@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Poppins:wght@400;500;600;700;800&display=swap');

/* ===========================
   CSS VARIABLES & ROOT STYLES
   =========================== */
:root {
    /* Light Mode Colors */
    --primary-color-light: #0073aa;
    --secondary-color-light: #00557f;
    --accent-color-light: #4caf50;
    --background-color-light: #ffffff;
    --card-background-light: #ffffff;
    --text-color-light: #212529;
    --text-muted-light: #5f6368;
    --border-color-light: #dee2e6;
    --code-background-light: #f1f3f5;
    --header-bg-light: #ffffff;
    --navbar-bg-light: #ffffff;
    --sidebar-bg-light: #ffffff;
    --link-color-light: var(--primary-color-light);
    --link-hover-light: var(--secondary-color-light);

    /* Dark Mode Colors */
    --primary-color-dark: #56aeff;
    --secondary-color-dark: #368fdd;
    --accent-color-dark: #66bb6a;
    --background-color-dark: #121212;
    --card-background-dark: #1e1e1e;
    --text-color-dark: #e0e0e0;
    --text-muted-dark: #9e9e9e;
    --border-color-dark: #3a3a3a;
    --code-background-dark: #2a2a2a;
    --header-bg-dark: #1e1e1e;
    --navbar-bg-dark: #1e1e1e;
    --sidebar-bg-dark: #1e1e1e;
    --link-color-dark: var(--primary-color-dark);
    --link-hover-dark: var(--secondary-color-dark);
}

/* ===========================
   BASE STYLES
   =========================== */
* {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    background-color: var(--background-color-light);
    color: var(--text-color-light);
    transition: background-color 0.3s, color 0.3s;
}

/* ===========================
   DARK MODE STYLES
   =========================== */
body.dark-mode {
    background-color: var(--background-color-dark);
    color: var(--text-color-dark);
}

body.dark-mode .top-utility-navbar {
    background-color: var(--navbar-bg-dark);
    border-bottom-color: var(--border-color-dark);
}

body.dark-mode .top-utility-navbar a,
body.dark-mode .top-utility-navbar .navbar-brand {
    color: var(--text-color-dark);
}

body.dark-mode .top-utility-navbar a:hover {
    color: var(--primary-color-dark);
}

body.dark-mode #theme-toggle-button svg {
    stroke: var(--text-color-dark);
}

body.dark-mode #theme-toggle-button:hover svg {
    stroke: var(--primary-color-dark);
}

body.dark-mode .page-main-header {
    background: var(--header-bg-dark);
    color: var(--text-color-dark);
    border-bottom: 1px solid var(--border-color-dark);
}

body.dark-mode .page-main-header h1 {
    color: var(--primary-color-dark);
}

body.dark-mode .sidebar {
    background-color: var(--sidebar-bg-dark);
    border-right-color: var(--border-color-dark);
}

body.dark-mode .sidebar h3 {
    color: var(--primary-color-dark);
    border-bottom-color: var(--secondary-color-dark);
}

body.dark-mode #toc-list>li>a {
    color: var(--text-muted-dark);
}

body.dark-mode #toc-list>li>a:hover {
    color: var(--primary-color-dark);
}

body.dark-mode #toc-list>li>a.active {
    color: var(--primary-color-dark);
    font-weight: 600;
}

body.dark-mode #toc-list ul li a {
    color: #aaaaaa;
}

body.dark-mode #toc-list ul li a:hover {
    color: var(--secondary-color-dark);
}

body.dark-mode #toc-list ul li a.active {
    color: var(--secondary-color-dark);
}

body.dark-mode h2 {
    color: var(--primary-color-dark);
    border-bottom-color: var(--secondary-color-dark);
}

body.dark-mode h3 {
    color: var(--secondary-color-dark);
}

body.dark-mode h4 {
    color: var(--primary-color-dark);
}

body.dark-mode .feature-item {
    background-color: var(--background-color-dark);
    border-color: var(--border-color-dark);
}

body.dark-mode .feature-item h4 {
    color: var(--primary-color-dark);
}

body.dark-mode code {
    background-color: var(--code-background-dark);
    color: #f0f0f0;
}

body.dark-mode pre {
    background-color: var(--code-background-dark);
    border: 1px solid var(--border-color-dark);
}

body.dark-mode pre code {
    color: #f0f0f0;
}

body.dark-mode a {
    color: var(--link-color-dark);
}

body.dark-mode a:hover {
    color: var(--link-hover-dark);
}

body.dark-mode footer {
    border-top-color: var(--border-color-dark);
    color: var(--text-muted-dark);
}

body.dark-mode .accordion-header {
    color: var(--text-color-dark);
    background-color: var(--background-color-dark);
}

body.dark-mode .accordion-header:hover {
    color: var(--primary-color-dark);
}

body.dark-mode .share-dropdown {
    background-color: var(--card-background-dark);
    border-color: var(--border-color-dark);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

body.dark-mode .share-dropdown-item {
    color: var(--text-color-dark);
}

body.dark-mode .share-dropdown-item:hover {
    background-color: var(--code-background-dark);
    color: var(--primary-color-dark);
}

body.dark-mode .copy-feedback {
    color: var(--accent-color-dark);
}

body.dark-mode #page-share-button:hover {
    color: var(--primary-color-dark);
    background-color: var(--code-background-dark);
    border-color: var(--primary-color-dark);
    transform: translateY(-1px);
}

body.dark-mode .feature-item:hover {
    box-shadow: 0 4px 8px rgba(255, 255, 255, 0.1);
}

body.dark-mode blockquote {
    border-left-color: var(--primary-color-dark);
    background-color: var(--code-background-dark);
}

/* ===========================
   TOP UTILITY NAVBAR
   =========================== */
.top-utility-navbar {
    background-color: var(--navbar-bg-light);
    padding: 0 20px;
    border-bottom: 1px solid var(--border-color-light);
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 1000;
    height: 60px;
    display: flex;
    align-items: center;
    transition: background-color 0.3s, border-bottom-color 0.3s, transform 0.3s ease-in-out;
}

.top-utility-navbar.navbar-hidden {
    transform: translateY(-100%);
}

.top-utility-navbar-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
}

.top-utility-navbar .navbar-brand {
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    font-size: 1.5em;
    color: var(--text-color-light);
    text-decoration: none;
}

.top-utility-navbar .navbar-links-right {
    display: flex;
    align-items: center;
    padding-right: 30px;
}

.top-utility-navbar .navbar-links-right a,
.top-utility-navbar .navbar-links-right #view-paper-button {
    margin-left: 20px;
    text-decoration: none;
    color: var(--text-muted-light);
    font-weight: 500;
    font-size: 1em;
    transition: color 0.3s ease, background-color 0.3s ease;
    background-color: transparent;
    border: none;
    padding: 0;
    cursor: pointer;
}

.top-utility-navbar .navbar-links-right a:hover,
.top-utility-navbar .navbar-links-right #view-paper-button:hover {
    color: var(--primary-color-light);
    background-color: var(--code-background-light);
    border-radius: 4px;
    padding: 5px 8px;
    margin-left: calc(20px - 8px);
    margin-right: -8px;
}

body.dark-mode .top-utility-navbar .navbar-links-right a,
body.dark-mode .top-utility-navbar .navbar-links-right #view-paper-button {
    color: var(--text-muted-dark);
}

body.dark-mode .top-utility-navbar .navbar-links-right a:hover,
body.dark-mode .top-utility-navbar .navbar-links-right #view-paper-button:hover {
    color: var(--primary-color-dark);
    background-color: var(--code-background-dark);
}

#theme-toggle-button {
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
    margin-left: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

#theme-toggle-button svg {
    width: 20px;
    height: 20px;
    stroke: var(--text-muted-light);
    transition: stroke 0.3s;
}

#theme-toggle-button:hover svg {
    stroke: var(--primary-color-light);
}

.hidden {
    display: none;
}

/* ===========================
   PAGE MAIN HEADER
   =========================== */
.page-main-header {
    margin-top: 0;
    min-height: 100vh;
    background: var(--header-bg-light);
    color: var(--text-color-light);
    padding-top: 70px;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    text-align: left;
    border-bottom: 1px solid var(--border-color-light);
    transition: background-color 0.3s, color 0.3s, border-bottom-color 0.3s;
    box-sizing: border-box;
}

.page-main-header .header-image-container {
    width: 100%;
    max-width: 1200px;
    margin-top: calc(2%);
    padding-left: 0;
    padding-right: 0;
    box-sizing: border-box;
    height: 50vh;
    border-radius: 8px;
    overflow: hidden;
}

.page-main-header .header-image-container img {
    display: block;
    width: calc(100% - 130px);
    margin-left: 80px;
    height: 100%;
    object-fit: cover;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    border-radius: 10px;
}

.page-main-header .header-text-content {
    width: 100%;
    max-width: 1200px;
    padding: 0px 50px 0px 80px;
    box-sizing: border-box;
}

.page-main-header .header-text-name {
    width: 100%;
    max-width: 1200px;
    padding: 0px 50px 0px 80px;
    box-sizing: border-box;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.author-info-block {
    flex-grow: 0;
}

.share-button-container {
    margin-left: 20px;
    position: relative;
}

#page-share-button {
    background-color: transparent;
    border: 1px solid var(--border-color-light);
    color: var(--text-muted-light);
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    font-family: 'Open Sans', sans-serif;
    font-size: 0.9em;
    font-weight: 500;
    transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, transform 0.1s ease;
}

#page-share-button svg {
    margin-right: 6px;
}

#page-share-button:hover {
    color: var(--primary-color-light);
    background-color: var(--code-background-light);
    border-color: var(--primary-color-light);
    transform: translateY(-1px);
}

.share-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background-color: var(--card-background-light);
    border: 1px solid var(--border-color-light);
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    z-index: 1001;
    width: max-content;
    min-width: 170px;
    padding: 6px 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(5px);
    transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
}

.share-dropdown:not(.hidden) {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.share-dropdown-item {
    display: flex;
    align-items: center;
    padding: 8px 15px;
    color: var(--text-color-light);
    text-decoration: none;
    font-size: 0.9em;
    font-family: 'Open Sans', sans-serif;
    background-color: transparent;
    border: none;
    width: 100%;
    text-align: left;
    cursor: pointer;
    transition: background-color 0.2s ease, color 0.2s ease;
    border-radius: 3px;
}

.share-dropdown-item svg {
    margin-right: 10px;
    fill: currentColor;
    stroke: currentColor;
}

.share-dropdown-item:hover {
    background-color: var(--code-background-light);
    color: var(--primary-color-light);
}

.copy-feedback {
    padding: 5px 15px;
    font-size: 0.8em;
    color: var(--accent-color-light);
    text-align: center;
}

.page-main-header .header-image-container,
.page-main-header .header-text-content,
.page-main-header .header-text-name {
    width: 100%;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    box-sizing: border-box;
}

.page-main-header .header-text-content,
.page-main-header .header-text-name {
    padding-left: 80px;
    padding-right: 50px;
}

.page-main-header h1 {
    margin: 10px 0 5px 0;
    font-size: 2.5em;
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    color: #0065a9;
    line-height: 1.25;
}

.page-main-header p {
    margin-top: 0;
    font-size: 1.2em;
    opacity: 0.85;
    color: var(--text-muted-light);
}

.page-main-header .header-text-name h3 {
    margin-top: 2px;
    margin-bottom: 2px;
    line-height: 1.3;
}

.page-main-header .header-text-name h6 {
    margin-bottom: 0px;
    line-height: 1.3;
}

.page-main-header .header-text-name p {
    line-height: 1.4;
}

/* ===========================
   MAIN CONTENT LAYOUT
   =========================== */
.page-content-wrapper {
    display: flex;
    max-width: 1400px;
    margin-left: auto;
    margin-right: auto;
    margin-top: 20px;
    padding: 0;
}

.sidebar {
    width: 350px;
    flex-shrink: 0;
    position: sticky;
    top: 60px;
    height: calc(100vh - 65px);
    overflow-y: auto;
    padding: 20px 15px;
    background-color: var(--sidebar-bg-light);
    border-right: 1px solid var(--border-color-light);
    transition: background-color 0.3s, border-right-color 0.3s, top 0.3s ease-in-out;
}

.sidebar h3 {
    margin-top: 0;
    color: var(--primary-color-light);
    font-size: 1.2em;
    font-family: 'Poppins', sans-serif;
    font-weight: 500;
    border-bottom: 2px solid var(--secondary-color-light);
    padding-bottom: 1px;
}

#toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

#toc-list>li {
    margin-bottom: 2px;
    position: relative;
}

#toc-list>li>a {
    color: var(--text-muted-light);
    text-decoration: none;
    display: block;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.9em;
    transition: color 0.2s ease, background-color 0.2s ease;
}

#toc-list>li>a:hover {
    color: var(--primary-color-light);
}

#toc-list>li>a.active {
    color: var(--primary-color-light);
    font-weight: 600;
}

/* Styling for sub-lists (H3 items) - Initially hidden */
#toc-list ul {
    list-style: none;
    padding-left: 15px;
    margin-top: 5px;
    margin-bottom: 5px;
    border-left: 1px solid var(--border-color-light);
    max-height: 0;
    /* Initially hidden */
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    /* Smooth transition */
}

body.dark-mode #toc-list ul {
    border-left-color: var(--border-color-dark);
}

#toc-list ul li {
    margin-bottom: 3px;
}

#toc-list ul li a {
    font-size: 0.8em;
    color: var(--text-muted-light);
    padding: 4px 8px;
    display: block;
    border-radius: 3px;
    text-decoration: none;
    transition: color 0.2s ease;
}

#toc-list ul li a:hover {
    color: var(--secondary-color-light);
}

#toc-list ul li a.active {
    color: var(--secondary-color-light);
    font-weight: 500;
}

body.dark-mode #toc-list ul li a {
    color: #b0b0b0;
}

body.dark-mode #toc-list ul li a:hover {
    color: var(--secondary-color-dark);
}

body.dark-mode #toc-list ul li a.active {
    color: var(--secondary-color-dark);
    font-weight: 500;
}

.content-area {
    flex-grow: 1;
    padding: 0 120px 20px 50px;
    min-width: 0;
}

/* ===========================
   CONTENT SECTIONS
   =========================== */
section {
    padding: 20px 0;
    margin-bottom: 40px;
    transition: background-color 0.3s, border-color 0.3s;
}

section[id],
h3[id] {
    scroll-margin-top: 80px;
}

h2 {
    color: var(--primary-color-light);
    border-bottom: 2px solid var(--secondary-color-light);
    padding-bottom: 10px;
    margin-top: 0;
    margin-bottom: 20px;
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    font-size: 1.8em;
}

h3 {
    color: var(--secondary-color-light);
    margin-top: 25px;
    margin-bottom: 12px;
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    font-size: 1.4em;
}

h4 {
    color: var(--primary-color-light);
    margin-top: 20px;
    margin-bottom: 8px;
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    font-size: 1.15em;
}

h6 {
    color: var(--text-muted-light);
    font-size: 0.9em;
    font-weight: 400;
    margin: 5px 0;
}

/* ===========================
   FEATURE GRID
   =========================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.feature-item {
    background-color: var(--background-color-light);
    padding: 15px;
    border-radius: 6px;
    border: 1px solid var(--border-color-light);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    display: flex;
    flex-direction: column;
}

.feature-item p {
    margin-bottom: 5px;
    flex-grow: 1;
}

.feature-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.12);
}

.feature-item h4 {
    margin-top: 0;
    color: var(--primary-color-light);
    font-size: 1.2em;
    margin-bottom: 10px;
}

/* ===========================
   TECH STACK LIST
   =========================== */
.tech-stack-list {
    list-style: none;
    padding: 0;
}

.tech-stack-list li {
    margin-bottom: 10px;
    padding: 5px 0;
}

.tech-stack-list li strong {
    color: var(--primary-color-light);
    margin-right: 8px;
    font-size: 1.05em;
}

.tech-stack-list li ul {
    padding-left: 15px;
    margin-top: 8px;
}

.tech-stack-list li ul li {
    margin-bottom: 4px;
    background-color: transparent;
    border: none;
    padding: 2px 0;
}

body.dark-mode .tech-stack-list li strong {
    color: var(--primary-color-dark);
}

/* ===========================
   CODE BLOCKS
   =========================== */
code {
    background-color: var(--code-background-light);
    padding: 0.2em 0.4em;
    margin: 0;
    font-size: 0.9em;
    border-radius: 3px;
    font-family: Consolas, Monaco, 'Andale Mono', 'Ubuntu Mono', monospace;
    color: var(--text-color-light);
}

pre {
    background-color: var(--code-background-light);
    padding: 15px;
    border-radius: 6px;
    overflow-x: auto;
    margin: 20px 0;
    line-height: 1.5;
    font-size: 0.9em;
    border: 1px solid var(--border-color-light);
}

pre code {
    background-color: transparent;
    padding: 0;
    border-radius: 0;
    font-size: 1em;
    border: none;
}

/* ===========================
   LISTS
   =========================== */
ul,
ol {
    padding-left: 20px;
    margin-bottom: 15px;
}

#toc-list ul,
#toc-list ol {
    padding-left: 15px;
}

ul li,
ol li {
    margin-bottom: 8px;
}

#toc-list li,
#toc-list ul li {
    margin-bottom: 3px;
}

/* ===========================
   LINKS
   =========================== */
a {
    color: var(--link-color-light);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--link-hover-light);
    text-decoration: underline;
}

/* ===========================
   BLOCKQUOTES
   =========================== */
blockquote {
    border-left: 4px solid var(--primary-color-light);
    padding-left: 20px;
    margin: 20px 0;
    font-style: italic;
    background-color: var(--code-background-light);
    padding: 15px 20px;
    border-radius: 4px;
}

blockquote p {
    margin: 0;
}

/* ===========================
   ACCORDION STYLES
   =========================== */
.accordion-container {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.accordion-item {
    transition: background-color 0.3s, border-color 0.3s;
    margin-bottom: 15px;
}

.accordion-header {
    color: var(--text-color-light);
    cursor: pointer;
    padding: 10px 0;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 1.3em;
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    background-color: var(--background-color-light);
    transition: color 0.2s ease;
}

.accordion-header:hover {
    color: var(--primary-color-light);
}

.accordion-icon {
    font-size: 1.4em;
    font-weight: bold;
    transition: transform 0.3s ease;
}

.accordion-header.active .accordion-icon {
    transform: rotate(45deg);
}

.accordion-content {
    padding: 0 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out, padding 0.4s ease-out;
}

.accordion-content.active {
    padding: 15px 0;
}

.accordion-content p {
    margin-bottom: 10px;
    line-height: 1.7;
}

.accordion-content p:last-child {
    margin-bottom: 0;
}

.accordion-content ul {
    margin-top: 10px;
}

/* ===========================
   FOOTER
   =========================== */
footer {
    text-align: center;
    padding: 25px 0;
    margin-top: 30px;
    color: var(--text-muted-light);
    font-size: 0.9em;
    border-top: 1px solid var(--border-color-light);
    transition: color 0.3s, border-top-color 0.3s;
}

/* ===========================
   RESPONSIVE DESIGN
   =========================== */
@media (max-width: 1024px) {
    .page-content-wrapper {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        position: static;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border-color-light);
    }

    .content-area {
        padding: 0 20px 20px 20px;
    }

    .page-main-header .header-image-container img {
        width: calc(100% - 40px);
        margin-left: 20px;
    }

    .page-main-header .header-text-content,
    .page-main-header .header-text-name {
        padding-left: 20px;
        padding-right: 20px;
    }
}

@media (max-width: 768px) {
    .page-main-header h1 {
        font-size: 2em;
    }

    .page-main-header p {
        font-size: 1em;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .top-utility-navbar .navbar-links-right {
        padding-right: 10px;
    }

    .top-utility-navbar .navbar-links-right a,
    .top-utility-navbar .navbar-links-right #view-paper-button {
        margin-left: 10px;
        font-size: 0.9em;
    }

    .page-main-header .header-text-name {
        flex-direction: column;
        align-items: flex-start;
    }

    .share-button-container {
        margin-left: 0;
        margin-top: 15px;
    }
}