/* ============================================================
   Dr. Kashif — Academic personal site
   Palette: ink #0a0a0a · paper #fafafa · line #e5e5e5 · accent #db3356
   ============================================================ */

:root {
  --ink: #0a0a0a;
  --ink-2: #3d3d3d;
  --ink-3: #6e6e6e;
  --paper: #fafafa;
  --line: #e5e5e5;
  --line-dark: rgba(250, 250, 250, 0.12);
  --accent: #db3356;
  --serif: "Newsreader", "Georgia", serif;
  --sans: "Inter", -apple-system, "Segoe UI", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --gutter: clamp(1.5rem, 5vw, 4.8rem);
  --header-h: 5rem; /* refined at runtime by main.js; fallback if JS is off */
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-weight: 340;
  font-size: 1.125rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  padding-top: var(--header-h);
}

[id] { scroll-margin-top: calc(var(--header-h) + 0.75rem); }

::selection { background: var(--accent); color: var(--paper); }

/* Custom scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(10, 10, 10, 0.25); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: rgba(10, 10, 10, 0.45); }

a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- Layout shell ---------- */

.shell {
  max-width: 1200px;
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 0 clamp(1.25rem, 3vw, 3rem);
}

/* ---------- Header ---------- */

.site-header {
  border-bottom: 1px solid var(--line);
  padding: 1.4rem 0;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(250, 250, 250, 0.88);
  backdrop-filter: blur(10px) saturate(1.4);
  -webkit-backdrop-filter: blur(10px) saturate(1.4);
  z-index: 50;
}

.site-header .shell {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 2rem;
  flex-wrap: wrap;
}

.wordmark {
  font-family: var(--serif);
  font-weight: 480;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
}
.wordmark em { font-style: normal; color: var(--accent); }

.site-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  column-gap: 1.75rem;
  row-gap: 0.5rem;
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.site-nav a {
  color: var(--ink-3);
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  transition: color 250ms var(--ease), border-color 250ms var(--ease);
}
.site-nav a:hover { color: var(--ink); border-bottom-color: var(--accent); }
.site-nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--accent); }

.site-nav a.nav-cta {
  background: var(--accent);
  color: #fff;
  padding: 0.45em 1em;
  border-bottom: none;
  border-radius: 999px;
  transition: background 250ms var(--ease);
}
.site-nav a.nav-cta:hover { background: #b12a45; color: #fff; }

/* ---------- Hero ---------- */

.hero { padding: clamp(4rem, 10vh, 7.5rem) 0 clamp(3rem, 7vh, 5rem); }

.hero-kicker {
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.6rem;
  display: block;
}

.hero-name {
  font-weight: 300;
  font-size: clamp(2.6rem, 6vw, 4.6rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin-bottom: 1.4rem;
}

.hero-role {
  font-size: clamp(1.15rem, 2vw, 1.4rem);
  color: var(--ink-2);
  font-style: italic;
  margin-bottom: 1.8rem;
}

.hero-bio { color: var(--ink-2); max-width: 34em; }
.hero-bio a { border-bottom: 1px solid var(--accent); transition: color 200ms var(--ease); }
.hero-bio a:hover { color: var(--accent); }

.hero-left { grid-column: span 7; }
.hero-right { grid-column: 9 / span 4; align-self: end; }

.hero-cta { margin-top: 2.2rem; }
.btn {
  display: inline-block;
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  background: var(--accent);
  color: #fff;
  padding: 0.95em 1.7em;
  border-radius: 999px;
  transition: background 250ms var(--ease);
}
.btn:hover { background: #b12a45; }

/* Metadata list (label : value rows) */
.meta-list {
  list-style: none;
  font-family: var(--sans);
  font-size: 0.85rem;
  border-top: 1px solid var(--line);
}
.meta-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1.5rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--line);
}
.meta-list .k {
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  flex-shrink: 0;
}
.meta-list .v { text-align: right; color: var(--ink-2); }
.meta-list .v a { border-bottom: 1px solid var(--line); transition: border-color 200ms var(--ease), color 200ms var(--ease); }
.meta-list .v a:hover { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- Sections ---------- */

.section { padding: clamp(3rem, 8vh, 5.5rem) 0; }
.section + .section { border-top: 1px solid var(--line); }

.section-head {
  display: flex;
  align-items: baseline;
  gap: 1.2rem;
  margin-bottom: clamp(2rem, 5vh, 3.2rem);
}
.section-index {
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--accent);
}
.section-title {
  font-weight: 340;
  font-size: clamp(1.7rem, 3.4vw, 2.4rem);
  letter-spacing: -0.015em;
  line-height: 1.15;
}

.section-lede {
  grid-column: span 5;
  color: var(--ink-2);
}
.section-lede p + p { margin-top: 1em; }

/* Numbered research rows */
.topic-list { list-style: none; grid-column: 7 / span 6; border-top: 1px solid var(--line); counter-reset: topic; }
.topic-list li {
  counter-increment: topic;
  display: grid;
  grid-template-columns: 3.2rem 1fr;
  gap: 1rem;
  padding: 1.4rem 0;
  border-bottom: 1px solid var(--line);
}
.topic-list li::before {
  content: counter(topic, decimal-leading-zero);
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--accent);
  padding-top: 0.45em;
}
.topic-list h3 { font-weight: 420; font-size: 1.22rem; letter-spacing: -0.01em; margin-bottom: 0.3rem; }
.topic-list p { font-size: 1rem; color: var(--ink-3); }

/* ---------- Dark publications section ---------- */

.section-dark { background: var(--ink); color: var(--paper); }
.section-dark .section-title { color: var(--paper); }
.section-dark .section-lede { color: rgba(250, 250, 250, 0.6); }

.pub-list { list-style: none; grid-column: 7 / span 6; border-top: 1px solid var(--line-dark); }
.pub-list li {
  display: grid;
  grid-template-columns: 4rem 1fr;
  gap: 1.25rem;
  padding: 1.35rem 0;
  border-bottom: 1px solid var(--line-dark);
}
.pub-year {
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--accent);
  padding-top: 0.4em;
}
.pub-title { font-weight: 380; font-size: 1.12rem; line-height: 1.45; }
.pub-title a { border-bottom: 1px solid transparent; transition: border-color 200ms var(--ease), color 200ms var(--ease); }
.pub-title a:hover { color: var(--accent); border-bottom-color: var(--accent); }
.pub-venue {
  font-family: var(--sans);
  font-size: 0.8rem;
  color: rgba(250, 250, 250, 0.45);
  margin-top: 0.35rem;
  font-style: normal;
}

/* ---------- Teaching rows ---------- */

.course-list { list-style: none; grid-column: 7 / span 6; border-top: 1px solid var(--line); }
.course-list li {
  display: grid;
  grid-template-columns: 7rem 1fr auto;
  gap: 1.25rem;
  align-items: baseline;
  padding: 1.2rem 0;
  border-bottom: 1px solid var(--line);
}
.course-code {
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--ink-3);
}
.course-name { font-weight: 400; font-size: 1.1rem; }
.course-term {
  font-family: var(--sans);
  font-size: 0.75rem;
  color: var(--ink-3);
}

/* ---------- Callout band ---------- */

.band {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: clamp(3rem, 7vh, 4.5rem) 0;
  text-align: left;
}
.band p {
  font-size: clamp(1.4rem, 3vw, 2rem);
  font-weight: 320;
  line-height: 1.35;
  letter-spacing: -0.01em;
  max-width: 26em;
}
.band a {
  color: var(--accent);
  border-bottom: 1px solid var(--accent);
  transition: opacity 200ms var(--ease);
}
.band a:hover { opacity: 0.65; }

/* ---------- Footer ---------- */

.site-footer { padding: 3rem 0 3.5rem; }
.site-footer .shell {
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  flex-wrap: wrap;
  font-family: var(--sans);
  font-size: 0.78rem;
  color: var(--ink-3);
}
.site-footer a { border-bottom: 1px solid var(--line); transition: color 200ms var(--ease), border-color 200ms var(--ease); }
.site-footer a:hover { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- Students page ---------- */

.page-hero { padding: clamp(3.5rem, 9vh, 6.5rem) 0 clamp(2.5rem, 6vh, 4rem); }
.page-hero h1 {
  font-weight: 300;
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  max-width: 15em;
}
.page-hero .lede {
  margin-top: 1.6rem;
  font-size: clamp(1.1rem, 1.8vw, 1.3rem);
  color: var(--ink-2);
  max-width: 36em;
}

/* Status tags */
.tag {
  display: inline-block;
  font-family: var(--sans);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.32em 0.9em;
  border: 1px solid var(--ink);
  border-radius: 999px;
}
.tag.open { border-color: var(--accent); color: var(--accent); }

/* Opening rows */
.opening-list { list-style: none; grid-column: 7 / span 6; border-top: 1px solid var(--line); }
.opening-list li {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--line);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.4rem 1.5rem;
  align-items: baseline;
}
.opening-list h3 { font-weight: 420; font-size: 1.2rem; letter-spacing: -0.01em; }
.opening-list p { grid-column: 1 / -1; font-size: 1rem; color: var(--ink-3); }

/* Steps (how to reach out) */
.steps { list-style: none; grid-column: 7 / span 6; counter-reset: step; border-top: 1px solid var(--line); }
.steps > li {
  counter-increment: step;
  display: grid;
  grid-template-columns: 3.2rem 1fr;
  gap: 1rem;
  padding: 1.3rem 0;
  border-bottom: 1px solid var(--line);
}
.steps > li::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--accent);
  padding-top: 0.45em;
}
.steps h3 { font-weight: 420; font-size: 1.12rem; margin-bottom: 0.25rem; }
.steps p { font-size: 1rem; color: var(--ink-3); }
.steps code {
  font-family: "SFMono-Regular", "Menlo", monospace;
  font-size: 0.82em;
  background: rgba(10, 10, 10, 0.05);
  padding: 0.1em 0.45em;
  border-radius: 4px;
}

/* FAQ accordions */
.faq { grid-column: 7 / span 6; border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1.5rem;
  padding: 1.3rem 0;
  font-weight: 420;
  font-size: 1.12rem;
  letter-spacing: -0.01em;
  transition: color 200ms var(--ease);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  font-family: var(--sans);
  font-weight: 400;
  font-size: 1.1rem;
  color: var(--accent);
  transition: transform 300ms var(--ease);
  flex-shrink: 0;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq summary:hover { color: var(--accent); }
.faq details .answer { padding: 0 0 1.4rem; color: var(--ink-2); font-size: 1.02rem; max-width: 38em; }
.faq details .answer a { border-bottom: 1px solid var(--accent); }
.faq details .answer a:hover { color: var(--accent); }

.doc-list {
  list-style: none;
  margin: 0.5rem 0 0;
}
.doc-list li {
  position: relative;
  padding-left: 1.3rem;
  font-family: var(--sans);
  font-size: 0.92rem;
  line-height: 1.5;
  margin-bottom: 0.45rem;
}
.doc-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 7px;
  height: 7px;
  background: var(--accent);
}

.doc-details { margin-top: 0.6rem; }
.doc-details summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--sans);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--ink-2);
  padding: 0.35rem 0;
}
.doc-details summary::-webkit-details-marker { display: none; }
.doc-details summary::after {
  content: "+";
  color: var(--accent);
  font-size: 1.05rem;
  transition: transform 300ms var(--ease);
  flex-shrink: 0;
}
.doc-details[open] summary::after { transform: rotate(45deg); }
.doc-details summary:hover { color: var(--accent); }
.doc-details .doc-list { margin-top: 0.3rem; }

.doc-img {
  display: block;
  width: min(200px, 60%);
  height: auto;
  margin-top: 0.5rem;
  border: 1px solid var(--line);
}

/* ---------- Scroll reveal ---------- */

.reveal {
  opacity: 0;
  filter: blur(10px);
  transform: translateY(14px);
  transition: opacity 700ms var(--ease), filter 700ms var(--ease), transform 700ms var(--ease);
}
.reveal.is-visible { opacity: 1; filter: blur(0); transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; filter: none; transform: none; transition: none; }
  * { transition-duration: 0.01ms !important; }
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .site-header .shell { gap: 0.75rem; }
  .site-nav { column-gap: 1.1rem; }
  .hero-left, .hero-right,
  .section-lede, .topic-list, .pub-list, .course-list,
  .opening-list, .steps, .faq { grid-column: 1 / -1; }
  .hero-right { margin-top: 2.5rem; align-self: start; }
  .section-lede { margin-bottom: 2.2rem; }
  .course-list li { grid-template-columns: 5.5rem 1fr; }
  .course-term { display: none; }
}