/* ============================================
   ANUSHTHA MISHRA — UX RESEARCHER PORTFOLIO
   Design tokens: clinical precision + warmth
   ============================================ */

/* --- TOKENS --- */
:root {
  --bg:          #F7F7F5;
  --ink:         #141414;
  --ink-muted:   #5A5A58;
  --ink-faint:   #9A9A98;
  --teal:        #1A6B6B;
  --teal-light:  #E8F4F4;
  --stone:       #E8E4DC;
  --white:       #FFFFFF;

  --serif:       'DM Serif Display', Georgia, serif;
  --sans:        'Inter', system-ui, sans-serif;

  --step-0:  clamp(0.875rem, 1.5vw, 1rem);
  --step-1:  clamp(1rem,     2vw,   1.25rem);
  --step-2:  clamp(1.25rem,  2.5vw, 1.75rem);
  --step-3:  clamp(1.75rem,  4vw,   2.5rem);
  --step-4:  clamp(2.5rem,   6vw,   4rem);
  --step-5:  clamp(3.5rem,   9vw,   6.5rem);

  --space-xs:  0.5rem;
  --space-s:   1rem;
  --space-m:   2rem;
  --space-l:   4rem;
  --space-xl:  7rem;
  --space-xxl: 11rem;

  --radius:    4px;
  --radius-m:  8px;
  --transition: 220ms ease;
}

/* --- RESET --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: var(--step-0);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

/* --- REVEAL ANIMATION (disabled) --- */
.reveal {
  opacity: 1;
  transform: none;
}

/* --- NAV --- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem var(--space-m);
  background: rgba(247, 247, 245, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}
.nav.scrolled { border-bottom-color: var(--stone); }
.nav-logo {
  font-family: var(--serif);
  font-size: 1.4rem;
  color: var(--ink);
  letter-spacing: -0.01em;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-m);
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--ink-muted);
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--ink); }
.nav-cta {
  color: var(--white) !important;
  background: var(--teal);
  padding: 0.45rem 1.1rem;
  border-radius: var(--radius);
  transition: background var(--transition) !important;
}
.nav-cta:hover { background: #145555 !important; }
.nav-hamburger {
  display: none;
  background: none;
  border: none;
  font-size: 1.4rem;
  cursor: pointer;
  color: var(--ink);
}

/* --- MOBILE MENU --- */
.mobile-menu {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 200;
  background: var(--bg);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-m);
}
.mobile-menu.open { display: flex; }
.mobile-menu ul { display: flex; flex-direction: column; align-items: center; gap: var(--space-m); }
.mobile-menu a {
  font-family: var(--serif);
  font-size: var(--step-3);
  color: var(--ink);
}
.mobile-menu-close {
  position: absolute;
  top: 1.5rem; right: 1.5rem;
  background: none;
  border: none;
  font-size: 2rem;
  cursor: pointer;
  color: var(--ink);
}

/* --- SHARED LAYOUT --- */
section {
  padding: var(--space-xl) var(--space-m);
  max-width: 1100px;
  margin: 0 auto;
}
.section-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: var(--space-s);
}
.section-header { margin-bottom: var(--space-l); }
.section-header h2 {
  font-family: var(--serif);
  font-size: var(--step-3);
  line-height: 1.15;
  max-width: 560px;
}

/* --- HERO --- */
.hero {
  padding-top: calc(var(--space-xl) + 4rem);
  padding-bottom: var(--space-xl);
  min-height: 92vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.hero-eyebrow {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--ink-muted);
  margin-bottom: var(--space-m);
}
.hero-headline {
  font-family: var(--serif);
  font-size: var(--step-5);
  line-height: 1.08;
  letter-spacing: -0.02em;
  max-width: 820px;
  margin-bottom: var(--space-m);
}
.hero-headline em {
  font-style: italic;
  color: var(--teal);
}
.hero-sub {
  max-width: 560px;
  font-size: var(--step-1);
  color: var(--ink-muted);
  line-height: 1.7;
  margin-bottom: var(--space-l);
}
.hero-actions {
  display: flex;
  gap: var(--space-s);
  flex-wrap: wrap;
  margin-bottom: var(--space-xl);
}

/* Buttons */
.btn-primary {
  display: inline-block;
  background: var(--teal);
  color: var(--white);
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 500;
  font-size: 0.9rem;
  transition: background var(--transition), transform var(--transition);
}
.btn-primary:hover { background: #145555; transform: translateY(-1px); }
.btn-ghost {
  display: inline-block;
  border: 1.5px solid var(--ink);
  color: var(--ink);
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 500;
  font-size: 0.9rem;
  transition: border-color var(--transition), color var(--transition), transform var(--transition);
}
.btn-ghost:hover { border-color: var(--teal); color: var(--teal); transform: translateY(-1px); }
.btn-download {
  display: inline-block;
  background: var(--teal-light);
  color: var(--teal);
  border: 1.5px solid rgba(26,107,107,0.18);
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.9rem;
  transition: background var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
}
.btn-download:hover {
  background: #d9eeee;
  border-color: rgba(26,107,107,0.32);
  color: var(--teal);
  transform: translateY(-1px);
}
.btn-download:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 3px;
}
.btn-on-dark {
  display: inline-block;
  background: var(--white);
  color: var(--ink);
  border: 1.5px solid var(--white);
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.9rem;
  transition: background var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
}
.btn-on-dark:hover {
  background: var(--teal-light);
  border-color: var(--teal-light);
  color: var(--teal);
  transform: translateY(-1px);
}
.btn-on-dark:focus-visible {
  outline: 2px solid var(--teal-light);
  outline-offset: 3px;
}
.btn-sm { padding: 0.5rem 1.1rem; font-size: 0.85rem; }

/* Hero stats */
.hero-stats {
  display: flex;
  gap: var(--space-m);
  align-items: center;
  flex-wrap: wrap;
  padding-top: var(--space-l);
  border-top: 1px solid var(--stone);
}
.stat { display: flex; flex-direction: column; gap: 0.2rem; }
.stat-number {
  font-family: var(--serif);
  font-size: var(--step-2);
  color: var(--ink);
  line-height: 1;
}
.stat-label {
  font-size: 0.75rem;
  color: var(--ink-muted);
  max-width: 140px;
}
.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--stone);
}

/* --- DIFFERENTIATORS --- */
.differentiators {
  background: var(--stone);
  max-width: 100%;
  padding: var(--space-l) var(--space-m);
}
.differentiators > * { max-width: 1100px; margin-left: auto; margin-right: auto; }
.differentiators .section-label { max-width: 1100px; margin: 0 auto var(--space-m); }
.diff-grid {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-m);
}
.diff-card {
  background: var(--white);
  border-radius: var(--radius-m);
  padding: var(--space-m);
  display: flex;
  flex-direction: column;
  gap: var(--space-s);
}
.diff-icon { font-size: 1.5rem; }
.diff-card h3 {
  font-family: var(--serif);
  font-size: var(--step-1);
}
.diff-card p {
  font-size: 0.875rem;
  color: var(--ink-muted);
  line-height: 1.65;
}

/* --- WORK / PROJECT CARDS --- */
.work { padding-top: var(--space-l); padding-bottom: var(--space-l); }
.project-card {
  display: block;
  border: 1px solid var(--stone);
  border-radius: var(--radius-m);
  padding: var(--space-l);
  margin-bottom: var(--space-m);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.project-card-link { cursor: pointer; }
.project-card:hover,
.project-card-link:focus-visible {
  border-color: var(--teal);
  box-shadow: 0 4px 24px rgba(26,107,107,0.08);
}
.project-card-link:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 4px;
}
.project-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: var(--space-m);
}
.project-tag {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--teal);
  background: var(--teal-light);
  padding: 0.25rem 0.65rem;
  border-radius: 100px;
}
.project-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-l);
  align-items: center;
}
.project-eyebrow {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 0.5rem;
}
.project-text h3 {
  font-family: var(--serif);
  font-size: var(--step-2);
  line-height: 1.25;
  margin-bottom: var(--space-s);
}
.project-desc {
  color: var(--ink-muted);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: var(--space-m);
}
.project-methods {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: var(--space-m);
}
.project-methods span {
  font-size: 0.75rem;
  color: var(--ink-muted);
  border: 1px solid var(--stone);
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
}
.project-link {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--teal);
  transition: gap var(--transition);
}
.project-link:hover { text-decoration: underline; }

/* Project visuals */
.project-visual {
  border-radius: var(--radius-m);
  overflow: hidden;
}
.insight-card {
  background: var(--ink);
  color: var(--white);
  padding: var(--space-m);
  border-radius: var(--radius-m);
}
.insight-label {
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal-light);
  margin-bottom: 0.75rem;
  opacity: 0.8;
}
.insight-quote {
  font-family: var(--serif);
  font-size: var(--step-1);
  font-style: italic;
  line-height: 1.5;
  margin-bottom: 0.75rem;
}
.insight-attribution {
  font-size: 0.75rem;
  color: var(--ink-faint);
  color: rgba(255,255,255,0.5);
}
.stat-visual {
  background: var(--teal-light);
  border: 1px solid rgba(26,107,107,0.15);
  border-radius: var(--radius-m);
  padding: var(--space-m);
  text-align: center;
}
.big-stat {
  font-family: var(--serif);
  font-size: clamp(4rem, 10vw, 7rem);
  line-height: 1;
  color: var(--teal);
}
.big-stat span { font-size: 0.4em; vertical-align: super; }
.stat-visual p {
  font-size: 0.85rem;
  color: var(--ink-muted);
  margin-top: var(--space-s);
  max-width: 240px;
  margin-left: auto;
  margin-right: auto;
}

/* WIP card */
.project-card--wip {
  border-style: dashed;
  background: transparent;
}
.project-card--wip:hover { box-shadow: none; }
.wip-inner { max-width: 600px; }
.wip-inner h3 {
  font-family: var(--serif);
  font-size: var(--step-2);
  margin: 0.5rem 0;
}
.wip-inner p { color: var(--ink-muted); font-size: 0.9rem; }

/* --- METHODS --- */
.methods {
  background: var(--ink);
  color: var(--white);
  max-width: 100%;
  padding: var(--space-xl) var(--space-m);
}
.methods > * { max-width: 1100px; margin-left: auto; margin-right: auto; }
.methods .section-label { max-width: 1100px; margin: 0 auto 0.5rem; color: var(--teal-light); opacity: 0.7; }
.methods h2 {
  font-family: var(--serif);
  font-size: var(--step-3);
  max-width: 1100px;
  margin: 0 auto var(--space-l);
}
.methods-grid {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-l);
}
.method-group h4 {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--teal-light);
  opacity: 0.7;
  margin-bottom: var(--space-s);
}
.method-group ul { display: flex; flex-direction: column; gap: 0.5rem; }
.method-group li {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.75);
  padding-left: 0.9rem;
  position: relative;
}
.method-group li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: var(--teal);
  font-size: 0.7rem;
}

/* --- LAB --- */
.lab {
  padding: var(--space-l) var(--space-m);
  max-width: 100%;
  background: var(--ink);
  color: var(--white);
}
.lab-inner {
  max-width: 760px;
  margin: 0 auto;
}
.lab-text .section-label { margin-bottom: var(--space-s); }
.lab-text h2 {
  font-family: var(--serif);
  font-size: var(--step-3);
  line-height: 1.2;
  margin-bottom: var(--space-m);
}
.lab-text > p {
  color: rgba(255,255,255,0.72);
  margin-bottom: var(--space-m);
}
.lab-experiment {
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: var(--radius-m);
  padding: var(--space-m);
  background: rgba(255,255,255,0.05);
}
.experiment-status {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #22a85a;
  margin-bottom: 0.75rem;
}
.lab-experiment h3 {
  font-family: var(--serif);
  font-size: var(--step-2);
  margin-bottom: 0.5rem;
}
.lab-experiment p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.68);
  margin-bottom: var(--space-m);
}
.experiment-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: var(--space-m);
}
.experiment-stack span {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  background: rgba(255,255,255,0.1);
  padding: 0.25rem 0.65rem;
  border-radius: 100px;
  color: rgba(255,255,255,0.72);
}

/* Terminal */
.terminal {
  background: #0D1117;
  border-radius: var(--radius-m);
  overflow: hidden;
  font-family: 'Courier New', monospace;
  font-size: 0.82rem;
  box-shadow: 0 12px 40px rgba(0,0,0,0.18);
}
.terminal-bar {
  background: #1C2128;
  padding: 0.65rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.dot { width: 12px; height: 12px; border-radius: 50%; }
.dot-red    { background: #FF5F57; }
.dot-yellow { background: #FEBC2E; }
.dot-green  { background: #28C840; }
.terminal-title {
  margin-left: 0.5rem;
  font-size: 0.72rem;
  color: rgba(255,255,255,0.4);
}
.terminal-body {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  line-height: 1.6;
}
.terminal-body p { color: rgba(255,255,255,0.85); }
.t-comment { color: #6A7F6C; }
.t-key     { color: #79B8FF; }
.t-op      { color: rgba(255,255,255,0.5); }
.t-str     { color: #9ECBFF; }

/* --- ABOUT --- */
.about { padding: var(--space-l) var(--space-m); }
.about-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(320px, 0.92fr);
  gap: var(--space-xl);
  align-items: start;
}
.about-text .section-label { margin-bottom: var(--space-s); }
.about-text h2 {
  font-family: var(--serif);
  font-size: var(--step-3);
  line-height: 1.2;
  margin-bottom: var(--space-m);
}
.about-text p {
  color: var(--ink-muted);
  margin-bottom: var(--space-m);
  font-size: 0.95rem;
}
.about-personal {
  font-style: italic;
  color: var(--ink-faint) !important;
  font-size: 0.875rem !important;
}
.about-credentials {
  display: flex;
  flex-direction: column;
  gap: var(--space-m);
  padding-top: 0.5rem;
}
.credential {
  display: flex;
  gap: var(--space-m);
  align-items: flex-start;
  padding-bottom: var(--space-m);
  border-bottom: 1px solid var(--stone);
}
.credential:last-child { border-bottom: none; }
.credential-year {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--teal);
  white-space: nowrap;
  padding-top: 0.25rem;
  min-width: 60px;
}
.credential strong { display: block; margin-bottom: 0.2rem; font-size: 0.9rem; }
.credential p { font-size: 0.8rem; color: var(--ink-muted); }
.about-flow {
  position: relative;
  gap: 0;
  margin-top: 2.55rem;
  padding: 0.25rem 0 0.25rem 1.1rem;
}
.about-flow::before {
  content: '';
  position: absolute;
  left: 0.15rem;
  top: 0.5rem;
  bottom: 0.5rem;
  width: 1px;
  background: var(--stone);
}
.flow-item {
  position: relative;
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: var(--space-m);
  padding: 0 0 var(--space-l);
}
.flow-item:last-child { padding-bottom: 0; }
.flow-item::before {
  content: '';
  position: absolute;
  left: -1.15rem;
  top: 0.22rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 5px var(--bg);
}
.flow-year {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--teal);
  white-space: nowrap;
  padding-top: 0.05rem;
}
.flow-content {
  position: relative;
  padding-left: var(--space-m);
}
.flow-content::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.42rem;
  width: 12px;
  height: 1px;
  background: var(--stone);
}
.flow-content strong {
  display: block;
  font-size: 0.92rem;
  line-height: 1.35;
  margin-bottom: 0.45rem;
}
.flow-branch {
  font-size: 0.82rem !important;
  color: var(--ink) !important;
  line-height: 1.55;
  margin-bottom: 0.25rem !important;
}
.flow-learning {
  font-size: 0.8rem !important;
  color: var(--ink-muted) !important;
  line-height: 1.6;
  margin-bottom: 0 !important;
}

/* --- CONTACT --- */
.contact {
  background: var(--teal);
  color: var(--white);
  max-width: 100%;
  padding: var(--space-xl) var(--space-m);
  text-align: center;
}
.contact .section-label { color: rgba(255,255,255,0.6); }
.contact h2 {
  font-family: var(--serif);
  font-size: var(--step-3);
  max-width: 600px;
  margin: 0 auto var(--space-m);
  line-height: 1.2;
}
.contact p {
  color: rgba(255,255,255,0.75);
  max-width: 480px;
  margin: 0 auto var(--space-l);
}
.contact-links {
  display: flex;
  gap: var(--space-s);
  justify-content: center;
  flex-wrap: wrap;
}
.contact .btn-primary {
  background: var(--white);
  color: var(--teal);
}
.contact .btn-primary:hover { background: var(--stone); }
.contact .btn-ghost {
  border-color: rgba(255,255,255,0.5);
  color: var(--white);
}
.contact .btn-ghost:hover { border-color: var(--white); }

/* --- FOOTER --- */
.footer {
  padding: var(--space-m);
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--stone);
  max-width: 1100px;
  margin: 0 auto;
  font-size: 0.75rem;
  color: var(--ink-faint);
}

/* --- BACK TO TOP --- */
.back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 1000;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  min-width: 48px;
  min-height: 48px;
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: 50%;
  background: #141414;
  color: var(--white);
  box-shadow: 0 16px 40px rgba(20,20,20,0.34);
  backdrop-filter: blur(12px);
  font-size: 1.45rem;
  font-weight: 700;
  line-height: 1;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
  transition: opacity var(--transition), color var(--transition), border-color var(--transition), background var(--transition), transform var(--transition), box-shadow var(--transition);
}
.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}
.back-to-top:hover,
.back-to-top:focus-visible {
  color: var(--white);
  border-color: var(--teal);
  background: var(--teal);
  box-shadow: 0 18px 44px rgba(20,20,20,0.32);
  transform: translateY(-3px);
}
.back-to-top:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 3px;
}

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
  :root {
    --space-xl: 4rem;
    --space-xxl: 6rem;
  }
  .nav-links { display: none; }
  .nav-hamburger { display: block; }

  .project-content { grid-template-columns: 1fr; }
  .project-visual { display: none; }

  .lab-inner { grid-template-columns: 1fr; }
  .lab-visual { display: none; }

  .about-inner { grid-template-columns: 1fr; }
  .about-flow { margin-top: 0; }

  .hero-stats { gap: var(--space-m); }
  .stat-divider { display: none; }

  .footer { flex-direction: column; gap: 0.5rem; text-align: center; }

  .back-to-top {
    right: 1rem;
    bottom: 1rem;
    width: 44px;
    height: 44px;
  }

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

@media (max-width: 480px) {
  section { padding: var(--space-l) var(--space-s); }
}