diff --git a/index.html b/index.html
index a1aea97..88f6628 100644
--- a/index.html
+++ b/index.html
@@ -30,7 +30,7 @@ <h2 class="pictures__title  visually-hidden">Фотографии других 
       <section class="img-upload">
         <div class="img-upload__wrapper">
           <h2 class="img-upload__title  visually-hidden">Загрузка фотографии</h2>
-          <form class="img-upload__form" id="upload-select-image" autocomplete="off">
+          <form class="img-upload__form" id="upload-select-image" method="post" enctype="multipart/form-data" action="https://31.javascript.htmlacademy.pro/kekstagram" autocomplete="off">
 
             <!-- Изначальное состояние поля для загрузки изображения -->
             <fieldset class="img-upload__start">
@@ -233,7 +233,7 @@ <h2 class="success__title">Изображение успешно загруже
         <h2 class="data-error__title">Не удалось загрузить данные</h2>
       </section>
     </template>
-
+    <script src="vendor/pristine/pristine.min.js"></script>
     <script src="js/main.js" type="module"></script>
     <script src="js/functions.js"></script>
 </body>
diff --git a/js/check-hashtag-validity.js b/js/check-hashtag-validity.js
new file mode 100644
index 0000000..5ebbc31
--- /dev/null
+++ b/js/check-hashtag-validity.js
@@ -0,0 +1,30 @@
+const MAX_HASHTAG_COUNT = 5;
+const MAX_HASHTAG_LENGTH = 20;
+const HASHTAG_REGEXP = /^#[a-zа-яё0-9]+$/i;
+
+const normalizeHashtags = (value) => value
+  .trim()
+  .toLowerCase()
+  .split(/\s+/)
+  .filter((hashtag) => hashtag.length > 0);
+
+const hasValidHashtagCount = (value) =>
+  normalizeHashtags(value).length <= MAX_HASHTAG_COUNT;
+
+const hasValidHashtagLength = (value) =>
+  normalizeHashtags(value).every((hashtag) => hashtag.length <= MAX_HASHTAG_LENGTH);
+
+const hasValidHashtagFormat = (value) =>
+  normalizeHashtags(value).every((hashtag) => HASHTAG_REGEXP.test(hashtag));
+
+const hasUniqueHashtags = (value) => {
+  const hashtags = normalizeHashtags(value);
+  return hashtags.length === new Set(hashtags).size;
+};
+
+export {
+  hasValidHashtagCount,
+  hasValidHashtagLength,
+  hasValidHashtagFormat,
+  hasUniqueHashtags
+};
diff --git a/js/full-size-picture.js b/js/full-size-picture.js
index 12036b3..2a4e316 100644
--- a/js/full-size-picture.js
+++ b/js/full-size-picture.js
@@ -7,6 +7,16 @@ const likesCountNode = bigPictureNode.querySelector('.likes-count');
 const commentsCaptionNode = bigPictureNode.querySelector('.social__caption');
 const bigPictureCancelNode = bigPictureNode.querySelector('.big-picture__cancel');
 
+const onEscKeydown = (evt) => {
+  if (evt.key === 'Escape') {
+    evt.preventDefault();
+    clearComments();
+    bigPictureNode.classList.add('hidden');
+    document.body.classList.remove('modal-open');
+    document.removeEventListener('keydown', onEscKeydown);
+  }
+};
+
 const closeBigPicture = () => {
   clearComments();
   bigPictureNode.classList.add('hidden');
@@ -14,13 +24,6 @@ const closeBigPicture = () => {
   document.removeEventListener('keydown', onEscKeydown);
 };
 
-const onEscKeydown = (evt) => {
-  if (evt.key === 'Escape') {
-    evt.preventDefault();
-    closeBigPicture();
-  }
-};
-
 const onBigPictureCancelClick = (evt) => {
   evt.preventDefault();
   closeBigPicture();
diff --git a/js/main.js b/js/main.js
index b9e0f5c..ce58f80 100644
--- a/js/main.js
+++ b/js/main.js
@@ -1,5 +1,7 @@
 import { photos } from './create-array-photos.js';
 import { renderThumbnails } from './render-thumbnails.js';
+import { initUploadPhotoForm } from './upload-photo-form.js';
 
 renderThumbnails(photos);
+initUploadPhotoForm();
 
diff --git a/js/upload-photo-form.js b/js/upload-photo-form.js
new file mode 100644
index 0000000..2f97ffb
--- /dev/null
+++ b/js/upload-photo-form.js
@@ -0,0 +1,117 @@
+import {
+  hasValidHashtagCount,
+  hasValidHashtagLength,
+  hasValidHashtagFormat,
+  hasUniqueHashtags
+} from './check-hashtag-validity.js';
+
+const MAX_COMMENT_LENGTH = 140;
+
+const bodyNode = document.body;
+const uploadFormNode = document.querySelector('.img-upload__form');
+const uploadFileControl = uploadFormNode.querySelector('#upload-file');
+const uploadOverlayNode = uploadFormNode.querySelector('.img-upload__overlay');
+const uploadCancelButtonNode = uploadFormNode.querySelector('#upload-cancel');
+const hashtagsInputNode = uploadFormNode.querySelector('.text__hashtags');
+const descriptionInputNode = uploadFormNode.querySelector('.text__description');
+
+const pristine = new Pristine(uploadFormNode, {
+  classTo: 'img-upload__field-wrapper',
+  errorTextParent: 'img-upload__field-wrapper',
+  errorTextTag: 'div',
+  errorTextClass: 'img-upload__field-wrapper--error'
+});
+
+const isEscapeKey = (evt) => evt.key === 'Escape';
+
+const hasValidCommentLength = (value) => value.length <= MAX_COMMENT_LENGTH;
+
+const resetUploadPhotoForm = () => {
+  uploadFormNode.reset();
+  uploadFileControl.value = '';
+  pristine.reset();
+};
+
+const stopEscapePropagation = (evt) => {
+  if (isEscapeKey(evt)) {
+    evt.stopPropagation();
+  }
+};
+
+const onDocumentKeydown = (evt) => {
+  if (isEscapeKey(evt)) {
+    evt.preventDefault();
+    uploadOverlayNode.classList.add('hidden');
+    bodyNode.classList.remove('modal-open');
+    document.removeEventListener('keydown', onDocumentKeydown);
+    resetUploadPhotoForm();
+  }
+};
+
+const openUploadPhotoForm = () => {
+  uploadOverlayNode.classList.remove('hidden');
+  bodyNode.classList.add('modal-open');
+  document.addEventListener('keydown', onDocumentKeydown);
+};
+
+const closeUploadPhotoForm = () => {
+  uploadOverlayNode.classList.add('hidden');
+  bodyNode.classList.remove('modal-open');
+  document.removeEventListener('keydown', onDocumentKeydown);
+  resetUploadPhotoForm();
+};
+
+const onUploadFileControlChange = () => {
+  openUploadPhotoForm();
+};
+
+const onUploadCancelButtonClick = (evt) => {
+  evt.preventDefault();
+  closeUploadPhotoForm();
+};
+
+const onUploadFormSubmit = (evt) => {
+  if (!pristine.validate()) {
+    evt.preventDefault();
+  }
+};
+
+pristine.addValidator(
+  hashtagsInputNode,
+  hasValidHashtagCount,
+  'Нельзя указать больше пяти хэштегов'
+);
+
+pristine.addValidator(
+  hashtagsInputNode,
+  hasValidHashtagLength,
+  'Максимальная длина одного хэштега — 20 символов'
+);
+
+pristine.addValidator(
+  hashtagsInputNode,
+  hasValidHashtagFormat,
+  'Хэштег должен начинаться с # и содержать только буквы и цифры'
+);
+
+pristine.addValidator(
+  hashtagsInputNode,
+  hasUniqueHashtags,
+  'Хэштеги не должны повторяться'
+);
+
+pristine.addValidator(
+  descriptionInputNode,
+  hasValidCommentLength,
+  'Длина комментария не может составлять больше 140 символов'
+);
+
+const initUploadPhotoForm = () => {
+  uploadFileControl.addEventListener('change', onUploadFileControlChange);
+  uploadCancelButtonNode.addEventListener('click', onUploadCancelButtonClick);
+  uploadFormNode.addEventListener('submit', onUploadFormSubmit);
+  hashtagsInputNode.addEventListener('keydown', stopEscapePropagation);
+  descriptionInputNode.addEventListener('keydown', stopEscapePropagation);
+};
+
+export { initUploadPhotoForm };