/* ── Reset & Base ──────────────────────────────────────── */
* { box-sizing: border-box; }

html {
    color-scheme: light dark;
    scrollbar-gutter: stable;
    scroll-behavior: smooth;
}

/* ── CSS Variables ─────────────────────────────────────── */
:root {
    --color-global-bg:   oklch(98.48% 0 0);
    --color-global-text: oklch(26.99% 0.0096 235.05);
    --color-link:        oklch(55.44% 0.0431 185.69);
    --color-accent:      #af67ff;
    --color-accent-2:    oklch(18.15% 0 0);
    --color-quote:       #af67ff;
    --color-border:      #e5e7eb;
    --color-card-bg:     rgba(255,255,255,0.8);
    --color-shadow:      rgba(0,0,0,0.1);
}

[data-theme="dark"] {
    --color-global-bg:   oklch(23.64% 0.0045 248);
    --color-global-text: oklch(83.54% 0 264);
    --color-link:        oklch(70.44% 0.1133 349);
    --color-accent:      #5ff26b;
    --color-accent-2:    oklch(94.66% 0 0);
    --color-quote:       oklch(94.8% 0.106 136.49);
    --color-border:      #374151;
    --color-card-bg:     rgba(31,41,55,0.8);
    --color-shadow:      rgba(0,0,0,0.3);
}

/* ── Body ──────────────────────────────────────────────── */
body {
    font-family: 'JetBrains Mono', 'Courier New', monospace;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    background-color: var(--color-global-bg);
    color: var(--color-global-text);
    padding-top: 8rem;
}

@media (max-width: 640px) {
    body { padding-top: 5rem; }
}

/* ── Utilities ─────────────────────────────────────────── */
.bg-global-bg    { background-color: var(--color-global-bg); }
.text-global-text{ color: var(--color-global-text); }
.mx-auto  { margin-left: auto; margin-right: auto; }
.flex     { display: flex; }
.items-center { align-items: center; }
.max-w-3xl{ max-width: 72rem; }
.px-4     { padding-left: 1rem;  padding-right: 1rem; }
.px-8     { padding-left: 2rem;  padding-right: 2rem; }
.py-8     { padding-top: 2rem;   padding-bottom: 2rem; }
.mb-16    { margin-bottom: 4rem; }
.text-xl  { font-size: 1.25rem; }
.text-sm  { font-size: 0.875rem; }
.font-bold{ font-weight: 700; }
.antialiased { -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
.scroll-smooth { scroll-behavior: smooth; }
.opacity-75 { opacity: 0.75; }
.text-center { text-align: center; }

@media (min-width: 640px) {
    .sm\:px-8   { padding-left: 2rem; padding-right: 2rem; }
    .sm\:text-2xl { font-size: 1.5rem; }
}

/* ── Header ────────────────────────────────────────────── */
#main-header {
    position: fixed;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    max-width: 72rem;
    width: 100%;
    background-color: color-mix(in srgb, var(--color-global-bg) 95%, transparent);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid color-mix(in srgb, var(--color-border) 50%, transparent);
    z-index: 100;
    padding: 0.75rem 1rem;
}

@media (min-width: 640px) {
    #main-header { padding: 0.75rem 2rem; }
}

.header-grid {
    display: grid;
    grid-template-columns: auto 1fr auto auto;
    grid-template-areas: "logo title nav controls";
    align-items: center;
    column-gap: 1rem;
}

.header-logo    { grid-area: logo;     text-decoration: none; }
.header-title   { grid-area: title;    min-width: 0; }
.header-nav     { grid-area: nav; }
.header-controls{ grid-area: controls; display: flex; align-items: center; gap: 0.5rem; }

/* Logo */
.logo-text {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 700;
    font-size: 1.125rem;
    color: var(--color-accent);
    padding: 0.2rem 0.5rem;
    border: 2px solid var(--color-accent);
    border-radius: 4px;
    display: inline-block;
    line-height: 1.4;
    transition: background-color 0.15s ease, color 0.15s ease;
}

.header-logo:hover .logo-text {
    background-color: var(--color-accent);
    color: var(--color-global-bg);
}

/* Desktop nav */
.mobile-nav-menu {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 0;
    margin: 0;
    padding: 0;
    list-style: none;
}

.mobile-nav-menu > a {
    padding: 0 0.875rem;
    border-left: 1px solid var(--color-accent);
    color: var(--color-accent);
    text-decoration: none;
    font-size: 0.9rem;
    white-space: nowrap;
    transition: opacity 0.15s ease;
}

.mobile-nav-menu > a:first-child { border-left: none; }

.mobile-nav-menu > a:hover,
.mobile-nav-menu > a.active {
    text-decoration: underline;
    text-underline-offset: 3px;
}

/* Mobile nav overlay */
@media (max-width: 640px) {
    .header-grid {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 0.75rem;
    }
    .header-title { flex: 1; }
    .header-nav   { display: none; }

    .mobile-nav-menu {
        position: fixed !important;
        inset: 0 !important;
        width: 100vw !important;
        height: 100vh !important;
        background-color: color-mix(in srgb, var(--color-global-bg) 97%, transparent) !important;
        backdrop-filter: blur(20px) !important;
        -webkit-backdrop-filter: blur(20px) !important;
        z-index: 150 !important;
        display: none !important;
        flex-direction: column !important;
        justify-content: center !important;
        align-items: center !important;
        gap: 1.5rem !important;
        padding: 2rem !important;
    }

    .mobile-nav-menu > a {
        font-size: 1.4rem !important;
        padding: 0.875rem 2rem !important;
        border-left: none !important;
        border: 1px solid var(--color-accent) !important;
        border-radius: 0.5rem !important;
        min-width: 200px !important;
        text-align: center !important;
        display: block !important;
        background-color: color-mix(in srgb, var(--color-accent) 8%, transparent) !important;
    }

    .mobile-nav-menu > a:hover {
        background-color: var(--color-accent) !important;
        color: var(--color-global-bg) !important;
        text-decoration: none !important;
        transform: translateY(-2px);
    }
}

.group.menu-open .mobile-nav-menu {
    display: flex !important;
    animation: fadeInScale 0.25s ease;
}

@keyframes fadeInScale {
    from { opacity: 0; transform: scale(0.97); }
    to   { opacity: 1; transform: scale(1); }
}

body.menu-open { overflow: hidden; }

/* Theme toggle */
#theme-toggle,
#toggle-navigation-menu {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    padding: 0.25rem;
    background-color: color-mix(in srgb, var(--color-accent-2) 12%, transparent);
    border: 1px solid color-mix(in srgb, var(--color-accent-2) 20%, transparent);
    border-radius: 0.375rem;
    cursor: pointer;
    -webkit-user-select: none;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
    transition: background-color 0.15s ease;
    flex-shrink: 0;
}

#theme-toggle:hover,
#toggle-navigation-menu:hover {
    background-color: color-mix(in srgb, var(--color-accent-2) 22%, transparent);
}

#theme-toggle svg,
#toggle-navigation-menu svg { width: 1rem; height: 1rem; }

#toggle-navigation-menu { display: none; z-index: 200; position: relative; }

@media (max-width: 640px) {
    #toggle-navigation-menu { display: flex; min-width: 44px; min-height: 44px; }
    #theme-toggle           { min-width: 44px; min-height: 44px; }
}

#toggle-navigation-menu[aria-expanded="false"] .menu-close-icon { display: none; }
#toggle-navigation-menu[aria-expanded="true"]  .menu-open-icon  { display: none; }

/* Theme icon */
[data-theme="dark"]  .sun-icon  { display: block; }
[data-theme="dark"]  .moon-icon { display: none;  }
[data-theme="light"] .sun-icon  { display: none;  }
[data-theme="light"] .moon-icon { display: block; }
:root .sun-icon  { display: none; }
:root .moon-icon { display: block; }

/* ── Scroll anchor margin ──────────────────────────────── */
:target { scroll-margin-top: 7rem; }

@media (max-width: 640px) {
    :target { scroll-margin-top: 5rem; }
}

/* ── Prose / Typography ────────────────────────────────── */
.prose { color: var(--color-global-text); max-width: none; }

.prose p { margin-bottom: 1.25rem; }

.prose a {
    color: var(--color-link);
    text-decoration: underline;
    text-underline-offset: 2px;
}
.prose a:hover { text-decoration-thickness: 2px; }

.prose strong {
    color: var(--color-accent-2);
    font-weight: 600;
}

.cactus-link {
    color: var(--color-link);
    text-decoration: underline;
    text-underline-offset: 2px;
}
.cactus-link:hover { text-decoration-thickness: 2px; }

/* ── Section / Subsection Titles ──────────────────────── */
.section-title {
    color: var(--color-accent-2);
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 0 2rem 0;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid color-mix(in srgb, var(--color-accent) 40%, transparent);
}

.subsection-title {
    color: var(--color-accent-2);
    font-size: 1.1rem;
    font-weight: 600;
    margin: 2rem 0 0.75rem 0;
    opacity: 0.85;
}

/* ── About Section ─────────────────────────────────────── */
.about-header {
    display: flex;
    align-items: flex-start;
    gap: 1.75rem;
    margin-bottom: 1.75rem;
}

.about-avatar {
    width: 110px;
    height: 110px;
    border-radius: 9999px;
    object-fit: cover;
    flex-shrink: 0;
    border: 2px solid var(--color-border);
    box-shadow: 0 4px 14px color-mix(in srgb, var(--color-shadow) 60%, transparent);
}

.about-header-content {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    padding-top: 0.25rem;
}

.about-name {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-accent-2);
    margin: 0;
    line-height: 1.2;
}

.about-role {
    font-size: 0.95rem;
    margin: 0;
    opacity: 0.85;
}

.about-location {
    font-size: 0.85rem;
    margin: 0;
    opacity: 0.6;
}

/* Contact chips */
.contact-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-top: 0.6rem;
}

.contact-chip {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.35rem 0.8rem;
    border: 1px solid var(--color-accent);
    border-radius: 9999px;
    color: var(--color-accent);
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 500;
    transition: background-color 0.15s ease, color 0.15s ease;
    white-space: nowrap;
}

.contact-chip:hover {
    background-color: var(--color-accent);
    color: var(--color-global-bg);
}

.contact-chip svg {
    width: 0.95rem;
    height: 0.95rem;
    flex-shrink: 0;
}

@media (max-width: 640px) {
    .about-header {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 1.25rem;
    }
    .about-avatar { width: 90px; height: 90px; margin-top: 0.5rem; }
    .about-header-content { align-items: center; }
    .contact-chips { justify-content: center; }
}

/* ── Timeline ──────────────────────────────────────────── */
.timeline {
    position: relative;
    margin: 0.5rem 0 1.5rem 0;
    padding-left: 2.5rem;
    --dot-size: 0.8rem;
    --line-x: 1.1rem;
    --line-w: 2px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: var(--line-x);
    top: 0.35rem;
    bottom: 0.35rem;
    width: var(--line-w);
    background: color-mix(in srgb, var(--color-accent-2) 18%, transparent);
}

.timeline-item {
    position: relative;
    padding-bottom: 1.75rem;
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-dot {
    position: absolute;
    left: calc(var(--line-x) - 2.5rem + (var(--line-w) - var(--dot-size)) / 2);
    top: 0.35rem;
    width: var(--dot-size);
    height: var(--dot-size);
    border-radius: 9999px;
    background: var(--color-accent);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 22%, transparent);
}

.timeline-header {
    display: flex;
    align-items: baseline;
    flex-wrap: wrap;
    gap: 0.35rem;
    line-height: 1.4;
}

.timeline-org {
    font-weight: 700;
    font-size: 0.975rem;
    color: var(--color-accent-2);
}

.timeline-role {
    font-size: 0.9rem;
    opacity: 0.85;
}

.timeline-dates {
    margin-left: auto;
    font-size: 0.775rem;
    letter-spacing: 0.02em;
    opacity: 0.6;
    white-space: nowrap;
}

.timeline-meta {
    font-size: 0.825rem;
    margin-top: 0.2rem;
    opacity: 0.65;
}

.timeline-desc {
    margin-top: 0.5rem;
}

.timeline-desc p {
    margin: 0;
    font-size: 0.875rem;
    line-height: 1.55;
}

.timeline-desc ul {
    margin: 0;
    padding-left: 1.2rem;
    list-style: disc;
}

.timeline-desc ul li {
    font-size: 0.875rem;
    line-height: 1.55;
    margin-bottom: 0.3rem;
    color: color-mix(in srgb, var(--color-global-text) 90%, transparent);
}

.timeline-desc ul li:last-child { margin-bottom: 0; }

@media (max-width: 640px) {
    .timeline { padding-left: 2rem; --line-x: 0.9rem; }
    .timeline-dates { width: 100%; margin-left: 0; margin-top: 0.1rem; }
}

/* ── Publication & Project Cards ───────────────────────── */
.publication-card {
    display: flex;
    flex-direction: row;
    align-items: flex-start;
    gap: 1.25rem;
    background-color: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: 0.75rem;
    padding: 1.25rem;
    margin-bottom: 1.5rem;
    backdrop-filter: blur(8px);
    transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.publication-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 28px var(--color-shadow);
}

/* Featured publication gets a subtle accent border */
.pub-featured {
    border-color: color-mix(in srgb, var(--color-accent) 40%, var(--color-border));
}

.publication-image {
    flex-shrink: 0;
    width: 400px;
    border-radius: 0.4rem;
    overflow: hidden;
    background-color: transparent;
    align-self: flex-start;
}

.publication-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* Icon placeholder for projects without an image */
.pub-icon-bg {
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: color-mix(in srgb, var(--color-accent) 10%, transparent);
}

.pub-icon-bg svg {
    width: 48px;
    height: 48px;
    color: var(--color-accent);
    opacity: 0.7;
}

.publication-content {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    gap: 0;
}

.publication-content .publication-title {
    margin-bottom: 0.4rem;
}

.publication-content .publication-venue {
    margin-bottom: 0.4rem;
}

.publication-content .publication-authors {
    margin-bottom: 0.5rem;
}

.publication-content .publication-description {
    margin-bottom: 0.6rem;
    flex: 1;
}

.publication-content .publication-tags {
    margin-bottom: 0.6rem;
}

.publication-content .project-links {
    margin-top: auto;
    padding-top: 0.5rem;
    border-top: 1px solid color-mix(in srgb, var(--color-border) 60%, transparent);
}

@media (max-width: 600px) {
    .publication-card {
        flex-direction: column;
    }
    .publication-image {
        width: 100%;
        height: 200px;
    }
}

.publication-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-accent-2);
    margin: 0;
    line-height: 1.35;
}

.publication-venue {
    display: inline-block;
    font-size: 0.775rem;
    font-weight: 600;
    color: var(--color-accent);
    background-color: color-mix(in srgb, var(--color-accent) 10%, transparent);
    padding: 0.2rem 0.5rem;
    border-radius: 0.25rem;
    width: fit-content;
}

.publication-authors {
    font-size: 0.825rem;
    opacity: 0.7;
    margin: 0;
}

.publication-description {
    font-size: 0.875rem;
    line-height: 1.55;
    opacity: 0.88;
    margin: 0;
}

.publication-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.project-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.project-links a {
    font-size: 0.825rem;
}

/* ── Tags ──────────────────────────────────────────────── */
.tag {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    padding: 0.2rem 0.5rem;
    border-radius: 0.25rem;
    border: 1px solid;
    white-space: nowrap;
    transition: transform 0.15s ease;
}

.tag:hover { transform: translateY(-1px); }

.tag-safety        { background-color: color-mix(in srgb, #ef4444 12%, transparent); border-color: #ef4444; color: #ef4444; }
.tag-interpretability { background-color: color-mix(in srgb, #af67ff 12%, transparent); border-color: #af67ff; color: #af67ff; }
.tag-arxiv         { background-color: color-mix(in srgb, #10b981 12%, transparent); border-color: #10b981; color: #10b981; }
.tag-workshop      { background-color: color-mix(in srgb, #f59e0b 12%, transparent); border-color: #f59e0b; color: #f59e0b; }
.tag-conference    { background-color: color-mix(in srgb, #3b82f6 12%, transparent); border-color: #3b82f6; color: #3b82f6; }
.tag-bibtex        { background-color: color-mix(in srgb, #6b7280 12%, transparent); border-color: #6b7280; color: #6b7280; }

/* ── Skills Tags ───────────────────────────────────────── */
.skills-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.skills-tags .tag {
    font-size: 0.8rem;
    padding: 0.3rem 0.7rem;
}

/* ── Footer ────────────────────────────────────────────── */
.site-footer {
    padding: 2.5rem 0 2rem 0;
    border-top: 1px solid color-mix(in srgb, var(--color-border) 60%, transparent);
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    margin-bottom: 1rem;
}

.footer-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    height: 2.25rem;
    border-radius: 9999px;
    border: 1px solid color-mix(in srgb, var(--color-accent) 40%, transparent);
    color: var(--color-accent);
    transition: background-color 0.15s ease, color 0.15s ease, transform 0.15s ease;
}

.footer-icon svg { width: 1.1rem; height: 1.1rem; }

.footer-icon:hover {
    background-color: var(--color-accent);
    color: var(--color-global-bg);
    transform: translateY(-2px);
}

.footer-copy {
    font-size: 0.8rem;
    opacity: 0.55;
    margin: 0;
}

/* ── Accessibility ─────────────────────────────────────── */
a:focus, button:focus { outline: none; }
a:focus-visible, button:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
    border-radius: 2px;
}

/* ── Custom Scrollbar ──────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--color-global-bg); }
::-webkit-scrollbar-thumb { background: color-mix(in srgb, var(--color-accent) 60%, transparent); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--color-accent); }

/* ── Responsive Typography ─────────────────────────────── */
@media (max-width: 640px) {
    .section-title  { font-size: 1.25rem; }
    .subsection-title { font-size: 1rem; }
    .about-name     { font-size: 1.25rem; }
}