diff --git a/src/assets/favorites/books/book-2.jpeg b/src/assets/favorites/books/book-2.jpeg
deleted file mode 100644
index fab0cf6..0000000
Binary files a/src/assets/favorites/books/book-2.jpeg and /dev/null differ
diff --git a/src/assets/favorites/books/book-2.jpg b/src/assets/favorites/books/book-2.jpg
new file mode 100644
index 0000000..9eaf279
Binary files /dev/null and b/src/assets/favorites/books/book-2.jpg differ
diff --git a/src/data/config.ts b/src/data/config.ts
index 463b18c..b0816fa 100644
--- a/src/data/config.ts
+++ b/src/data/config.ts
@@ -10,7 +10,7 @@ const config = {
       now: 'now',
     },
   },
-  seo: {
+  meta: {
     title: 'Mark Freeman - Senior React Developer',
     description:
       'Lorem ipsum dolor sit amet, consectetur adipiscing elit. In sodales ac dui at vestibulum. In condimentum metus id dui tincidunt, in blandit mi vehicula.',
diff --git a/src/data/sections/favorites-section.data.ts b/src/data/sections/favorites-section.data.ts
index 503869f..bddc896 100644
--- a/src/data/sections/favorites-section.data.ts
+++ b/src/data/sections/favorites-section.data.ts
@@ -18,7 +18,7 @@ const favoritesSectionData = {
         url: 'https://www.goodreads.com/book/show/4099.The_Pragmatic_Programmer',
       },
       {
-        image: 'https://m.media-amazon.com/images/I/61aFldsgAmL._SY344_BO1,204,203,200_QL70_ML2_.jpg',
+        image: import('@/assets/favorites/books/book-2.jpg'),
         title: 'Domain-Driven Design: Tackling Complexity in the Heart of Software',
         author: 'Eric Evans',
         url: 'https://www.goodreads.com/book/show/179133.Domain_Driven_Design',
diff --git a/src/types/config/i18n-config.types.ts b/src/types/config/i18n-config.types.ts
index a90540d..0e2ce80 100644
--- a/src/types/config/i18n-config.types.ts
+++ b/src/types/config/i18n-config.types.ts
@@ -1,9 +1,23 @@
 import type { Locale } from 'date-fns';
 
 export interface I18nConfig {
+  /**
+   * Language code used for date formatting, translations, and value of the page `lang` attribute.
+   */
   locale: Locale;
+
+  /**
+   * Date format used when displaying date ranges in some sections.
+   */
   dateFormat: string;
+
+  /**
+   * List of translations used in the application.
+   */
   translations: {
+    /**
+     * Used in date ranges to represent the current date.
+     */
     now: string;
   };
 }
diff --git a/src/types/config/meta-config.types.ts b/src/types/config/meta-config.types.ts
new file mode 100644
index 0000000..5cff761
--- /dev/null
+++ b/src/types/config/meta-config.types.ts
@@ -0,0 +1,55 @@
+export interface MetaConfig {
+  /**
+   * [WEB] Page title.
+   *
+   * Displayed as browser tab title and in search results.
+   * It's recommended to keep it between 30 and 60 characters.
+   *
+   * @see https://www.screamingfrog.co.uk/learn-seo/page-title
+   */
+  title: string;
+
+  /**
+   * [WEB] Page description.
+   *
+   * Displayed under the title in search results.
+   * It's recommended to keep it between 70 and 155 characters.
+   *
+   * @see https://www.screamingfrog.co.uk/learn-seo/meta-description
+   */
+  description: string;
+
+  /**
+   * [WEB] URL or path to the page's favicon.
+   *
+   * Specified icon will be displayed next to the page title in browser tab.
+   */
+  favicon: string;
+
+  /**
+   * [WEB] Title used in open graph links.
+   *
+   * If not specified, the title property will be used.
+   *
+   * @see https://ahrefs.com/blog/open-graph-meta-tags
+   */
+  ogTitle?: string;
+
+  /**
+   * [WEB] Description used in open graph links.
+   *
+   * If not specified, the description property will be used.
+   *
+   * @see https://ahrefs.com/blog/open-graph-meta-tags
+   */
+  ogDescription?: string;
+
+  /**
+   * [WEB] Image used in open graph links.
+   *
+   * It's recommended to keep it between 30 and 60 characters.
+   *
+   * @see https://ahrefs.com/blog/open-graph-meta-tags
+   */
+  ogImage?: string;
+}
diff --git a/src/types/config/pdf-config.types.ts b/src/types/config/pdf-config.types.ts
index 9112955..f1cf9f3 100644
--- a/src/types/config/pdf-config.types.ts
+++ b/src/types/config/pdf-config.types.ts
@@ -1,3 +1,8 @@
 export interface PdfConfig {
+  /**
+   * [PDF] Displays footer with specified content on each PDF page.
+   *
+   * You can use it to add the data processing clause.
+   */
   footer?: string;
 }
diff --git a/src/types/config/seo-config.types.ts b/src/types/config/seo-config.types.ts
deleted file mode 100644
index d1a7be8..0000000
--- a/src/types/config/seo-config.types.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-export interface SeoConfig {
-  title: string;
-  description: string;
-  favicon: string;
-  ogTitle?: string;
-  ogDescription?: string;
-  ogImage?: string;
-}
diff --git a/src/types/data.ts b/src/types/data.ts
index b42d387..5dbfd77 100644
--- a/src/types/data.ts
+++ b/src/types/data.ts
@@ -1,6 +1,6 @@
 import type { I18nConfig } from './config/i18n-config.types';
 import type { PdfConfig } from './config/pdf-config.types';
-import type { SeoConfig } from './config/seo-config.types';
+import type { MetaConfig } from './config/meta-config.types';
 import type { EducationSection } from './sections/education-section.types';
 import type { ExperienceSection } from './sections/experience-section.types';
 import type { FavoritesSection } from './sections/favorites-section.types';
@@ -10,22 +10,70 @@ import type { SkillsSection } from './sections/skills-section.types';
 import type { TestimonialsSection } from './sections/testimonials-section.types';
 
 export interface Config {
-  seo: SeoConfig;
+  /**
+   * [WEB] Page metadata used for SEO and social media sharing.
+   */
+  meta: MetaConfig;
+
+  /**
+   * Language and date display configuration.
+   */
   i18n: I18nConfig;
+
+  /**
+   * [PDF] Configuration of the pdf generation.
+   */
   pdf?: PdfConfig;
 }
 
 export interface Sections {
+  /**
+   * Basic information about you.
+   */
   main: MainSection;
+
+  /**
+   * Grouped lists of your skills.
+   */
   skills: SkillsSection;
+
+  /**
+   * Your employment history.
+   */
   experience: ExperienceSection;
+
+  /**
+   * Your projects and initiatives.
+   */
   portfolio: PortfolioSection;
+
+  /**
+   * Your education degrees and certifications.
+   */
   education: EducationSection;
+
+  /**
+   * [WEB] Recommendations from your previous employers and people you worked with.
+   */
   testimonials: TestimonialsSection;
+
+  /**
+   * [WEB] List of sources you use to gain knowledge and inspiration.
+   */
   favorites: FavoritesSection;
 }
 
+/**
+ * All data used to generate the cv.
+ */
 export interface Data {
+  /**
+   * Global configuration of the web and pdf versions of the cv.
+   */
   config: Config;
+
+  /**
+   * Configurations for the particular sections of the cv.
+   */
   sections: Sections;
 }
diff --git a/src/types/sections/education-section.types.ts b/src/types/sections/education-section.types.ts
index d08f836..3c41207 100644
--- a/src/types/sections/education-section.types.ts
+++ b/src/types/sections/education-section.types.ts
@@ -1,13 +1,35 @@
 import type { DateRange, Description, LinkButton, Section } from '../shared';
 
 export interface Diploma {
+  /**
+   * Name of the certificate or the degree you got.
+   */
   title: string;
+
+  /**
+   * Name of the institution that issued the certificate or degree.
+   */
   institution: string;
+
+  /**
+   * Date range when you were studying in the institution.
+   */
   dates: DateRange;
+
+  /**
+   * A short overview of your studies. You can write it as a paragraph (string) or as a list of bullet points (string[]).
+   */
   description: Description;
+
+  /**
+   * [WEB] Links related to your studies (e.g. course/university website, link to realized project).
+   */
   links: LinkButton[];
 }
 
 export interface EducationSection extends Section {
+  /**
+   * List of your diplomas, certificates, .etc. Start with the most recent one.
+   */
   diplomas: Diploma[];
 }
diff --git a/src/types/sections/experience-section.types.ts b/src/types/sections/experience-section.types.ts
index b1bb4cc..37c7726 100644
--- a/src/types/sections/experience-section.types.ts
+++ b/src/types/sections/experience-section.types.ts
@@ -1,14 +1,41 @@
 import type { DateRange, Description, LinkButton, Section, TagsList } from '../shared';
 
 export interface Job {
+  /**
+   * Your position in the company.
+   */
   role: string;
+
+  /**
+   * Name of the company.
+   */
   company: string;
+
+  /**
+   * Date range when you were working in the company.
+   */
   dates: DateRange;
+
+  /**
+   * A short overview of your job. You can write it as a paragraph (string) or as a list of bullet points (string[]).
+   */
   description: Description;
+
+  /**
+   * Any information that you want to highlight.
+   * We recommend to describe the technologies used in the project.
+   */
   tagsList: TagsList;
+
+  /**
+   * [WEB] Links related to your job (e.g. production app, company's website, project website).
+   */
   links: LinkButton[];
 }
 
 export interface ExperienceSection extends Section {
+  /**
+   * List of your jobs in a chronological order. Start with the most recent one.
+   */
   jobs: Job[];
 }
diff --git a/src/types/sections/favorites-section.types.ts b/src/types/sections/favorites-section.types.ts
index 5351c0c..904a6a9 100644
--- a/src/types/sections/favorites-section.types.ts
+++ b/src/types/sections/favorites-section.types.ts
@@ -1,39 +1,129 @@
 import type { Photo, Section } from '../shared';
 
 export interface Book {
+  /**
+   * [WEB] Book title.
+   */
   title: string;
+
+  /**
+   * [WEB] Book cover.
+   *
+   * **Ratio**: 3:4
+   *
+   * **Display size**: 300x400px
+   */
   image: Photo;
+
+  /**
+   * [WEB] Full name of the book author.
+   */
   author: string;
+
+  /**
+   * [WEB] Website to buy the book or read more about it.
+   */
   url: string;
 }
 
 export interface Person {
+  /**
+   * [WEB] Full name of the person.
+   */
   name: string;
+
+  /**
+   * [WEB] Photo of the person.
+   *
+   * **Ratio**: 1:1
+   *
+   * **Display size**: 200x200px
+   */
   image: Photo;
+
+  /**
+   * [WEB] Main website related to the person.
+   */
   url?: string;
 }
 
 export interface Video {
+  /**
+   * [WEB] Title of the video.
+   */
   title: string;
+
+  /**
+   * [WEB] Thumbnail of the video.
+   *
+   * **Ratio**: 16:9
+   *
+   * **Display size**: 448x252px
+   */
   image: Photo;
+
+  /**
+   * [WEB] Link to the video.
+   */
   url: string;
 }
 
 export interface Media {
+  /**
+   * [WEB] Title of the media.
+   */
   title: string;
+
+  /**
+   * [WEB] Type of the media (e.g. podcast, blog, newsletter, YouTube channel, .etc).
+   */
   type: string;
+
+  /**
+   * [WEB] Logo of the media.
+   *
+   * **Ratio**: 1:1
+   *
+   * **Display size**: 200x200px
+   */
   image: Photo;
+
+  /**
+   * [WEB] URL to the main website related to the media.
+   */
   url: string;
 }
 
 export interface SubSection<Data = unknown> {
+  /**
+   * [WEB] Title that will be displayed above the list of items.
+   */
   title: string;
+
+  /**
+   * [WEB] List of items to display within the subsection.
+   */
   data: Data[];
 }
 
 export interface FavoritesSection extends Section {
+  /**
+   * [WEB] List of your favorite books.
+   */
   books?: SubSection<Book>;
+
+  /**
+   * [WEB] List of the people that inspire you.
+   */
   people?: SubSection<Person>;
+
+  /**
+   * [WEB] List of the videos you learned the most from.
+   */
   videos?: SubSection<Video>;
+
+  /**
+   * [WEB] List of other media types that helps you to growth in your field.
+   */
   medias?: SubSection<Media>;
 }
diff --git a/src/types/sections/main-section.types.ts b/src/types/sections/main-section.types.ts
index 64ff592..fc9f4af 100644
--- a/src/types/sections/main-section.types.ts
+++ b/src/types/sections/main-section.types.ts
@@ -1,13 +1,58 @@
 import type { DownloadButton, Photo, LabelledValue, LinkButton, Section, Tag } from '../shared';
 
 export interface MainSection extends Section {
+  /**
+   * Your image.
+   *
+   * **Ratio**: 1:1
+   *
+   * **Display size**: 208x208px
+   */
   image: Photo;
+
+  /**
+   * Your name.
+   */
   fullName: string;
+
+  /**
+   * Your current role.
+   */
   role: string;
+
+  /**
+   * Label-value pairs with some key details about you.
+   *
+   * E.g. phone, email, location, expected salary.
+   */
   details: LabelledValue[];
+
+  /**
+   * [PDF] Labeled-value pairs that will be used in the PDF version of your resume.
+   *
+   * You can use it to add your social media profiles as those listed under the `links` property aren't used in the PDF.
+   *
+   * If not provided, the `details` will be used instead.
+   */
   pdfDetails?: LabelledValue[];
+
+  /**
+   * A short overview of you and your experience.
+   */
   description: string;
+
+  /**
+   * [WEB] Any information that you want to highlight.
+   */
   tags: Tag[];
+
+  /**
+   * [WEB] A button that will be used to download your resume.
+   */
   action: DownloadButton;
+
+  /**
+   * [WEB] Your social media profiles.
+   */
   links: LinkButton[];
 }
diff --git a/src/types/sections/portfolio-section.types.ts b/src/types/sections/portfolio-section.types.ts
index 23f525d..ec6f523 100644
--- a/src/types/sections/portfolio-section.types.ts
+++ b/src/types/sections/portfolio-section.types.ts
@@ -1,16 +1,59 @@
 import type { DateRange, Photo, LabelledValue, LinkButton, Section, TagsList, Description } from '../shared';
 
 export interface Project {
+  /**
+   * Name of the project.
+   */
   name: string;
+
+  /**
+   * [WEB] Logo of the project.
+   *
+   * **Ratio**: 1:1
+   *
+   * **Display size**: 120x120px
+   */
   image: Photo;
+
+  /**
+   * Date range when you were working on the project.
+   */
   dates: DateRange;
+
+  /**
+   * Label-value pairs with some key details about the project.
+   */
   details: LabelledValue[];
+
+  /**
+   * [PDF] Labeled-value pairs that will be used in the PDF version of your resume.
+   *
+   * You can use it to add some links related to your project as those listed under the `links` property aren't used in the PDF.
+   *
+   * If not provided, the `details` will be used instead.
+   */
   pdfDetails?: LabelledValue[];
+
+  /**
+   * A short overview of the project. You can write it as a paragraph (string) or as a list of bullet points (string[]).
+   */
   description: Description;
+
+  /**
+   * Any information that you want to highlight.
+   * We recommend to describe the technologies used in the project.
+   */
   tagsList: TagsList;
+
+  /**
+   * [WEB] Links related to your project (e.g. GitHub repository, live demo, mockups).
+   */
   links: LinkButton[];
 }
 
 export interface PortfolioSection extends Section {
+  /**
+   * List of your projects in a chronological order. Start with the most recent one.
+   */
   projects: Project[];
 }
diff --git a/src/types/sections/skills-section.types.ts b/src/types/sections/skills-section.types.ts
index 6dffbcd..b5d08f2 100644
--- a/src/types/sections/skills-section.types.ts
+++ b/src/types/sections/skills-section.types.ts
@@ -5,14 +5,30 @@ export interface Skill extends Tag {}
 export type SkillLevel = 1 | 2 | 3 | 4 | 5;
 
 export interface LevelledSkill extends Skill {
+  /**
+   * Your level of skill proficiency in a 1-5 scale.
+   */
   level: SkillLevel;
 }
 
 export interface SkillSet {
+  /**
+   * Title that will be displayed above the list of skills.
+   */
   title: string;
+
+  /**
+   * List of skills with or without levels.
+   *
+   * If you want to displays skills with levels, we recommend to also provide the `description` property.
+   * This way anyone viewing your resume will know what is the meaning of each level.
+   */
   skills: Skill[] | LevelledSkill[];
 }
 
 export interface SkillsSection extends Section {
+  /**
+   * Grouped lists of your skills.
+   */
   skillSets: SkillSet[];
 }
diff --git a/src/types/sections/testimonials-section.types.ts b/src/types/sections/testimonials-section.types.ts
index cf8fe9e..9f1b2e3 100644
--- a/src/types/sections/testimonials-section.types.ts
+++ b/src/types/sections/testimonials-section.types.ts
@@ -1,13 +1,39 @@
 import type { Photo, LinkButton, Section } from '../shared';
 
 export interface Testimonial {
+  /**
+   * [WEB] Photo of the testimonial author.
+   *
+   * **Ratio**: 1:1
+   *
+   * **Display size**: 56x56px
+   */
   image: Photo;
+
+  /**
+   * [WEB] Full name of the testimonial author.
+   */
   author: string;
+
+  /**
+   * [WEB] Your relation to the testimonial author (e.g. supervisor, colleague, subordinate).
+   */
   relation: string;
+
+  /**
+   * [WEB] Content of the testimonial.
+   */
   content: string;
+
+  /**
+   * [WEB] Social media (e.g. LinkedIn profile, website) of the testimonial author.
+   */
   links: LinkButton[];
 }
 
 export interface TestimonialsSection extends Section {
+  /**
+   * [WEB] List of your testimonials in a chronological order. Start with the most recent one.
+   */
   testimonials: Testimonial[];
 }
diff --git a/src/types/shared.ts b/src/types/shared.ts
index 85fab3d..16eb30f 100644
--- a/src/types/shared.ts
+++ b/src/types/shared.ts
@@ -1,52 +1,162 @@
 import type { CircleFlags, Fa6Brands, Fa6Solid, Ri, SimpleIcons } from 'iconify-icon-names';
 
+/**
+ * Name of the icon from the iconify library.
+ *
+ * @see https://icon-sets.iconify.design
+ */
 export type IconName = Fa6Brands | Fa6Solid | SimpleIcons | CircleFlags | Ri;
 
+/**
+ * - Dynamic import of the image from `src/assets` folder. Recommended as it enables image optimization.
+ * - Path to the image placed in the `public` folder.
+ * - URL of the image stored online.
+ */
 export type Photo = Promise<{ default: ImageMetadata }> | string;
 
+/**
+ * Two date objects representing some time period.
+ *
+ * If the second date is `null`, it means that the period is still ongoing.
+ * In such case, the translation from `config.i18n.translations.now` will be used.
+ */
 export type DateRange = [from: Date, to: Date | null];
 
+/**
+ * If a string is provided, it will be displayed as a single justified paragraph.
+ * If an array of strings is provided it will be displayed as a list.
+ */
 export type Description = string | string[];
 
 export interface SectionConfig {
+  /**
+   * Name displayed as a section header (except for the main section).
+   *
+   * [WEB] Content of the tooltip displayed when someone hovers over the section in the sidebar.
+   */
   title: string;
+
+  /**
+   * [WEB] URL hash used to navigate to the section.
+   */
   slug: string;
+
+  /**
+   * [WEB] Icon used in sidebar navigation to represent the section.
+   */
   icon: IconName;
+
+  /**
+   * Should section be displayed on the page.
+   */
   visible: boolean;
 }
 
 export interface Section {
+  /**
+   * Base information about the section.
+   */
   config: SectionConfig;
 }
 
 export interface LabelledValue {
+  /**
+   * Bolder text displayed on the left side of the value.
+   */
   label: string;
+
+  /**
+   * Text displayed on the right side.
+   * If a list of strings provided, they will be separated by a comma.
+   */
   value: string | string[];
+
+  /**
+   * URL that will be opened in a new tab, when the value is clicked.
+   */
   url?: string;
+
+  /**
+   * [PDF] When labelled value is displayed in a grid, it will span the whole row.
+   */
   fullRow?: boolean;
 }
 
 export interface Tag {
+  /**
+   * Text displayed within the tag.
+   */
   name: string;
+
+  /**
+   * [WEB] Icon displayed next to the tag text.
+   */
   icon?: IconName;
+
+  /**
+   * [WEB] Color of the icon. By default, the color is inherited from the text.
+   */
   iconColor?: string;
+
+  /**
+   * [WEB] URL that will be opened in a new tab, when the tag is clicked.
+   */
   url?: string;
+
+  /**
+   * [WEB] Text displayed in the tooltip when someone hovers over the tag.
+   */
   description?: string;
 }
 
 export interface TagsList {
+  /**
+   * [PDF] Text displayed before the list of tags.
+   */
   title: string;
+
+  /**
+   * Tags to be displayed within the list.
+   * [WEB] Tags are displayed as gray blocks. All tag properties are used.
+   * [PDF] Tags are displayed comma separated list. Only the `name` property are used.
+   */
   tags: Tag[];
 }
 
 export interface DownloadButton {
+  /**
+   * [WEB] Text displayed within the download button.
+   */
   label: string;
+
+  /**
+   * [WEB] URL or path to the CV file.
+   */
   url: string;
+
+  /**
+   * [WEB] Name of the file that will be downloaded.
+   *
+   * If not specified, the original file name will be used and file will open in a PDF viewer in some browsers.
+   *
+   * If specified, the file will be downloaded immediately (without preview) in all browsers.
+   */
   downloadedFileName?: string;
 }
 
 export interface LinkButton {
+  /**
+   * [WEB] Name displayed in the tooltip when someone hovers over the button.
+   */
   name: string;
+
+  /**
+   * [WEB] Icon displayed within the button.
+   */
   icon: IconName;
+
+  /**
+   * [WEB] URL that will be opened in a new tab, when the button is clicked.
+   */
   url: string;
 }
diff --git a/src/web/components/layout.astro b/src/web/components/layout.astro
index 9d12eae..f6fe997 100644
--- a/src/web/components/layout.astro
+++ b/src/web/components/layout.astro
@@ -2,9 +2,9 @@
 import type { Data } from '@/types/data';
 import Analytics from '@/web/analytics/analytics.astro';
 
-export interface Props extends Pick<Data['config'], 'seo' | 'i18n'> {}
+export interface Props extends Pick<Data['config'], 'meta' | 'i18n'> {}
 
-const { seo, i18n } = Astro.props;
+const { meta, i18n } = Astro.props;
 ---
 
 <!DOCTYPE html>
@@ -13,12 +13,12 @@ const { seo, i18n } = Astro.props;
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width" />
     <meta name="generator" content={Astro.generator} />
-    <title>{seo.title}</title>
-    <meta name="description" content={seo.description} />
-    <link rel="icon" type="image/svg+xml" href={seo.favicon} />
-    <meta property="og:title" content={seo.ogTitle ?? seo.title} />
-    <meta property="og:description" content={seo.ogDescription ?? seo.description} />
-    {seo.ogImage && <meta property="og:image" content={seo.ogImage} />}
+    <title>{meta.title}</title>
+    <meta name="description" content={meta.description} />
+    <link rel="icon" type="image/svg+xml" href={meta.favicon} />
+    <meta property="og:title" content={meta.ogTitle ?? meta.title} />
+    <meta property="og:description" content={meta.ogDescription ?? meta.description} />
+    {meta.ogImage && <meta property="og:image" content={meta.ogImage} />}
     <script is:inline>
       const theme = (() => {
         if (typeof localStorage !== 'undefined' && localStorage.getItem('theme')) {
diff --git a/src/web/utils/hash-state.ts b/src/web/utils/hash-state.ts
index 9e21286..44a75f0 100644
--- a/src/web/utils/hash-state.ts
+++ b/src/web/utils/hash-state.ts
@@ -4,7 +4,11 @@ import { isServer } from './env';
 const getInitialHash = () => {
   if (isServer) return '';
 
-  return window.location.hash || `#${sections.main.config.slug}`;
+  const firstVisibleSection = Object.values(sections).find((section) => section.config.visible);
+
+  if (!firstVisibleSection) return '';
+
+  return window.location.hash || `#${firstVisibleSection.config.slug}`;
 };
 
 const createHashState = () => {