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Learn the basic events and their features of work.","exercise_id":2264},{"ordered_units":[{"id":7717,"name":"theory","url":"/courses/js-dom/lessons/events-in-action/theory_unit"},{"id":7732,"name":"exercise","url":"/courses/js-dom/lessons/events-in-action/exercise_unit"}],"id":3438,"slug":"events-in-action","state":"approved","name":"Events in practice","course_order":463,"goal":"Learn how to create interactive components","exercise_id":2265},{"ordered_units":[{"id":7718,"name":"theory","url":"/courses/js-dom/lessons/forms/theory_unit"},{"id":8030,"name":"quiz","url":"/courses/js-dom/lessons/forms/quiz_unit"},{"id":7733,"name":"exercise","url":"/courses/js-dom/lessons/forms/exercise_unit"}],"id":3439,"slug":"forms","state":"approved","name":"Forms","course_order":465,"goal":"Learn how to handle forms","exercise_id":2266},{"ordered_units":[{"id":7719,"name":"theory","url":"/courses/js-dom/lessons/event-stages/theory_unit"},{"id":8031,"name":"quiz","url":"/courses/js-dom/lessons/event-stages/quiz_unit"},{"id":7734,"name":"exercise","url":"/courses/js-dom/lessons/event-stages/exercise_unit"}],"id":3440,"slug":"event-stages","state":"approved","name":"Capturing and bubbling","course_order":470,"goal":"Understand the stages of events. Learn how to capture an event and stop it from propagating.","exercise_id":2267},{"ordered_units":[{"id":7720,"name":"theory","url":"/courses/js-dom/lessons/document-events/theory_unit"},{"id":8032,"name":"quiz","url":"/courses/js-dom/lessons/document-events/quiz_unit"}],"id":3441,"slug":"document-events","state":"approved","name":"Document Events","course_order":500,"goal":"Learn events that occur when loading and unloading a document.","exercise_id":null},{"ordered_units":[{"id":7721,"name":"theory","url":"/courses/js-dom/lessons/ajax/theory_unit"},{"id":8033,"name":"quiz","url":"/courses/js-dom/lessons/ajax/quiz_unit"},{"id":7735,"name":"exercise","url":"/courses/js-dom/lessons/ajax/exercise_unit"}],"id":3442,"slug":"ajax","state":"approved","name":"AJAX","course_order":650,"goal":"Learn how to execute AJAX requests using the modern browser API - fetch","exercise_id":2268},{"ordered_units":[{"id":7722,"name":"theory","url":"/courses/js-dom/lessons/jquery/theory_unit"},{"id":8034,"name":"quiz","url":"/courses/js-dom/lessons/jquery/quiz_unit"},{"id":7736,"name":"exercise","url":"/courses/js-dom/lessons/jquery/exercise_unit"}],"id":3443,"slug":"jquery","state":"approved","name":"JQuery","course_order":700,"goal":"Learn to use the jQuery library. Find out why it is required in every job, but companies discontinue to use it.","exercise_id":2269}],"challenges":[{"exercise":{"id":2253,"slug":"js_dom_gem_puzzle_exercise","name":"Пятнашки","state":"active","kind":"challenge","language":"javascript","locale":"en","has_web_view":true,"has_test_view":false,"reviewable":true,"readme":"15 puzzle or gem puzzle is a popular game invented in 1878 by Noah Chapman. It is a set of identical numbered square tiles, enclosed in a square box. The side length of the box is four times the side length of the tiles for a set of 15 elements, while one square field remains empty. The game goal is to arrange tiles by numbers by moving them around the box, preferably by making as few movements as possible.\n\n## application.js\n\nImplement the game according to the following requirements:\n\n* The frame size should be 4x4\n* The lower right square is always empty in the initial game state\n* Elements are arranged randomly according to the following algorithm: first they are shuffled using `randomize(values)`, and then they fill the table\n* The values should be ordered in the table **from top to bottom**, that is, in this way:\n\n ```text\n | 1 | 5 | 9 | 13 |\n |----|----|----|----|\n | 2 | 6 | 10 | 14 |\n |----|----|----|----|\n | 3 | 7 | 11 | 15 |\n |----|----|----|----|\n | 4 | 8 | 12 | |\n ```\n\nThe **tiles** are moved using the arrows: when you press <kbd>→</kbd>, the left tile will move to the right to an empty area.\n\nSince the tests are tied to the layout implementation (Bootstrap) we have a special requirement for it. Here's what the initial state looks like:\n\n```html\n<div class=\"gem-puzzle\">\n <table class=\"table-bordered\">\n <tbody>\n <tr>\n <td class=\"p-3\">10</td>\n <td class=\"p-3\">11</td>\n <td class=\"p-3\">6</td>\n <td class=\"p-3\">4</td>\n </tr>\n <tr>\n <td class=\"p-3\">14</td>\n <td class=\"p-3\">2</td>\n <td class=\"p-3\">12</td>\n <td class=\"p-3\">1</td>\n </tr>\n <tr>\n <td class=\"p-3\">3</td>\n <td class=\"p-3\">13</td>\n <td class=\"p-3\">9</td>\n <td class=\"p-3\">8</td>\n </tr>\n <tr>\n <td class=\"p-3\">5</td>\n <td class=\"p-3\">7</td>\n <td class=\"p-3\">15</td>\n <td class=\"p-3 table-active\"></td>\n </tr>\n </tbody>\n </table>\n</div>\n```\n\n* The table class is constant\n* Each cell has a *p-3* class\n* An empty cell contains no text\n* The *table-active* class is added to an empty cell\n\n\n\n## Tips\n\n* Key press event generates a code indicating which key has been pressed\n* You can check the codes for the arrows in the tests\n* To get a pressed key from an event, use the [key](https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key) property from the event object\n* Use the [keyup](https://developer.mozilla.org/en-US/docs/Web/API/Element/keyup_event) event\n","prepared_readme":"15 puzzle or gem puzzle is a popular game invented in 1878 by Noah Chapman. It is a set of identical numbered square tiles, enclosed in a square box. The side length of the box is four times the side length of the tiles for a set of 15 elements, while one square field remains empty. The game goal is to arrange tiles by numbers by moving them around the box, preferably by making as few movements as possible.\n\n## application.js\n\nImplement the game according to the following requirements:\n\n* The frame size should be 4x4\n* The lower right square is always empty in the initial game state\n* Elements are arranged randomly according to the following algorithm: first they are shuffled using `randomize(values)`, and then they fill the table\n* The values should be ordered in the table **from top to bottom**, that is, in this way:\n\n ```text\n | 1 | 5 | 9 | 13 |\n |----|----|----|----|\n | 2 | 6 | 10 | 14 |\n |----|----|----|----|\n | 3 | 7 | 11 | 15 |\n |----|----|----|----|\n | 4 | 8 | 12 | |\n ```\n\nThe **tiles** are moved using the arrows: when you press <kbd>→</kbd>, the left tile will move to the right to an empty area.\n\nSince the tests are tied to the layout implementation (Bootstrap) we have a special requirement for it. Here's what the initial state looks like:\n\n```html\n<div class=\"gem-puzzle\">\n <table class=\"table-bordered\">\n <tbody>\n <tr>\n <td class=\"p-3\">10</td>\n <td class=\"p-3\">11</td>\n <td class=\"p-3\">6</td>\n <td class=\"p-3\">4</td>\n </tr>\n <tr>\n <td class=\"p-3\">14</td>\n <td class=\"p-3\">2</td>\n <td class=\"p-3\">12</td>\n <td class=\"p-3\">1</td>\n </tr>\n <tr>\n <td class=\"p-3\">3</td>\n <td class=\"p-3\">13</td>\n <td class=\"p-3\">9</td>\n <td class=\"p-3\">8</td>\n </tr>\n <tr>\n <td class=\"p-3\">5</td>\n <td class=\"p-3\">7</td>\n <td class=\"p-3\">15</td>\n <td class=\"p-3 table-active\"></td>\n </tr>\n </tbody>\n </table>\n</div>\n```\n\n* The table class is constant\n* Each cell has a *p-3* class\n* An empty cell contains no text\n* The *table-active* class is added to an empty cell\n\n\n\n## Tips\n\n* Key press event generates a code indicating which key has been pressed\n* You can check the codes for the arrows in the tests\n* To get a pressed key from an event, use the [key](https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key) property from the event object\n* Use the [keyup](https://developer.mozilla.org/en-US/docs/Web/API/Element/keyup_event) event\n","has_solution":true,"entity_name":"Пятнашки"},"course":{"start_lesson":{"exercise":null,"units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"links":[],"ordered_units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"id":3426,"slug":"intro","state":"approved","name":"Introduction","course_order":100,"goal":"Learn about the course and its objectives","self_study":null,"theory_video_provider":null,"theory_video_uid":null,"theory":"Today’s websites are highly interactive. Pages rarely reload, so we can change their content instantly.\n\nSoftware solutions have become so complex. Now we can open a browser and use programs like Photoshop, packages similar to Microsoft Office, or full-blown development environments such as our Hexlet editor.\n\nBrowser games are an enormous industry too. These games are no worse than regular desktop ones, thanks to hardware support.\n\nNone of this would be possible without JavaScript.\n\nJavaScript, which was originally used to add snowflakes to a web page, has become a powerful tool for professionals. To date, JavaScript is the only language that browsers can execute.\n\nBut a language is not enough to bring a page to life. The browser should provide a way to manage both the pages and the browser itself. Most of these features are standardized and described in the HTML5 specifications. Some of them are:\n\n* Manipulating page content\n* Managing appearance\n* Responding to user actions\n* Working with cookies\n* Controlling the browser's address bar, navigation, history\n* Interacting with the server\n* Video playback\n* Input/Output\n* Interacting with file systems and networks\n* 2D/3D drawing\n\nFrom the language’s point of view, most of these features look like global objects that you can interact with within the program. The most basic and important object in this system is the **DOM tree**.\n\nIn this course, we’ll learn how to implement JavaScript on a website, go through the fundamental ways to modify a page, get acquainted with polyfills, make our first Ajax request, and discover the world of events.\n\nAfter this course, you’ll try your hand at creating simple front-end games.\n\n## How to prepare for the course\n\nThis course is about animating pages in browsers using JavaScript. This course assumes that you’ve already studied JavaScript, either in Hexlet or on any other platform.\n"},"id":331,"slug":"js-dom","challenges_count":4,"name":"JS: DOM API","allow_indexing":true,"state":"approved","course_state":"finished","pricing_type":"paid","description":"The browser is a special environment in which JavaScript gets the opportunity to interact with loaded website pages. To do this, the browser provides special objects with a large number of methods. With their help, we can perform any HTML transformations, adding interactivity to the page. No matter what framework or library is used, they all eventually work through these objects. Knowledge of this topic is the basis of front-end development, on which everything else is strung.","kind":"basic","updated_at":"2026-01-20T11:39:33.431Z","language":"javascript","duration_cache":69660,"skills":["Bring web pages to life by adding interactivity to them","Interact with any elements on the page, select them or change them","Ensure JavaScript works universally in any browser","Handle forms correctly","Make AJAX requests to the server","Use JQuery to handle DOM"],"keywords":[],"lessons_count":18,"cover":"https://hexlet.io/rails/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6NjIyNSwicHVyIjoiYmxvYl9pZCJ9fQ==--0a602a0da6d2579638699e87f89fbee127cb30bb/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGciLCJyZXNpemVfdG9fZmlsbCI6WzYwMCw0MDBdfSwicHVyIjoidmFyaWF0aW9uIn19--39ba06fa99226096df9fc6bb31f84e1d29ea98e9/image.png"},"id":651,"slug":"js_dom_gem_puzzle_exercise","percent_of_success":"-"},{"exercise":{"id":2254,"slug":"js_dom_quotes_exercise","name":"Toto Robbins Quotes","state":"active","kind":"challenge","language":"javascript","locale":"en","has_web_view":true,"has_test_view":false,"reviewable":true,"readme":"## application.js\n\nImplement the logic of displaying Toto Robbins quotes\n\nEach click on the button in the web view should load a new quote from the backend and display it instead of the old one. All the necessary styling has already been added, examine it on a web view.\n\nQuery to the server:\n\n```javascript\nimport axios from 'axios';\n\n// Somewhere inside functions\nconst response = await axios.get(routes.randomQuotePath());\nconsole.log(response.data.quote); // here goes the quote\n```\n","prepared_readme":"## application.js\n\nImplement the logic of displaying Toto Robbins quotes\n\nEach click on the button in the web view should load a new quote from the backend and display it instead of the old one. All the necessary styling has already been added, examine it on a web view.\n\nQuery to the server:\n\n```javascript\nimport axios from 'axios';\n\n// Somewhere inside functions\nconst response = await axios.get(routes.randomQuotePath());\nconsole.log(response.data.quote); // here goes the quote\n```\n","has_solution":true,"entity_name":"Toto Robbins Quotes"},"course":{"start_lesson":{"exercise":null,"units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"links":[],"ordered_units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"id":3426,"slug":"intro","state":"approved","name":"Introduction","course_order":100,"goal":"Learn about the course and its objectives","self_study":null,"theory_video_provider":null,"theory_video_uid":null,"theory":"Today’s websites are highly interactive. Pages rarely reload, so we can change their content instantly.\n\nSoftware solutions have become so complex. Now we can open a browser and use programs like Photoshop, packages similar to Microsoft Office, or full-blown development environments such as our Hexlet editor.\n\nBrowser games are an enormous industry too. These games are no worse than regular desktop ones, thanks to hardware support.\n\nNone of this would be possible without JavaScript.\n\nJavaScript, which was originally used to add snowflakes to a web page, has become a powerful tool for professionals. To date, JavaScript is the only language that browsers can execute.\n\nBut a language is not enough to bring a page to life. The browser should provide a way to manage both the pages and the browser itself. Most of these features are standardized and described in the HTML5 specifications. Some of them are:\n\n* Manipulating page content\n* Managing appearance\n* Responding to user actions\n* Working with cookies\n* Controlling the browser's address bar, navigation, history\n* Interacting with the server\n* Video playback\n* Input/Output\n* Interacting with file systems and networks\n* 2D/3D drawing\n\nFrom the language’s point of view, most of these features look like global objects that you can interact with within the program. The most basic and important object in this system is the **DOM tree**.\n\nIn this course, we’ll learn how to implement JavaScript on a website, go through the fundamental ways to modify a page, get acquainted with polyfills, make our first Ajax request, and discover the world of events.\n\nAfter this course, you’ll try your hand at creating simple front-end games.\n\n## How to prepare for the course\n\nThis course is about animating pages in browsers using JavaScript. This course assumes that you’ve already studied JavaScript, either in Hexlet or on any other platform.\n"},"id":331,"slug":"js-dom","challenges_count":4,"name":"JS: DOM API","allow_indexing":true,"state":"approved","course_state":"finished","pricing_type":"paid","description":"The browser is a special environment in which JavaScript gets the opportunity to interact with loaded website pages. To do this, the browser provides special objects with a large number of methods. With their help, we can perform any HTML transformations, adding interactivity to the page. No matter what framework or library is used, they all eventually work through these objects. Knowledge of this topic is the basis of front-end development, on which everything else is strung.","kind":"basic","updated_at":"2026-01-20T11:39:33.431Z","language":"javascript","duration_cache":69660,"skills":["Bring web pages to life by adding interactivity to them","Interact with any elements on the page, select them or change them","Ensure JavaScript works universally in any browser","Handle forms correctly","Make AJAX requests to the server","Use JQuery to handle DOM"],"keywords":[],"lessons_count":18,"cover":"https://hexlet.io/rails/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6NjIyNSwicHVyIjoiYmxvYl9pZCJ9fQ==--0a602a0da6d2579638699e87f89fbee127cb30bb/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGciLCJyZXNpemVfdG9fZmlsbCI6WzYwMCw0MDBdfSwicHVyIjoidmFyaWF0aW9uIn19--39ba06fa99226096df9fc6bb31f84e1d29ea98e9/image.png"},"id":652,"slug":"js_dom_quotes_exercise","percent_of_success":"-"},{"exercise":{"id":2255,"slug":"js_dom_progress_exercise","name":"Progress","state":"active","kind":"challenge","language":"javascript","locale":"en","has_web_view":true,"has_test_view":false,"reviewable":true,"readme":"## src/application.js\n\nImplement and export as default the function that runs the code that fills the `<progress>` element by one percent in 1 second. After 100 seconds, the process should stop reaching its maximum.\n\nInitial state\n\n```html\n<progress value=\"0\" max=\"100\"></progress>\n```\n\nAfter one second\n\n```html\n<progress value=\"1\" max=\"100\"></progress>\n```\n\nTo change the *value* use the [setAttribute()](https://developer.mozilla.org/en-US/docs/Web/API/Element/setAttribute)\n\n### Tips\n\n* Complete the task using `setTimeout()` (`setInterval()` may break the tests)\n* [Progress](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/progress) element\n","prepared_readme":"## src/application.js\n\nImplement and export as default the function that runs the code that fills the `<progress>` element by one percent in 1 second. After 100 seconds, the process should stop reaching its maximum.\n\nInitial state\n\n```html\n<progress value=\"0\" max=\"100\"></progress>\n```\n\nAfter one second\n\n```html\n<progress value=\"1\" max=\"100\"></progress>\n```\n\nTo change the *value* use the [setAttribute()](https://developer.mozilla.org/en-US/docs/Web/API/Element/setAttribute)\n\n### Tips\n\n* Complete the task using `setTimeout()` (`setInterval()` may break the tests)\n* [Progress](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/progress) element\n","has_solution":true,"entity_name":"Progress"},"course":{"start_lesson":{"exercise":null,"units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"links":[],"ordered_units":[{"id":7705,"name":"theory","url":"/courses/js-dom/lessons/intro/theory_unit"}],"id":3426,"slug":"intro","state":"approved","name":"Introduction","course_order":100,"goal":"Learn about the course and its objectives","self_study":null,"theory_video_provider":null,"theory_video_uid":null,"theory":"Today’s websites are highly interactive. Pages rarely reload, so we can change their content instantly.\n\nSoftware solutions have become so complex. Now we can open a browser and use programs like Photoshop, packages similar to Microsoft Office, or full-blown development environments such as our Hexlet editor.\n\nBrowser games are an enormous industry too. These games are no worse than regular desktop ones, thanks to hardware support.\n\nNone of this would be possible without JavaScript.\n\nJavaScript, which was originally used to add snowflakes to a web page, has become a powerful tool for professionals. To date, JavaScript is the only language that browsers can execute.\n\nBut a language is not enough to bring a page to life. The browser should provide a way to manage both the pages and the browser itself. Most of these features are standardized and described in the HTML5 specifications. Some of them are:\n\n* Manipulating page content\n* Managing appearance\n* Responding to user actions\n* Working with cookies\n* Controlling the browser's address bar, navigation, history\n* Interacting with the server\n* Video playback\n* Input/Output\n* Interacting with file systems and networks\n* 2D/3D drawing\n\nFrom the language’s point of view, most of these features look like global objects that you can interact with within the program. The most basic and important object in this system is the **DOM tree**.\n\nIn this course, we’ll learn how to implement JavaScript on a website, go through the fundamental ways to modify a page, get acquainted with polyfills, make our first Ajax request, and discover the world of events.\n\nAfter this course, you’ll try your hand at creating simple front-end games.\n\n## How to prepare for the course\n\nThis course is about animating pages in browsers using JavaScript. This course assumes that you’ve already studied JavaScript, either in Hexlet or on any other platform.\n"},"id":331,"slug":"js-dom","challenges_count":4,"name":"JS: DOM API","allow_indexing":true,"state":"approved","course_state":"finished","pricing_type":"paid","description":"The browser is a special environment in which JavaScript gets the opportunity to interact with loaded website pages. To do this, the browser provides special objects with a large number of methods. With their help, we can perform any HTML transformations, adding interactivity to the page. No matter what framework or library is used, they all eventually work through these objects. Knowledge of this topic is the basis of front-end development, on which everything else is strung.","kind":"basic","updated_at":"2026-01-20T11:39:33.431Z","language":"javascript","duration_cache":69660,"skills":["Bring web pages to life by adding interactivity to them","Interact with any elements on the page, select them or change them","Ensure JavaScript works universally in any browser","Handle forms correctly","Make AJAX requests to the server","Use JQuery to handle DOM"],"keywords":[],"lessons_count":18,"cover":"https://hexlet.io/rails/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6NjIyNSwicHVyIjoiYmxvYl9pZCJ9fQ==--0a602a0da6d2579638699e87f89fbee127cb30bb/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGciLCJyZXNpemVfdG9fZmlsbCI6WzYwMCw0MDBdfSwicHVyIjoidmFyaWF0aW9uIn19--39ba06fa99226096df9fc6bb31f84e1d29ea98e9/image.png"},"id":653,"slug":"js_dom_progress_exercise","percent_of_success":"-"},{"exercise":{"id":2252,"slug":"js_dom_modal_exercise","name":"Modal window","state":"active","kind":"challenge","language":"javascript","locale":"en","has_web_view":true,"has_test_view":false,"reviewable":true,"readme":"## application.js\n\nImplement and export as default the function that controls modal windows.\n\n```html\n<button type=\"button\" class=\"btn btn-primary\" data-toggle=\"modal\" data-target=\"#exampleModal\">\n Launch demo modal\n</button>\n<div class=\"modal fade\" id=\"exampleModal\">\n <div class=\"modal-dialog\" role=\"document\">\n <div class=\"modal-content\">\n <div class=\"modal-header\">\n <h5 class=\"modal-title\" id=\"exampleModalLabel\">Modal title 1</h5>\n <button type=\"button\" class=\"close\" data-dismiss=\"modal\" aria-label=\"Close\">\n <span aria-hidden=\"true\">&times;</span>\n </button>\n </div>\n <div class=\"modal-body\">\n ...\n </div>\n </div>\n </div>\n</div>\n```\n\n* Buttons of modal windows are found using the *data-toggle=\"modal\"* selector\n* The window's ID is stored in the button's *data-target* attribute\n* To make the window pop up, you need to add the *show* class and set the *display* style to *block* in the element with a relevant *id* in a *data-target*\n* The cross available by the selector *data-dismiss=\"modal\"* hides the modal window. Clicking it has the opposite effect, the *show* class is removed, and *display* is set to *none*\n","prepared_readme":"## application.js\n\nImplement and export as default the function that controls modal windows.\n\n```html\n<button type=\"button\" class=\"btn btn-primary\" data-toggle=\"modal\" data-target=\"#exampleModal\">\n Launch demo modal\n</button>\n<div class=\"modal fade\" id=\"exampleModal\">\n <div class=\"modal-dialog\" role=\"document\">\n <div class=\"modal-content\">\n <div class=\"modal-header\">\n <h5 class=\"modal-title\" id=\"exampleModalLabel\">Modal title 1</h5>\n <button type=\"button\" class=\"close\" data-dismiss=\"modal\" aria-label=\"Close\">\n <span aria-hidden=\"true\">&times;</span>\n </button>\n </div>\n <div class=\"modal-body\">\n ...\n </div>\n </div>\n </div>\n</div>\n```\n\n* Buttons of modal windows are found using the *data-toggle=\"modal\"* selector\n* The window's ID is stored in the button's *data-target* attribute\n* To make the window pop up, you need to add the *show* class and set the *display* style to *block* in the element with a relevant *id* in a *data-target*\n* The cross available by the selector *data-dismiss=\"modal\"* hides the modal window. 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These games are no worse than regular desktop ones, thanks to hardware support.\n\nNone of this would be possible without JavaScript.\n\nJavaScript, which was originally used to add snowflakes to a web page, has become a powerful tool for professionals. To date, JavaScript is the only language that browsers can execute.\n\nBut a language is not enough to bring a page to life. The browser should provide a way to manage both the pages and the browser itself. Most of these features are standardized and described in the HTML5 specifications. Some of them are:\n\n* Manipulating page content\n* Managing appearance\n* Responding to user actions\n* Working with cookies\n* Controlling the browser's address bar, navigation, history\n* Interacting with the server\n* Video playback\n* Input/Output\n* Interacting with file systems and networks\n* 2D/3D drawing\n\nFrom the language’s point of view, most of these features look like global objects that you can interact with within the program. 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{.mantine-hidden-from-lg {display: none !important;}}@media (max-width: 87.99375em) {.mantine-visible-from-xl {display: none !important;}}@media (min-width: 88em) {.mantine-hidden-from-xl {display: none !important;}}</style><div style="--container-size:var(--container-size-lg);margin-top:var(--mantine-spacing-xl);height:100%" class="m_7485cace mantine-Container-root" data-size="lg" data-strategy="block"><style data-mantine-styles="inline">.__m__-_R_eub_{margin-bottom:var(--mantine-spacing-xs);}@media(min-width: 36em){.__m__-_R_eub_{margin-bottom:var(--mantine-spacing-xs);}}</style><div style="--group-gap:var(--mantine-spacing-md);--group-align:center;--group-justify:space-between;--group-wrap:wrap" class="m_4081bf90 mantine-Group-root __m__-_R_eub_"><style data-mantine-styles="inline">.__m__-_R_deub_{width:100%;}@media(min-width: 62em){.__m__-_R_deub_{width:66%;}}</style><div class="__m__-_R_deub_"><div style="--group-gap:var(--mantine-spacing-md);--group-align:center;--group-justify:start;--group-wrap:nowrap" class="m_4081bf90 mantine-Group-root"><h1 style="--title-fw:var(--mantine-h1-font-weight);--title-lh:var(--mantine-h1-line-height);--title-fz:var(--mantine-h1-font-size)" class="m_8a5d1357 mantine-Title-root" data-order="1">Course “JS: DOM API”</h1></div></div></div><style data-mantine-styles="inline">.__m__-_R_1iub_{width:100%;}@media(min-width: 62em){.__m__-_R_1iub_{width:66%;}}</style><div style="margin-bottom:var(--mantine-spacing-xl)" class="__m__-_R_1iub_"><div style="margin-bottom:var(--mantine-spacing-lg)" class=""></div><div style="margin-top:var(--mantine-spacing-lg)" class="mantine-hidden-from-md"><div style="--stack-gap:var(--mantine-spacing-xs);--stack-align:stretch;--stack-justify:flex-start" class="m_6d731127 mantine-Stack-root"><a style="--button-height:var(--button-height-md);--button-padding-x:var(--button-padding-x-md);--button-fz:var(--mantine-font-size-md);--button-color:var(--mantine-color-white);text-decoration:none" class="mantine-focus-auto m_849cf0da mantine-focus-auto mantine-active m_77c9d27d mantine-Button-root m_87cf2631 mantine-UnstyledButton-root m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-size="md" data-underline="hover" href="https://hexlet.io/subscription/new"><span class="m_80f1301b mantine-Button-inner"><span class="m_811560b9 mantine-Button-label">Subscribe</span></span></a><p style="color:var(--mantine-color-dimmed);font-size:var(--mantine-font-size-sm);text-align:center" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Access this and all courses with a subscription</p></div></div></div><style data-mantine-styles="inline">.__m__-_R_2iub_{--grid-gutter:var(--mantine-spacing-md);}</style><div class="m_410352e9 mantine-Grid-root __m__-_R_2iub_"><div class="m_dee7bd2f mantine-Grid-inner"><style data-mantine-styles="inline">.__m__-_R_dmiub_{--col-flex-grow:auto;--col-flex-basis:100%;--col-max-width:100%;}@media(min-width: 62em){.__m__-_R_dmiub_{--col-flex-grow:auto;--col-flex-basis:66.66666666666667%;--col-max-width:66.66666666666667%;}}</style><div class="m_96bdd299 mantine-Grid-col __m__-_R_dmiub_"><div style="margin-bottom:var(--mantine-spacing-xl);padding-inline:var(--mantine-spacing-xl);padding-block:var(--mantine-spacing-lg)" class="m_e615b15f mantine-Card-root m_1b7284a3 mantine-Paper-root" data-with-border="true"><p style="margin-bottom:var(--mantine-spacing-md);font-size:var(--mantine-font-size-h5);font-weight:bold" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">What's included</p><style data-mantine-styles="inline">.__m__-_R_ajddmiub_{--sg-spacing-x:var(--mantine-spacing-xs);--sg-spacing-y:var(--mantine-spacing-xs);--sg-cols:1;}@media(min-width: 48em){.__m__-_R_ajddmiub_{--sg-cols:2;}}</style><div class="m_2415a157 mantine-SimpleGrid-root __m__-_R_ajddmiub_"><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_1mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-check "><path d="M5 12l5 5l10 -10"></path></svg></div>18 lessons (video and/or text)</div><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_2mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-check "><path d="M5 12l5 5l10 -10"></path></svg></div>14 exercises in the simulator</div><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_3mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-check "><path d="M5 12l5 5l10 -10"></path></svg></div>51 verification tests</div><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_4mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-check "><path d="M5 12l5 5l10 -10"></path></svg></div>Self-study tasks</div><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_5mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-check "><path d="M5 12l5 5l10 -10"></path></svg></div>Extra materials</div><div style="align-items:center" class="m_8bffd616 mantine-Flex-root __m__-_R_6mqjddmiub_"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;margin-inline-end:var(--mantine-spacing-xs);color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div>18 extended materials</div></div></div><div style="margin-bottom:var(--mantine-spacing-xl)" class=""><h2 style="--title-fw:var(--mantine-h2-font-weight);--title-lh:var(--mantine-h2-line-height);--title-fz:var(--mantine-h2-font-size);margin-bottom:var(--mantine-spacing-md)" class="m_8a5d1357 mantine-Title-root" data-order="2">Description</h2><div class="m_d08caa0 mantine-Typography-root"><p>The browser is a special environment in which JavaScript gets the opportunity to interact with loaded website pages. To do this, the browser provides special objects with a large number of methods. With their help, we can perform any HTML transformations, adding interactivity to the page. No matter what framework or library is used, they all eventually work through these objects. Knowledge of this topic is the basis of front-end development, on which everything else is strung.</p></div></div><div style="margin-bottom:var(--mantine-spacing-xl)" class=""><h2 style="--title-fw:var(--mantine-h2-font-weight);--title-lh:var(--mantine-h2-line-height);--title-fz:var(--mantine-h2-font-size);margin-bottom:var(--mantine-spacing-md)" class="m_8a5d1357 mantine-Title-root" data-order="2">You will learn</h2><ul class="m_abbac491 mantine-List-root" data-type="none"><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Bring web pages to life by adding interactivity to them</span></div></li><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Interact with any elements on the page, select them or change them</span></div></li><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Ensure JavaScript works universally in any browser</span></div></li><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Handle forms correctly</span></div></li><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Make AJAX requests to the server</span></div></li><li style="margin-bottom:var(--mantine-spacing-xs);line-height:var(--mantine-line-height-sm)" class="m_abb6bec2 mantine-List-item" data-with-icon="true" data-centered="true"><div class="m_75cd9f71 mantine-List-itemWrapper"><span class="m_60f83e5b mantine-List-itemIcon"><div style="--ti-size:var(--ti-size-xs);--ti-bg:transparent;--ti-color:var(--mantine-color-indigo-light-color);--ti-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:inherit" class="m_7341320d mantine-ThemeIcon-root" data-variant="transparent" data-size="xs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="tabler-icon tabler-icon-plus "><path d="M12 5l0 14"></path><path d="M5 12l14 0"></path></svg></div></span><span class="mantine-List-itemLabel">Use JQuery to handle DOM</span></div></li></ul></div><div style="margin-bottom:var(--mantine-spacing-xl)" class=""><h2 style="--title-fw:var(--mantine-h2-font-weight);--title-lh:var(--mantine-h2-line-height);--title-fz:var(--mantine-h2-font-size);margin-bottom:var(--mantine-spacing-md)" class="m_8a5d1357 mantine-Title-root" data-order="2">Syllabus</h2><table style="--table-vertical-spacing:calc(0.4375rem * var(--mantine-scale))" class="m_b23fa0ef mantine-Table-table"><tbody class="m_b2404537 mantine-Table-tbody"><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">1</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/intro/theory_unit">Introduction</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn about the course and its objectives</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">2</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/js/theory_unit">JavaScript in the browser</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn to use js in the browser. Learn about the differences between server and client js.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">3</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/window/theory_unit">Global Window Object</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn why and how to use the window object</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">4</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/bom/theory_unit">BOM objects</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn the objects that allow you to control the browser through JavaScript</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">5</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/dom/theory_unit">What is DOM?</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how HTML differs from DOM</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">6</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/dom-hierarchy/theory_unit">Navigating the DOM Tree</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn the DOM tree structure. Learn to navigate it.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">7</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/search/theory_unit">Declarative DOM tree search</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn the search methods: getElementById, querySelector and others.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">8</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/devtools/theory_unit">DevTools</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to use the developer tools in the browser.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">9</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/tree-manipulating/theory_unit">Manipulating the Dom tree</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to change the DOM tree, add and remove elements.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">10</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/element-manipulating/theory_unit">Managing DOM Nodes</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn to modify elements. Understand the difference between attributes and properties.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">11</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/polyfills/theory_unit">Polyfills</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to level differences between browsers when working with the DOM</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">12</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/events/theory_unit">Introduction to events</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Explore the event model of the browser. Learn the basic events and their features of work.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">13</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/events-in-action/theory_unit">Events in practice</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to create interactive components</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">14</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/forms/theory_unit">Forms</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to handle forms</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">15</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/event-stages/theory_unit">Capturing and bubbling</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Understand the stages of events. Learn how to capture an event and stop it from propagating.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">16</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/document-events/theory_unit">Document Events</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn events that occur when loading and unloading a document.</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">17</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/ajax/theory_unit">AJAX</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn how to execute AJAX requests using the modern browser API - fetch</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p style="font-size:var(--mantine-font-size-h4)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">18</p></td><td style="padding-block:var(--mantine-spacing-lg)" class="m_4e7aa4ef mantine-Table-td"><a style="color:inherit;font-size:var(--mantine-font-size-h5)" class="mantine-focus-auto m_849cf0da m_b6d8b162 mantine-Text-root mantine-Anchor-root" data-underline="hover" href="/courses/js-dom/lessons/jquery/theory_unit">JQuery</a><p style="color:var(--mantine-color-dimmed)" class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Learn to use the jQuery library. Find out why it is required in every job, but companies discontinue to use it.</p></td></tr></tbody></table></div><div style="margin-bottom:var(--mantine-spacing-xl)" class=""><div style="--group-gap:var(--mantine-spacing-md);--group-align:center;--group-justify:flex-start;--group-wrap:wrap;margin-bottom:var(--mantine-spacing-md)" class="m_4081bf90 mantine-Group-root"><h2 style="--title-fw:var(--mantine-h2-font-weight);--title-lh:var(--mantine-h2-line-height);--title-fz:var(--mantine-h2-font-size)" class="m_8a5d1357 mantine-Title-root" data-order="2">Challenges</h2><button style="--ai-size:var(--ai-size-sm);--ai-bg:transparent;--ai-hover:transparent;--ai-color:var(--mantine-color-indigo-light-color);--ai-bd:calc(0.0625rem * var(--mantine-scale)) solid transparent;color:var(--mantine-color-dimmed)" class="mantine-focus-auto mantine-active m_8d3f4000 mantine-ActionIcon-root m_87cf2631 mantine-UnstyledButton-root" data-variant="transparent" data-size="sm" type="button" 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mantine-Text-root">Пятнашки</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">2</p></td><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Toto Robbins Quotes</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">3</p></td><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Progress</p></td></tr><tr class="m_4e7aa4fd mantine-Table-tr" data-with-row-border="true"><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">4</p></td><td class="m_4e7aa4ef mantine-Table-td"><p class="mantine-focus-auto m_b6d8b162 mantine-Text-root">Modal window</p></td></tr></tbody></table></div><div class=""><h2 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