e-hentai fullscreen script by Patchwerk

// ==UserScript==
// @name         E-hentai Fullscreen Viewer
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Fullscreen pictures on g.e-hentai.org. Use left and right arrows to navigate.
// @author       patchwerk
// @match        https://e-hentai.org/s/*
// @grant        none
// ==/UserScript==
(function() {
    'use strict';

    var link = document.querySelectorAll("#i3 > a > img");
    var body = document.querySelectorAll("body");
    var sni = document.querySelectorAll(".sni");
    var sn = document.querySelectorAll(".sn a")[1].getAttribute("href");
    var ifd = document.querySelectorAll(".if");
    var tod = document.querySelectorAll(".tod");
    var picto = document.querySelectorAll(".sn");
    var sb = document.querySelectorAll(".sb");
    var ip = document.querySelectorAll(".ip");
    body = body[0];
    sni = sni[0];
    link = link[0];
    var oldHeight = link.offsetHeight;
    var href = document.querySelectorAll(".sni > #i3 > a");
    fullscreen();

    function fullscreen() {
        if (ifd[0] != null) {
            ifd[0].style.display = "none";
        }
        if (tod[0] != null) {
            tod[0].style.display = "none";
        }
        picto[0].style.display = "none";
        picto[1].style.display = "none";
        sb[0].style.display = "none";
        ip[0].style.display = "none";
        body.style.backgroundColor = "#E3E0D1";
        body.style.color = "#E3E0D1";
        sni.style.backgroundColor = "#E3E0D1";
        sni.style.border = "1px solid #E3E0D1";
        link.style.position = "fixed";
        link.style.top = "0";
        link.style.bottom = "0";
        link.style.left = "0";
        link.style.right = "0";
        link.style.width = "";
        link.style.height = "100%";
        link.style.margin = "auto";
        link.style.overflow = "auto";
        link.style.zoom = "10";
        link.style.zIndex = "100";
    }
    document.onkeydown = checkKey;

    function checkKey(e) {
            console.log('ok');

        e = e || window.event;

        if (e.keyCode == '37') {
            window.location.href = sn;
        } else if (e.keyCode == '39') {
            window.location.href = href[0].getAttribute("href");
        } else if (e.keyCode == '27') {
            if (ifd[0] != null) {
                ifd[0].style.display = "block";
            }
            if (tod[0] != null) {
                tod[0].style.display = "block";
            }
            picto[0].style.display = "block";
            picto[1].style.display = "block";
            sb[0].style.display = "block";
            ip[0].style.display = "block";
            body.style.backgroundColor = "#E3E0D1";
            body.style.color = "#5C0D11";
            sni.style.backgroundColor = "#EDEBDF";
            sni.style.border = "1px solid #5C0D12";
            link.style.position = "";
            link.style.top = "";
            link.style.bottom = "";
            link.style.left = "";
            link.style.right = "";
            link.style.width = "";
            link.style.height = oldHeight;
            link.style.margin = "";
            link.style.overflow = "";
            link.style.zoom = "";
            link.style.zIndex = "";
        } else if (e.keyCode == '32') {
            fullscreen();
        }

    }

})();