/* ==========================================================================
   Ashvin Swaminathan — Academic Website
   Warm, minimal design · Light scholarly aesthetic
   ========================================================================== */

:root {
  --color-primary:     #034694;
  --color-accent:      #a08036;
  --color-link:        #034694;
  --color-link-hover:  #0558B8;
  --color-self:        #D4983D;
  --color-self-blue:   #0084ff;
  --color-tag-bg:      #f0ece2;
  --color-tag-hover:   #e5dfd2;
  --color-body:        #525252;
  --color-secondary:   #777;
  --color-muted:       #bbb;
  --color-bg:          #fbfbfb;
  --color-surface:     #ffffff;
  --color-hero-bg:     #f5f3ee;
  --color-border:      #ddd;
  --color-border-light:#eee;

  --font-heading: "Roboto", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-body:    "Roboto", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono:    "JetBrains Mono", "Fira Code", monospace;

  --transition-fast: 0.18s ease;
  --transition-med:  0.3s ease;
}

/* --- Reset --------------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  font-size: 17px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-weight: 300;
  line-height: 1.72;
  color: var(--color-body);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }

a {
  color: var(--color-link);
  text-decoration: none;
  transition: color var(--transition-fast);
}
a:hover, a:focus-visible { color: var(--color-link-hover); }

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--color-body);
}

p + p { margin-top: 0.8em; }

/* --- Skip Link ----------------------------------------------------------- */

.skip-link {
  position: absolute; top: -100%; left: 1rem; z-index: 9999;
  padding: 0.5em 1em; background: var(--color-accent); color: #fff;
  font-weight: 600; border-radius: 0 0 6px 6px;
  transition: top var(--transition-fast);
}
.skip-link:focus { top: 0; color: #fff; }

/* ==========================================================================
   HEADER — minimal single row
   Name left, links right
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(251, 251, 251, 0.95);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 48px;
  border-bottom: 1px solid var(--color-border-light);
}

.main-nav {
  display: flex;
  align-items: center;
}

.nav-links {
  display: flex;
  gap: 0.25rem;
  list-style: none;
  align-items: center;
}

.nav-links a {
  color: #777;
  font-size: 0.82rem;
  font-weight: 400;
  letter-spacing: 0.01em;
  text-decoration: none;
  transition: color var(--transition-fast), background var(--transition-fast);
  padding: 0.3rem 0.65rem;
  border-radius: 4px;
}

.nav-links a:hover {
  color: #333;
  background: rgba(0,0,0,0.04);
}

.nav-links a.active {
  color: var(--color-accent);
  font-weight: 500;
}

/* Hide dark mode toggle and header-top — light only */
.theme-toggle { display: none; }
.header-top { display: none; }

/* Hamburger for mobile */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.4rem;
  width: 32px;
  height: 32px;
}

.menu-toggle span {
  display: block; width: 20px; height: 1.5px;
  background: var(--color-body); border-radius: 1px;
  transition: transform var(--transition-med), opacity var(--transition-fast);
  transform-origin: center;
}

.menu-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ==========================================================================
   HOMEPAGE
   ========================================================================== */

/* --- Hero: warm full-width split ----------------------------------------- */

.hero {
  background: var(--color-hero-bg);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 3rem;
  align-items: center;
  max-width: 1100px;
  margin: 0 auto;
  padding: 3.5rem 2rem 3rem;
  min-height: 440px;
}

.hero-text h1 {
  font-size: 2.8rem;
  font-weight: 700;
  margin-bottom: 0.2em;
  letter-spacing: -0.03em;
  line-height: 1.05;
  color: #333;
}

.hero-role {
  font-size: 1.05rem;
  color: var(--color-secondary);
  font-weight: 300;
  margin-bottom: 1.2em;
  line-height: 1.55;
}

.hero-role strong {
  color: var(--color-accent);
  font-weight: 600;
  font-size: 1.1rem;
}

/* Hero structured sections */
.hero-sections {
  max-width: 600px;
}

.hero-section {
  margin-bottom: 0.7rem;
}

.hero-section h3 {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  margin-bottom: 0.3rem;
}

.hero-section p {
  font-size: 0.92rem;
  font-weight: 300;
  line-height: 1.65;
}

.hero-section p + p { margin-top: 0.4em; }

.hero-section em {
  font-style: normal;
  color: #333;
  font-weight: 400;
  white-space: nowrap;
}

/* Don't let em override link color */
.hero-section a em,
.hero-section a {
  color: var(--color-link);
}
.hero-section a:hover em,
.hero-section a:hover {
  color: var(--color-link-hover);
}

/* Hero actions row — placed near top */
.hero-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 1.2rem 0;
  padding: 1rem 0;
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
}

.job-market {
  display: inline-block;
  padding: 0.35em 0.8em;
  background: var(--color-accent);
  color: #fff !important;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 4px;
  line-height: 1.4;
}

.btn {
  display: inline-block;
  padding: 0.35em 0.8em;
  background: var(--color-link);
  color: #fff;
  font-weight: 500;
  font-size: 0.8rem;
  border-radius: 4px;
  text-decoration: none;
  line-height: 1.4;
  transition: background var(--transition-fast);
}
.btn:hover { background: var(--color-link-hover); color: #fff; }

.social-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  color: var(--color-secondary);
  transition: color var(--transition-fast);
}
.social-link:hover { color: var(--color-body); }

.hero-image {
  display: flex;
  justify-content: center;
}

.hero-image img {
  width: 100%;
  max-width: 340px;
  border-radius: 12px;
  object-fit: cover;
  aspect-ratio: 4 / 5;
  box-shadow: 0 8px 32px rgba(0,0,0,0.08);
}

/* --- Recent Activity ----------------------------------------------------- */

.recent-activity {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2.2rem 2rem 1.5rem;
}

.recent-activity h2 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--color-accent);
  font-weight: 600;
}

.activity-feed {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.activity-item {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding: 0.45rem 0;
  font-size: 0.9rem;
  line-height: 1.5;
}

.activity-item + .activity-item {
  border-top: 1px solid var(--color-border-light);
}

.activity-type {
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.15em 0.45em;
  border-radius: 3px;
}

.activity-type.paper    { background: #E3EBF6; color: #034694; }
.activity-type.talk     { background: #E6F4E6; color: #1B6B1B; }
.activity-type.upcoming { background: #FFF3DB; color: #8B6914; }
.activity-type.award    { background: #FFF3DB; color: #8B6914; }
.activity-type.news     { background: #F0E6F6; color: #5B2D8E; }

.activity-text {
  flex: 1;
  font-weight: 300;
}

.activity-detail {
  color: var(--color-secondary);
  font-size: 0.84rem;
}

/* ==========================================================================
   CONTENT PAGES
   ========================================================================== */

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Page title */
main > .container > h1,
.page-title {
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: #333;
  margin: 2rem 0 0.2rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--color-border);
  display: inline-block;
}

/* --- Research Interests -------------------------------------------------- */

.research-interests {
  margin: 1.2rem 0 1.8rem;
}

.research-interests h2 {
  font-size: 1rem;
  color: var(--color-secondary);
  margin-bottom: 0.5rem;
  font-weight: 400;
  font-family: var(--font-body);
}

.interest-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  list-style: none;
  padding: 0;
}

.interest-tags li {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.25em 0.6em;
  background: var(--color-tag-bg);
  color: var(--color-accent);
  border-radius: 3px;
  font-weight: 500;
}

/* --- Papers -------------------------------------------------------------- */

.papers-section {
  margin-bottom: 2.2rem;
}

.papers-section h2 {
  font-size: 1.25rem;
  margin-bottom: 0.8rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-accent);
}

.paper-list {
  list-style: none;
  padding: 0;
}

.paper-item {
  padding: 0.85rem 0 0.85rem 0.9rem;
  border-left: 2px solid transparent;
  transition: border-color var(--transition-med);
}

.paper-item:hover {
  border-left-color: var(--color-accent);
}

.paper-item + .paper-item {
  border-top: 1px solid var(--color-border-light);
}

.paper-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.4;
  margin-bottom: 0.15em;
}

.paper-authors {
  font-size: 0.86rem;
  color: var(--color-secondary);
  margin-bottom: 0.1em;
  font-weight: 300;
}

.self-author {
  color: var(--color-self);
  font-weight: 600;
}

.paper-venue {
  font-size: 0.84rem;
  color: var(--color-secondary);
  font-style: italic;
  margin-bottom: 0.3em;
  font-weight: 300;
}

.paper-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  margin-top: 0.3em;
}

.resource-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 0.18em 0.5em;
  background: var(--color-tag-bg);
  color: var(--color-accent);
  border-radius: 3px;
  text-decoration: none;
  transition: background var(--transition-fast);
}
.resource-tag:hover { background: var(--color-tag-hover); color: var(--color-accent); }

/* Abstract */
.abstract-toggle {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 0.18em 0.5em;
  background: var(--color-tag-bg);
  color: var(--color-accent);
  border: none;
  border-radius: 3px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.2em;
  transition: background var(--transition-fast);
}
.abstract-toggle:hover { background: var(--color-tag-hover); }

.abstract-toggle .chevron {
  transition: transform var(--transition-med);
}
.abstract-toggle.open .chevron { transform: rotate(180deg); }

.abstract-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-med);
}

.abstract-content p {
  padding: 0.6rem 0 0.2rem;
  font-size: 0.88rem;
  color: var(--color-secondary);
  line-height: 1.65;
  font-weight: 300;
  border-top: 1px dashed var(--color-border);
  margin-top: 0.4rem;
}

/* ==========================================================================
   TALKS — timeline layout
   ========================================================================== */

.talks-section {
  margin-bottom: 2.2rem;
}

.talks-section > h2 {
  font-size: 1.35rem;
  margin-bottom: 1.2rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-accent);
}

/* Talks grouped by title */
.talk-grouped-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.talk-group {
  padding: 0.7rem 0 0.7rem 0.8rem;
  border-left: 2px solid transparent;
  transition: border-color var(--transition-med);
}

.talk-group:hover {
  border-left-color: var(--color-accent);
}

.talk-group + .talk-group {
  border-top: 1px solid var(--color-border-light);
}

.talk-group-title {
  font-weight: 500;
  font-size: 0.95rem;
  line-height: 1.4;
  margin-bottom: 0.25rem;
  color: var(--color-body);
}

.talk-venues {
  list-style: none;
  padding: 0;
  margin: 0;
}

.talk-venues li {
  font-size: 0.84rem;
  color: var(--color-secondary);
  font-weight: 300;
  line-height: 1.5;
  padding: 0.1rem 0;
}

.talk-venue-name {
  color: var(--color-secondary);
}

.talk-venue-year {
  font-variant-numeric: tabular-nums;
  color: var(--color-secondary);
}

.talk-links {
  margin-top: 0.2rem;
  display: flex;
  gap: 0.3rem;
}

/* ==========================================================================
   TEACHING
   ========================================================================== */

.teaching-section {
  margin-bottom: 1.8rem;
}

.teaching-section h2 {
  font-size: 1.2rem;
  margin-bottom: 0.6rem;
  padding-bottom: 0.25rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-accent);
}

.teaching-list {
  list-style: none;
  padding: 0;
}

.teaching-item {
  padding: 0.5rem 0;
  font-size: 0.92rem;
  line-height: 1.55;
}

.teaching-item + .teaching-item {
  border-top: 1px solid var(--color-border-light);
}

.course-code {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-accent);
}

.course-title { font-weight: 400; }

.rating {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--color-self);
  font-weight: 600;
  margin-left: 0.2em;
}

/* ==========================================================================
   VITA
   ========================================================================== */

.vita-section {
  margin-bottom: 2rem;
}

.vita-section h2 {
  font-size: 1.3rem;
  margin-bottom: 0.7rem;
  padding-bottom: 0.3rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-accent);
}

.vita-section h3 {
  font-size: 0.95rem;
  margin: 0.8rem 0 0.4rem;
  color: var(--color-secondary);
  font-weight: 500;
}

.vita-list {
  list-style: none;
  padding: 0;
}

.vita-item {
  padding: 0.4rem 0;
  font-size: 0.92rem;
  line-height: 1.55;
}

.vita-item + .vita-item {
  border-top: 1px solid var(--color-border-light);
}

.education-item { padding: 0.5rem 0; }

.refereeing-list {
  font-size: 0.9rem;
  color: var(--color-secondary);
  line-height: 1.65;
  font-weight: 300;
}

.music-list ul {
  list-style: disc;
  padding-left: 1.3em;
  margin-top: 0.25rem;
}

.music-list ul li {
  font-size: 0.88rem;
  padding: 0.1rem 0;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */

.site-footer {
  margin-top: 2.5rem;
  padding: 1.3rem 2rem;
  border-top: 1px solid var(--color-border-light);
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-muted);
  font-weight: 300;
}

.site-footer a { color: var(--color-muted); }
.site-footer a:hover { color: var(--color-secondary); }
.site-footer p + p { margin-top: 0.2em; }

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */

@media (max-width: 960px) {
  .hero-inner {
    grid-template-columns: 1fr 280px;
    gap: 2rem;
    padding: 2.5rem 2rem;
    min-height: auto;
  }
  .hero-role strong { font-size: 1.05rem; }
  .hero-image img { max-width: 260px; }
}

@media (max-width: 768px) {
  html { font-size: 16px; }

  .header-inner { padding: 0 1.5rem; }

  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
    padding: 2rem 1.5rem;
    gap: 1.5rem;
  }

  .hero-image { order: -1; }
  .hero-image img {
    max-width: 220px;
    margin: 0 auto;
    aspect-ratio: 1 / 1;
    border-radius: 50%;
  }

  .hero-role strong { font-size: 1rem; }
  .hero-bio { max-width: 100%; }

  /* Nav */
  .menu-toggle { display: flex; }

  .nav-links {
    display: none;
    flex-direction: column;
    gap: 0;
    position: absolute;
    top: 100%;
    left: 0; right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 0.5rem 1.5rem 0.8rem;
    box-shadow: 0 6px 20px rgba(0,0,0,0.04);
  }

  .nav-links.open { display: flex; }

  .nav-links a {
    display: block;
    padding: 0.55rem 0;
    font-size: 0.95rem;
    border-bottom: 1px solid var(--color-border-light);
  }
  .nav-links li:last-child a { border-bottom: none; }
  .main-nav { position: relative; }

  .recent-activity { padding: 1.8rem 1.5rem 1rem; }

  .container { padding: 0 1.5rem; }
  main > .container > h1 { font-size: 1.8rem; }
}

@media (max-width: 480px) {
  html { font-size: 15px; }

  .container, .header-inner { padding: 0 1rem; }
  .hero-inner { padding: 1.5rem 1rem; }
  .hero-role strong { font-size: 0.95rem; }
  .hero-image img { max-width: 180px; }

  .recent-activity { padding: 1.3rem 1rem 0.8rem; }
  main > .container > h1 { font-size: 1.5rem; }

  .talk-group { padding-left: 0.5rem; }
}

/* --- Print --------------------------------------------------------------- */

@media print {
  .site-header, .menu-toggle, .skip-link,
  .abstract-toggle, .site-footer { display: none !important; }
  body { background: #fff; color: #000; font-size: 12pt; }
  .hero { background: none; }
  .hero-inner { display: block; padding: 1rem 0; }
  .hero-image { display: none; }
  .paper-item { border: none; padding: 0.3rem 0; }
  .paper-item:hover { background: none; }
  a { color: #000; text-decoration: underline; }
}

/* --- Focus & Selection --------------------------------------------------- */

:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
::selection { background: rgba(160, 128, 54, 0.12); }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}