ul.frames li.selected {
          background: #38a;
          box-shadow: inset 0 1px 0 rgba(0, 0, 0, 0.1), inset 0 2px 0 rgba(255, 255, 255, 0.01), inset 0 -1px 0 rgba(0, 0, 0, 0.1);
      }

      ul.frames li.selected .name,
      ul.frames li.selected .method,
      ul.frames li.selected .location {
          color: white;
          text-shadow: 0 1px 0 rgba(0, 0, 0, 0.2);
      }

      ul.frames li.selected .location {
          opacity: 0.6;
      }

      /* Iconography */
      ul.frames li {
          padding-left: 60px;
          position: relative;
      }

      ul.frames li .icon {
          display: block;
          width: 20px;
          height: 20px;
          line-height: 20px;
          border-radius: 15px;

          text-align: center;

          background: white;
          border: solid 2px #ccc;

          font-size: 9pt;
          font-weight: 200;
          font-style: normal;

          position: absolute;
          top: 14px;
          left: 20px;
      }

      ul.frames .icon.application {
          background: #808090;
          border-color: #555;
      }

      ul.frames .icon.application:before {
          content: 'A';
          color: white;
          text-shadow: 0 0 3px rgba(0, 0, 0, 0.2);
      }

      /* Responsiveness -- flow to single-line mode */
      @media screen and (max-width: 1100px) {
          ul.frames li {
              padding-top: 6px;
              padding-bottom: 6px;
              padding-left: 36px;
              line-height: 1.3;
          }

          ul.frames li .icon {
              width: 11px;
              height: 11px;
              line-height: 11px;

              top: 7px;
              left: 10px;
              font-size: 5pt;
          }

          ul.frames .name,
          ul.frames .location {
              display: inline-block;
              line-height: 1.3;
              height: 1.3em;
          }

          ul.frames .name {
              margin-right: 10px;
          }
      }

      /* ---------------------------------------------------------------------
       * Monospace
       * --------------------------------------------------------------------- */

      pre, code, .be-repl input, .be-repl .command-line span, textarea, .code_linenums {
          font-family: menlo, lucida console, monospace;
          font-size: 8pt;
      }

      /* ---------------------------------------------------------------------
       * Display area
       * --------------------------------------------------------------------- */

      .trace_info {
          background: #fff;
          padding: 6px;
          border-radius: 3px;
          margin-bottom: 2px;
          box-shadow: 0 0 10px rgba(0, 0, 0, 0.03), 1px 1px 0 rgba(0, 0, 0, 0.05), -1px 1px 0 rgba(0, 0, 0, 0.05), 0 0 0 4px rgba(0, 0, 0, 0.04);
      }

      .code_block{
          background: #f1f1f1;
          border-left: 1px solid #ccc;
      }

      /* Titlebar */
      .trace_info .title {
          background: #f1f1f1;

          box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.3);
          overflow: hidden;
          padding: 6px 10px;

          border: solid 1px #ccc;
          border-bottom: 0;

          border-top-left-radius: 2px;
          border-top-right-radius: 2px;
      }

      .trace_info .title .name,
      .trace_info .title .location {
          font-size: 9pt;
          line-height: 26px;
          height: 26px;
          overflow: hidden;
      }

      .trace_info .title .location {
          float: left;
          font-weight: bold;
          font-size: 10pt;
      }

      .trace_info .title .location a {
          color:inherit;
          text-decoration:none;
          border-bottom:1px solid #aaaaaa;
      }

      .trace_info .title .location a:hover {
          border-color:#666666;
      }

      .trace_info .title .name {
          float: right;
          font-weight: 200;
      }

      .code, .be-console, .unavailable {
          background: #fff;
          padding: 5px;

          box-shadow: inset 3px 3px 3px rgba(0, 0, 0, 0.1), inset 0 0 0 1px rgba(0, 0, 0, 0.1);
      }

      .code_linenums{
          background:#f1f1f1;
          padding-top:10px;
          padding-bottom:9px;
          float:left;
      }

      .code_linenums span{
          display:block;
          padding:0 12px;
      }

      .code {
          margin-bottom: -1px;
          border-top-left-radius:2px;
          padding: 10px 0;
          overflow: auto;
      }

      .code pre{
          padding-left:12px;
          min-height:16px;
      }

      /* Source unavailable */
      p.unavailable {
          padding: 20px 0 40px 0;
          text-align: center;
          color: #b99;
          font-weight: bold;
      }

      p.unavailable:before {
          content: '\00d7';
          display: block;

          color: #daa;

          text-align: center;
          font-size: 40pt;
          font-weight: normal;
          margin-bottom: -10px;
      }

      @-webkit-keyframes highlight {
          0%   { background: rgba(220, 30, 30, 0.3); }
          100% { background: rgba(220, 30, 30, 0.1); }
      }
      @-moz-keyframes highlight {
          0%   { background: rgba(220, 30, 30, 0.3); }
          100% { background: rgba(220, 30, 30, 0.1); }
      }
      @keyframes highlight {
          0%   { background: rgba(220, 30, 30, 0.3); }
          100% { background: rgba(220, 30, 30, 0.1); }
      }

      .code .highlight, .code_linenums .highlight {
          background: rgba(220, 30, 30, 0.1);
          -webkit-animation: highlight 400ms linear 1;
          -moz-animation: highlight 400ms linear 1;
          animation: highlight 400ms linear 1;
      }

      /* REPL shell */
      .be-console {
          padding: 0 1px 10px 1px;
          border-bottom-left-radius: 2px;
          border-bottom-right-radius: 2px;
      }

      .be-console pre {
          padding: 10px 10px 0 10px;
          max-height: 400px;
          overflow-x: none;
          overflow-y: auto;
          margin-bottom: -3px;
          word-wrap: break-word;
          white-space: pre-wrap;
      }

      /* .command-line > span + input */
      .be-console .command-line {
          display: table;
          width: 100%;
      }

      .be-console .command-line span,
      .be-console .command-line input {
          display: table-cell;
      }

      .be-console .command-line span {
          width: 1%;
          padding-right: 5px;
          padding-left: 10px;
          white-space: pre;
      }

      .be-console .command-line input {
          width: 99%;
      }

      /* Input box */
      .be-console input,
      .be-console input:focus {
          outline: 0;
          border: 0;
          padding: 0;
          background: transparent;
          margin: 0;
      }

      /* Hint text */
      .hint {
          margin: 15px 0 20px 0;
          font-size: 8pt;
          color: #8080a0;
          padding-left: 20px;
      }

      .hint:before {
          content: '\25b2';
          margin-right: 5px;
          opacity: 0.5;
      }

      /* ---------------------------------------------------------------------
       * Variable infos
       * --------------------------------------------------------------------- */

      .sub {
          padding: 10px 0;
          margin: 10px 0;
      }

      .sub:before {
          content: '';
          display: block;
          width: 100%;
          height: 4px;

          border-radius: 2px;
          background: rgba(0, 150, 200, 0.05);
          box-shadow: 1px 1px 0 rgba(255, 255, 255, 0.7), inset 0 0 0 1px rgba(0, 0, 0, 0.04), inset 2px 2px 2px rgba(0, 0, 0, 0.07);
      }

      .sub h3 {
          color: #39a;
          font-size: 1.1em;
          margin: 10px 0;
          text-shadow: 0 1px 0 rgba(255, 255, 255, 0.6);

          -webkit-font-smoothing: antialiased;
      }

      .sub .inset {
          overflow-y: auto;
      }

      .sub table {
          table-layout: fixed;
      }

      .sub table td {
          border-top: dotted 1px #ddd;
          padding: 7px 1px;
      }

      .sub table td.name {
          width: 150px;

          font-weight: bold;
          font-size: 0.8em;
          padding-right: 20px;

          word-wrap: break-word;
      }

      .sub table td pre {
          max-height: 15em;
          overflow-y: auto;
      }

      .sub table td pre {
          width: 100%;

          word-wrap: break-word;
          white-space: normal;
      }

      /* "(object doesn't support inspect)" */
      .sub .unsupported {
        font-family: sans-serif;
        color: #777;
      }

      /* ---------------------------------------------------------------------
       * Scrollbar
       * --------------------------------------------------------------------- */

      nav.sidebar::-webkit-scrollbar,
      .inset pre::-webkit-scrollbar,
      .be-console pre::-webkit-scrollbar,
      .code::-webkit-scrollbar {
          width: 10px;
          height: 10px;
      }

      .inset pre::-webkit-scrollbar-thumb,
      .be-console pre::-webkit-scrollbar-thumb,
      .code::-webkit-scrollbar-thumb {
          background: #ccc;
          border-radius: 5px;
      }

      nav.sidebar::-webkit-scrollbar-thumb {
          background: rgba(0, 0, 0, 0.0);
          border-radius: 5px;
      }

      nav.sidebar:hover::-webkit-scrollbar-thumb {
          background-color: #999;
          background: -webkit-linear-gradient(left, #aaa, #999);
      }

      .be-console pre:hover::-webkit-scrollbar-thumb,
      .inset pre:hover::-webkit-scrollbar-thumb,
      .code:hover::-webkit-scrollbar-thumb {
          background: #888;
      }
:javascript
  (function() {
      var elements = ["section", "nav", "header", "footer", "audio"];
      for (var i = 0; i < elements.length; i++) {
          document.createElement(elements[i]);
      }
  })();
:javascript
  if (window.Turbolinks) {
      for(var i=0; i < document.styleSheets.length; i++) {
          if(document.styleSheets[i].href)
              document.styleSheets[i].disabled = true;
      }
      if (window.Turbolinks.controller) {
          // Turbolinks > 5 (see https://github.com/turbolinks/turbolinks/issues/6)
          document.addEventListener("turbolinks:load", function restoreCSS(e) {
              for(var i=0; i < document.styleSheets.length; i++) {
                  document.styleSheets[i].disabled = false;
              }
              document.removeEventListener("turbolinks:load", restoreCSS, false);
          });
      } else {
          document.addEventListener("page:restore", function restoreCSS(e) {
              for(var i=0; i < document.styleSheets.length; i++) {
                  document.styleSheets[i].disabled = false;
              }
              document.removeEventListener("page:restore", restoreCSS, false);
          });
      }
  }
.top
  %header.exception
    %h2
      %strong= exception_type
      %span
        at #{request_path}
    %p= exception_message
%section.backtrace
  %nav.sidebar
    %nav.tabs
      %a#application_frames{:href => "#"} Application Frames
      %a#all_frames{:href => "#"} All Frames
    %ul.frames
      - backtrace_frames.each_with_index do |frame, index|
        %li{:class => "#{frame.context}", "data-context" => "#{frame.context}", "data-index" => index}
          %span.stroke
          %i{:class => "icon #{frame.context}"}
          .info
            .name
              %strong= frame.class_name
              %span.method= frame.method_name
            .location
              %span.filename>= frame.pretty_path
              , line
              %span.line= frame.line
  - backtrace_frames.each_with_index do |frame, index|
    .frame_info{:id => "frame_info_#{index}", :style => "display:none;"}
:javascript
  (function() {

    var OID = "#{id}";

    var previousFrame = null;
    var previousFrameInfo = null;
    var allFrames = document.querySelectorAll("ul.frames li");
    var allFrameInfos = document.querySelectorAll(".frame_info");

    function apiCall(method, opts, cb) {
        var req = new XMLHttpRequest();
        req.open("POST", "//" + window.location.host + "/__better_errors/" + OID + "/" + method, true);
      req.setRequestHeader("Content-Type", "application/json");
        req.send(JSON.stringify(opts));
        req.onreadystatechange = function() {
            if(req.readyState == 4) {
                var res = JSON.parse(req.responseText);
                cb(res);
            }
        };
    }

    function escapeHTML(html) {
        return html.replace(/&/, "&amp;").replace(/</g, "&lt;");
    }

    function REPL(index) {
        this.index = index;

        var previousCommands = JSON.parse(localStorage.getItem("better_errors_previous_commands"));
        if(previousCommands === null) {
          localStorage.setItem("better_errors_previous_commands", JSON.stringify([]));
          previousCommands = [];
        }

        this.previousCommandOffset = previousCommands.length;
    }

    REPL.all = [];

    REPL.prototype.install = function(containerElement) {
        this.container = containerElement;

        this.promptElement  = this.container.querySelector(".command-line .prompt");
        this.inputElement   = this.container.querySelector("input");
        this.outputElement  = this.container.querySelector("pre");

        var self = this;
        this.inputElement.onkeydown = function(ev) {
            self.onKeyDown(ev);
        };

        this.setPrompt(">>");

        REPL.all[this.index] = this;
    }

    REPL.prototype.focus = function() {
        this.inputElement.focus();
    };

    REPL.prototype.setPrompt = function(prompt) {
        this._prompt = prompt;
        this.promptElement.innerHTML = escapeHTML(prompt);
    };

    REPL.prototype.getInput = function() {
        return this.inputElement.value;
    };

    REPL.prototype.setInput = function(text) {
        this.inputElement.value = text;

        if(this.inputElement.setSelectionRange) {
            // set cursor to end of input
            this.inputElement.setSelectionRange(text.length, text.length);
        }
    };

    REPL.prototype.writeRawOutput = function(output) {
        this.outputElement.innerHTML += output;
        this.outputElement.scrollTop = this.outputElement.scrollHeight;
    };

    REPL.prototype.writeOutput = function(output) {
        this.writeRawOutput(escapeHTML(output));
    };

    REPL.prototype.sendInput = function(line) {
        var self = this;
        apiCall("eval", { "index": this.index, source: line }, function(response) {
            if(response.error) {
                self.writeOutput(response.error + "\n");
            }
            self.writeOutput(self._prompt + " ");
            self.writeRawOutput(response.highlighted_input + "\n");
            self.writeOutput(response.result);
            self.setPrompt(response.prompt);
            self.setInput(response.prefilled_input);
        });
    };

    REPL.prototype.onEnterKey = function() {
        var text = this.getInput();
        if(text != "" && text !== undefined) {
            var previousCommands = JSON.parse(localStorage.getItem("better_errors_previous_commands"));
            this.previousCommandOffset = previousCommands.push(text);
            if(previousCommands.length > 100) {
              previousCommands.splice(0, 1);
              this.previousCommandOffset -= 1;
            }
            localStorage.setItem("better_errors_previous_commands", JSON.stringify(previousCommands));
        }
        this.setInput("");
        this.sendInput(text);
    };

    REPL.prototype.onNavigateHistory = function(direction) {
        this.previousCommandOffset += direction;
        var previousCommands = JSON.parse(localStorage.getItem("better_errors_previous_commands"));

        if(this.previousCommandOffset < 0) {
            this.previousCommandOffset = -1;
            this.setInput("");
            return;
        }

        if(this.previousCommandOffset >= previousCommands.length) {
            this.previousCommandOffset = previousCommands.length;
            this.setInput("");
            return;
        }

        this.setInput(previousCommands[this.previousCommandOffset]);
    };

    REPL.prototype.onKeyDown = function(ev) {
        if(ev.keyCode == 13) {
            this.onEnterKey();
        } else if(ev.keyCode == 38 || (ev.ctrlKey && ev.keyCode == 80)) {
            // the user pressed the up arrow or Ctrl-P
            this.onNavigateHistory(-1);
            ev.preventDefault();
            return false;
        } else if(ev.keyCode == 40 || (ev.ctrlKey && ev.keyCode == 78)) {
            // the user pressed the down arrow or Ctrl-N
            this.onNavigateHistory(1);
            ev.preventDefault();
            return false;
        }
    };

    function switchTo(el) {
        if(previousFrameInfo) previousFrameInfo.style.display = "none";
        previousFrameInfo = el;

        el.style.display = "block";

        var replInput = el.querySelector('.be-console input');
        if (replInput) replInput.focus();
    }

    function selectFrameInfo(index) {
        var el = allFrameInfos[index];
        if(el) {
            if (el.loaded) {
                return switchTo(el);
            }

            apiCall("variables", { "index": index }, function(response) {
                el.loaded = true;
                if(response.error) {
                    el.innerHTML = "<h2 class='error'>" + escapeHTML(response.error) + "</h2>";
                    if(response.explanation) {
                      el.innerHTML += "<p class='explanation'>" + escapeHTML(response.explanation) + "</p>";
                    }
                    el.innerHTML += "<p><a target='_new' href='https://github.com/BetterErrors/better_errors'>More about Better Errors</a></p>";
                } else {
                    el.innerHTML = response.html;

                    var repl = el.querySelector(".be-repl .be-console");
                    if(repl) {
                        new REPL(index).install(repl);
                    }
                }
                switchTo(el);
            });
        }
    }

    for(var i = 0; i < allFrames.length; i++) {
        (function(i, el) {
            var el = allFrames[i];
            el.onclick = function() {
                if(previousFrame) {
                    previousFrame.className = "";
                }
                el.className = "selected";
                previousFrame = el;

                selectFrameInfo(el.attributes["data-index"].value);
            };
        })(i);
    }

    // Click the first application frame
    (
      document.querySelector(".frames li.application") ||
      document.querySelector(".frames li")
    ).onclick();

    // This is the second query performed for frames; maybe the 'allFrames' list
    // currently used and this list can be better used to avoid the repetition:
    var applicationFramesCount = document.querySelectorAll(
        "ul.frames li[data-context=application]"
    ).length;

    var applicationFramesButtonIsInstalled = false;
    var applicationFramesButton = document.getElementById("application_frames");
    var allFramesButton = document.getElementById("all_frames");

    // The application frames button only needs to be bound if
    // there are actually any application frames to look at.
    var installApplicationFramesButton = function() {
        applicationFramesButton.onclick = function() {
            allFramesButton.className = "";
            applicationFramesButton.className = "selected";
            for(var i = 0; i < allFrames.length; i++) {
                if(allFrames[i].attributes["data-context"].value == "application") {
                    allFrames[i].style.display = "block";
                } else {
                    allFrames[i].style.display = "none";
                }
            }
            return false;
        };

        applicationFramesButtonIsInstalled = true;
    }

    allFramesButton.onclick = function() {
        if(applicationFramesButtonIsInstalled) {
            applicationFramesButton.className = "";
        }

        allFramesButton.className = "selected";
        for(var i = 0; i < allFrames.length; i++) {
            allFrames[i].style.display = "block";
        }
        return false;
    };

    // If there are no application frames, select the 'All Frames'
    // tab by default.
    if(applicationFramesCount > 0) {
        installApplicationFramesButton();
        applicationFramesButton.onclick();
    } else {
        applicationFramesButton.className = "disabled";
        applicationFramesButton.title = "No application frames available";
        allFramesButton.onclick();
    }
  })();