/*
 * Daniel R. Jiang Webpage Design/Template
 *
 * ============================================================================
 * To adapt this site for your own use, modify these key variables:
 *
 * COLORS:
 *   --highlight-color-r/g/b: RGB values for the green highlighter effect
 *   --color-black through --color-white: Grayscale palette
 *
 * TYPOGRAPHY:
 *   --font-display: Serif font for headings (default: Cormorant Garamond)
 *   --font-body: Sans-serif font for body text (default: Inter)
 *
 * SIZING:
 *   --max-width: Maximum content width (default: 750px)
 *   --photo-size: Profile photo size
 *   --icon-size: Publication icon size
 *
 * RESPONSIVE:
 *   All font sizes use clamp(min, preferred, max) for fluid scaling.
 *   The middle value (e.g., 2.1vw) controls how fast it scales.
 * ============================================================================
 *
 * Table of Contents:
 * 1. CSS Variables
 * 2. Reset & Base
 * 3. Typography
 * 4. Layout Containers
 * 5. Bio Card
 * 6. Section Headers & Collapsible
 * 7. Tag System (filters + publication tags)
 * 8. Content Rows (shared: publications, courses, projects)
 * 9. Publications
 * 10. Teaching
 * 11. Footer & Utilities
 * 12. Responsive
 * 13. Print
 */

/* ==========================================================================
   1. CSS Variables
   ========================================================================== */

:root {
    /* Highlight Color (RGB components for use in rgba()) */
    --highlight-color-r: 60;
    --highlight-color-g: 140;
    --highlight-color-b: 80;
    --highlight-gradient: linear-gradient(
        98deg,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0) 0%,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0.20) 1.5%,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0.10) 8%,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0.13) 92%,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0.18) 98.5%,
        rgba(var(--highlight-color-r), var(--highlight-color-g), var(--highlight-color-b), 0) 100%
    );

    /* Grayscale Palette */
    --color-black: #121212;
    --color-ink: #1a1a1a;
    --color-gray-dark: #333333;
    --color-gray: #666666;
    --color-gray-light: #999999;
    --color-gray-pale: #e8e8e8;
    --color-white: #ffffff;

    /* Typography */
    --font-display: 'Cormorant Garamond', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --bio-font-size: clamp(0.55rem, 2.05vw, 0.9rem);
    --bio-contact-font-size: clamp(0.65rem, 2.05vw, 0.9rem);
    --bio-line-height: 1.7;
    --bio-line-height-compact: 1.6;
    --bio-line-height-compact-2: 1.48;
    --publication-title-font-size: clamp(0.45rem, 2.1vw, 0.85rem);
    --publication-authors-font-size: clamp(0.4rem, 2.0vw, 0.8rem);
    --publication-venue-font-size: clamp(0.4rem, 2.0vw, 0.8rem);
    --publication-description-font-size: clamp(0.35rem, 1.8vw, 0.72rem);
    --publication-links-font-size: clamp(0.4rem, 2.0vw, 0.8rem);
    --tag-pill-font-size: clamp(0.25rem, 1.3vw, 0.6rem);
    --tag-pill-padding-v: clamp(1px, 0.3vw, 2px);
    --tag-pill-padding-h: clamp(2px, 0.8vw, 8px);
    --tag-pill-bg: #f3f3f3;
    --tag-pill-gap: clamp(2px, 0.5vw, 3px);
    --icon-tags-margin-top: clamp(3px, 1vw, 6px);
    --tag-filter-font-size: clamp(0.6rem, 1.8vw, 0.75rem);

    /* Marginalia (News Section) */
    --marginalia-label-font-size: clamp(0.65rem, 2.2vw, 1.0rem);
    --marginalia-item-font-size: var(--publication-authors-font-size);
    --marginalia-gap: clamp(3px, 2vw, 10px);
    --marginalia-vspace: calc(var(--publication-vspace) * 2.5);

    /* Layout */
    --max-width: 750px;
    --photo-size: clamp(55px, 18vw, 117px);
    --icon-size: clamp(25px, 10vw, 80px);

    /* Spacing */
    --space-sm: 6px;
    --space-md: 12px;
    --space-lg: 18px;
    --space-xl: 28px;
    --space-2xl: 40px;
    --publication-vspace: clamp(2px, 0.6vw, 5px);
    --link-item-hspace: clamp(2px, 0.6vw, 5px);

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
}

/* ==========================================================================
   2. Reset & Base
   ========================================================================== */

*,
*::before,
*::after {
    box-sizing: border-box;
    max-width: 100%;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    visibility: hidden;
}

html.fonts-loaded {
    visibility: visible;
}

/* Font loading fallback */
@supports (animation: none) {
    html {
        animation: fonts-fallback 0s 0.3s forwards;
    }
    @keyframes fonts-fallback {
        to { visibility: visible; }
    }
    html.fonts-loaded {
        animation: none;
    }
}

body {
    margin: 0;
    padding: var(--space-2xl) var(--space-lg);
    background-color: var(--color-white);
    color: var(--color-ink);
    font-family: var(--font-body);
    font-size: 0.9rem;
    line-height: 1.6;
    font-weight: 450;
    overflow-x: hidden;
    overflow-wrap: break-word;
}

/* ==========================================================================
   3. Typography
   ========================================================================== */

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 500;
    color: var(--color-black);
    margin: 0;
    padding: 0;
    line-height: 1.2;
}

p {
    margin: 0 0 var(--space-sm) 0;
    padding: 0;
}

a {
    color: var(--color-black);
    text-decoration: none;
    transition: color var(--transition-fast);
}

/* ==========================================================================
   4. Layout Containers
   ========================================================================== */

.container-fluid {
    padding: 0;
    margin: 0;
    width: 100%;
}

.content-section {
    max-width: var(--max-width);
    margin: 0 auto var(--space-lg) auto;
    padding: var(--space-lg) 0;
    background: var(--color-white);
}

.content-section a {
    color: var(--color-ink);
}

.content-section a:hover {
    color: var(--color-black);
}

/* ==========================================================================
   5. Bio Card
   ========================================================================== */

.bio-card {
    max-width: var(--max-width);
    margin: 0 auto var(--space-xl) auto;
    padding: var(--space-lg) 0 0 0;
    background: var(--color-white);
}

.bio-name {
    font-size: clamp(1.8rem, 6.4vw, 3.2rem);
    line-height: 1.2;
    color: var(--color-black);
    font-weight: 600;
    font-family: var(--font-display);
    margin-bottom: var(--space-lg);
    letter-spacing: -0.02em;
}

/* Bio Grid */
.bio-grid {
    display: grid;
    grid-template-columns: var(--photo-size) 1fr;
    gap: clamp(var(--space-md), 4vw, var(--space-xl));
}

/* Photo & Social */
.bio-social,
.bio-right {
    display: grid;
    grid-template-rows: 1fr auto;
    align-content: space-between;
}

.bio-social {
    text-align: center;
    padding-top: 2px;
}

.bio-social img {
    width: var(--photo-size);
    height: auto;
    border-radius: 4px;
    margin: 0 0 var(--space-sm) 0;
    display: block;
}

.bio-social .social-links {
    display: flex;
    justify-content: center;
    gap: clamp(5px, 1.8vw, 10px);
    margin-top: auto;
    padding-top: var(--space-md);
}

.bio-social .social-links a {
    color: var(--color-gray);
    font-size: clamp(0.5rem, 1.5vw, 0.75rem);
    width: clamp(16px, 3.3vw, 26px);
    height: clamp(16px, 3.3vw, 26px);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--color-gray-pale);
    border-radius: 50%;
    transition: all var(--transition-fast);
}

.bio-social .social-links a:hover {
    color: var(--color-black);
    border-color: var(--color-black);
}

.bio-card .bio-right p {
    font-size: var(--bio-font-size);
    line-height: var(--bio-line-height);
    font-weight: 500;
    color: var(--color-ink);
    margin: 0;
    text-wrap: auto;
}

.bio-card .bio-right p a:not(.publication-links a):not(.contact-info a) {
    color: inherit;
    text-decoration: underline;
    text-decoration-style: dashed;
    text-decoration-color: #c8c8c8;
    text-underline-offset: 2px;
    transition: text-decoration-color var(--transition-fast);
}

.bio-card .bio-right p a:not(.publication-links a):not(.contact-info a):hover {
    text-decoration-color: #a0a0a0;
}

/* Contact Info */
.contact-info {
    margin-top: auto;
    padding-top: var(--space-md);
    font-size: var(--bio-contact-font-size);
    font-weight: 500;
}

.contact-info i {
    color: var(--color-gray);
    margin-right: 4px;
}

.contact-info i + i,
.contact-info a + i {
    margin-left: 12px;
}

.contact-info a {
    color: var(--color-black);
    border-bottom: none;
}

.contact-info a:hover {
    color: var(--color-gray-dark);
}

/* ==========================================================================
   5a. Marginalia News
   ========================================================================== */

.marginalia-section {
    max-width: var(--max-width);
    margin: clamp(28px, 8vw, 56px) auto clamp(21px, 6vw, 42px) auto;
}

.marginalia-container {
    display: flex;
    gap: var(--marginalia-gap);
    align-items: flex-start;
}

.marginalia-label {
    font-family: var(--font-display);
    font-size: var(--marginalia-label-font-size);
    font-weight: 550;
    font-style: italic;
    color: var(--color-gray);
    letter-spacing: 0.02em;
    white-space: nowrap;
    padding-top: 0.15em;
}

.marginalia-items {
    display: flex;
    flex-direction: column;
    gap: var(--marginalia-vspace);
    border-left: 1px solid var(--color-gray-pale);
    padding-left: var(--marginalia-gap);
}

.marginalia-item {
    display: flex;
    align-items: baseline;
    gap: calc(var(--marginalia-gap) * 0.5);
    font-size: var(--marginalia-item-font-size);
    line-height: 1.4;
}

.marginalia-date {
    font-family: var(--font-display);
    font-style: italic;
    color: var(--color-gray);
    white-space: nowrap;
    min-width: 3.0em;
}

.marginalia-text {
    color: var(--color-gray-dark);
    font-style: italic;
}

.marginalia-text a {
    color: var(--color-gray-dark);
    text-decoration: none;
    border-bottom: 1px dashed var(--color-gray-pale);
    transition: border-color var(--transition-fast);
}

.marginalia-text a:hover {
    border-color: var(--color-gray);
}

/* Subtle highlight for news items (uses same color as .highlight-organic) */
.marginalia-highlight {
    background: var(--highlight-gradient);
    padding: 0.05em 0.2em;
    margin: 0 -0.1em;
    border-radius: 0.4em 0.2em;
}

/* Expandable News */
.marginalia-items-wrapper {
    position: relative;
    flex: 1;
}

.marginalia-items-wrapper .marginalia-items {
    overflow: hidden;
}

.marginalia-items-wrapper:not(.expanded) .marginalia-items > .marginalia-item:nth-child(3) {
    opacity: 0.9;
}

.marginalia-items-wrapper:not(.expanded) .marginalia-items > .marginalia-item:nth-child(4) {
    opacity: 0.8;
}

.marginalia-items-wrapper:not(.expanded) .marginalia-items > .marginalia-item:nth-child(5) {
    opacity: 0.6;
}

.marginalia-items-wrapper:not(.expanded) .marginalia-items > .marginalia-item:nth-child(n+6) {
    display: none;
}

.marginalia-items-wrapper.expanded .marginalia-items > .marginalia-item:nth-child(n+6) {
    display: flex;
}

.marginalia-fade {
    display: none;
}

.marginalia-toggle {
    display: inline;
    background: none;
    border: none;
    padding: 0;
    font-family: var(--font-display);
    font-size: var(--marginalia-item-font-size);
    font-style: italic;
    color: var(--color-gray);
    cursor: pointer;
    margin-top: calc(var(--publication-vspace) * 2);
}

.marginalia-toggle:hover {
    color: var(--color-gray-dark);
}

/* Highlighter */
.highlight-organic {
    background: var(--highlight-gradient);
    padding: 0.05em 0.25em;
    margin: 0 -0.15em;
    border-radius: 0.6em 0.25em;
    -webkit-box-decoration-break: clone;
    box-decoration-break: clone;
}

/* ==========================================================================
   6. Section Headers
   ========================================================================== */

.section-header-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid var(--color-black);
    margin-bottom: var(--space-lg);
}

.section-header {
    font-size: clamp(1.1rem, 3.5vw, 1.7rem);
    font-weight: 650;
    letter-spacing: -0.01em;
    margin: 0;
}

/* ==========================================================================
   7. Tag System
   ========================================================================== */

/* Base Tag Style (used in .icon-tags under publication thumbnails) */
.tag {
    display: inline-block;
    font-size: var(--tag-pill-font-size);
    font-weight: 500;
    padding: var(--tag-pill-padding-v) var(--tag-pill-padding-h);
    border-radius: 12px;
    background-color: var(--tag-pill-bg);
    color: var(--color-gray);
    opacity: 0.8;
}

/* Filter Dropdown */
.filter-dropdown {
    position: relative;
}

.filter-toggle {
    font-size: clamp(0.5rem, 1.6vw, 0.7rem);
    font-weight: 500;
    color: var(--color-gray-light);
    cursor: pointer;
    user-select: none;
}

.filter-toggle:hover {
    color: var(--color-gray);
}

.filter-toggle i {
    font-size: 0.8em;
    margin-right: 3px;
}

.filter-dropdown.open .filter-toggle {
    color: var(--color-gray-dark);
}

/* Filter Tags Container (Dropdown) */
.tag-filters {
    display: none;
    flex-direction: column;
    gap: 0;
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: var(--space-sm);
    padding: 4px;
    background: var(--color-white);
    border: 1px solid var(--color-gray-pale);
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    z-index: 100;
    min-width: 60px;
}

.filter-dropdown.open .tag-filters {
    display: flex;
}

/* Filter Tag Buttons */
.tag-filter {
    font-size: var(--tag-filter-font-size);
    font-weight: 500;
    padding: 4px 10px;
    border-radius: 4px;
    background-color: transparent;
    border: none;
    color: var(--color-gray);
    cursor: pointer;
    user-select: none;
    white-space: nowrap;
    text-align: left;
}

.tag-filter:hover {
    background-color: var(--color-gray-pale);
    color: var(--color-gray-dark);
}

.tag-filter.active {
    background-color: var(--color-black);
    color: var(--color-white);
}

/* Publication Icon Tags */
.icon-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--tag-pill-gap);
    margin-top: var(--icon-tags-margin-top);
}

/* ==========================================================================
   8. Content Rows (Shared Styles)
   ========================================================================== */

/* Base row layout for publications, courses, and projects */
.publication-row,
.course-row {
    display: grid;
    grid-template-columns: var(--icon-size) 1fr;
    gap: clamp(var(--space-md), 3vw, var(--space-lg));
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-lg);
    padding-left: var(--space-md);
    border-bottom: 1px solid var(--color-gray-pale);
    align-items: start;
}

.publication-row:last-child,
.course-row:last-child {
    border-bottom: none;
    margin-bottom: 0;
}

.row-icon,
.row-content {
    width: auto;
    padding: 0;
}

.row-icon a {
    display: block;
}

/* ==========================================================================
   9. Publications
   ========================================================================== */

/* Publication row filter animation */
.publication-row {
    transition: opacity var(--transition-base),
                transform var(--transition-base),
                max-height 0.4s ease,
                margin-bottom var(--transition-base),
                padding-bottom var(--transition-base);
    overflow: hidden;
}

.publication-row.filtered-out {
    opacity: 0;
    transform: translateY(-10px);
    max-height: 0;
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
    pointer-events: none;
}

.publication-row.last-visible {
    border-bottom: none;
}

/* Publication Icon/Thumbnail */
.publication-icon {
    width: 100%;
    height: auto;
    border-radius: 3px;
    opacity: 0.55;
    filter: grayscale(80%);
    transition: all 0.25s ease;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.15);
}

.publication-row:hover .publication-icon {
    opacity: 1;
    filter: grayscale(50%);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.12);
}

/* Publication Typography */
.publication-title,
.course-row h5 {
    font-family: var(--font-body);
    font-size: var(--publication-title-font-size);
    line-height: 1.4;
    color: var(--color-black);
    margin-bottom: var(--publication-vspace);
    text-wrap: auto;
}

.publication-authors,
.teaching-position {
    font-size: var(--publication-authors-font-size);
    line-height: 1.4;
    color: var(--color-gray-dark);
    margin-bottom: var(--publication-vspace);
    padding-left: var(--space-md);
    text-wrap: auto;
}

.teaching-position {
    font-style: italic;
    color: var(--color-gray);
}

.author-self {
    font-weight: 650;
    color: var(--color-black);
}

.publication-journal {
    font-size: var(--publication-venue-font-size);
    line-height: 1.4;
    color: var(--color-black);
    margin-bottom: var(--publication-vspace);
    padding-left: var(--space-md);
    text-wrap: auto;
}

.publication-journal a {
    color: var(--color-black);
    font-weight: 650;
}

.journal-submitted,
.journal-submitted a {
    font-weight: 400;
    color: var(--color-gray-dark);
}

/* Publication Description */
.publication-description-wrapper {
    padding-left: var(--space-md);
    margin-bottom: var(--publication-vspace);
    font-size: var(--publication-description-font-size);
    line-height: 1.4;
    color: var(--color-gray);
    text-wrap: auto;
}

.publication-description-text {
    display: block;
}

.publication-measure {
    position: absolute;
    visibility: hidden;
    height: auto;
    white-space: normal;
    pointer-events: none;
}

.abstract-toggle {
    color: var(--color-gray-light);
    cursor: pointer;
    user-select: none;
    transition: color var(--transition-fast);
}

.abstract-toggle:hover {
    color: var(--color-gray-dark);
}

/* Publication Links */
.publication-links {
    font-size: var(--publication-links-font-size);
    color: var(--color-gray-dark);
    padding-left: var(--space-md);
    text-wrap: auto;
}

.publication-links .link-item {
    display: inline-block;
    white-space: nowrap;
    margin-right: var(--link-item-hspace);
}

.publication-links .link-item:last-child {
    margin-right: 0;
}

.publication-links i {
    display: inline-block;
    color: var(--color-gray-dark);
    margin-right: 4px;
}

.publication-links a {
    color: var(--color-gray-dark);
}

.publication-links a:hover {
    color: var(--color-black);
}

/* Featured Links (uses highlight-organic for background) */
.featured-wrap {
    display: inline-block;
    margin-right: 0.3em;
}

.publication-links .featured-wrap a {
    color: var(--color-gray-dark);
    font-weight: 550;
    letter-spacing: -0.01em;
}

.publication-links .featured-wrap a:hover {
    color: var(--color-black);
}

.publication-links .featured-wrap i {
    color: var(--color-gray-dark);
    margin-right: 4px;
}

/* ==========================================================================
   10. Teaching
   ========================================================================== */

.course-row h5 a {
    border: none;
}

/* ==========================================================================
   11. Footer & Utilities
   ========================================================================== */

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 40px;
    height: 40px;
    background: var(--color-white);
    border: 1px solid var(--color-gray-pale);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 1000;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--color-black);
    border-color: var(--color-black);
}

.back-to-top i {
    font-size: 0.9rem;
    color: var(--color-gray);
    transition: color var(--transition-base);
}

.back-to-top:hover i {
    color: var(--color-white);
}

.template-credit {
    text-align: center;
    margin: calc(var(--space-2xl) * 1.1) 0 var(--space-xl);
    font-family: var(--font-body);
    font-size: var(--publication-description-font-size);
    font-style: normal;
    color: var(--color-gray);
    letter-spacing: 0;
}

.template-credit a {
    color: var(--color-gray-dark);
    border-bottom: 1px solid var(--color-gray-pale);
}

.template-credit a:hover {
    color: var(--color-black);
    border-color: var(--color-gray);
}

/* ==========================================================================
   12. Responsive
   ========================================================================== */

/* Touch devices: always show interactive elements */
@media (hover: none) {
    .publication-icon {
        opacity: 0.85;
        filter: grayscale(50%);
    }
}

/* Bio text line-height adjustment */
@media (max-width: 650px) {
    .bio-card .bio-right p {
        line-height: var(--bio-line-height-compact);
        text-wrap: auto;
    }
}

@media (max-width: 400px) {
    .bio-card .bio-right p {
        line-height: var(--bio-line-height-compact-2);
    }
}

/* Small screens */
@media (max-width: 576px) {
    body {
        padding: var(--space-lg) var(--space-md);
    }

    .bio-card,
    .content-section {
        margin-left: 0;
        margin-right: 0;
    }

    .section-header-row {
        padding-bottom: var(--space-sm);
    }

    .publication-row,
    .course-row {
        padding-left: 0;
        margin-bottom: var(--space-md);
        padding-bottom: var(--space-md);
    }

    .publication-authors,
    .teaching-position,
    .publication-journal,
    .publication-description-wrapper,
    .publication-links {
        padding-left: 8px;
    }
}

/* ==========================================================================
   13. Print
   ========================================================================== */

@media print {
    body {
        background: white;
        color: black;
    }

    .bio-social a > i {
        display: none;
    }

    a {
        text-decoration: underline;
    }

    .back-to-top {
        display: none !important;
    }
}