/* =========
   Base
   ========= */

:root{
  --bg: #070b14;
  --bg-2: #0b1220;
  --text: #e7ecff;
  --muted: rgba(231,236,255,.72);
  --muted-2: rgba(231,236,255,.55);

  --card: rgba(255,255,255,.06);
  --card-2: rgba(255,255,255,.08);
  --border: rgba(255,255,255,.12);

  --accent: #7c3aed;
  --accent-2: #22d3ee;
  --good: #34d399;

  --shadow: 0 20px 60px rgba(0,0,0,.45);

  --radius: 18px;
  --radius-sm: 14px;

  --container: 1120px;
}

html[data-theme="light"]{
  --bg: #f6f7ff;
  --bg-2: #ffffff;
  --text: #0b1220;
  --muted: rgba(11,18,32,.74);
  --muted-2: rgba(11,18,32,.58);

  --card: rgba(11,18,32,.04);
  --card-2: rgba(11,18,32,.06);
  --border: rgba(11,18,32,.12);

  --shadow: 0 20px 60px rgba(2,6,23,.12);
}

*{ box-sizing: border-box; }
html, body{ height: 100%; }
html{ scroll-behavior: smooth; }
body{
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  /* Base page background. Decorative gradients live on the fixed .bg layer
     so they don't "shift" as you scroll (Safari can make this very noticeable). */
  background: var(--bg-2);
  overflow-x: hidden;
}

a{ color: inherit; text-decoration: none; }
a:hover{ text-decoration: underline; text-underline-offset: 4px; }

code{
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  background: var(--card);
  border: 1px solid var(--border);
  padding: 0.15em 0.45em;
  border-radius: 10px;
}

.container{
  width: min(var(--container), calc(100% - 2rem));
  margin: 0 auto;
}

.skip-link{
  position: absolute;
  top: -60px;
  left: 16px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  padding: 10px 14px;
  border-radius: 12px;
  color: var(--text);
  z-index: 1000;
}
.skip-link:focus{ top: 14px; }

/* =========
   Background ornaments
   ========= */

.bg{
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  /* Fixed gradients = continuous background while scrolling */
  background:
    radial-gradient(1200px 800px at 20% 0%, rgba(124,58,237,.26), transparent 55%),
    radial-gradient(900px 700px at 80% 10%, rgba(34,211,238,.20), transparent 55%),
    linear-gradient(180deg, var(--bg), var(--bg-2));
}
.blob{
  position: absolute;
  filter: blur(45px);
  opacity: .6;
  transform: translateZ(0);
}
.blob-a{
  width: 520px;
  height: 520px;
  left: -140px;
  top: -160px;
  background: radial-gradient(circle at 30% 30%, rgba(124,58,237,.9), rgba(124,58,237,0) 65%);
}
.blob-b{
  width: 500px;
  height: 500px;
  right: -160px;
  top: -120px;
  background: radial-gradient(circle at 70% 30%, rgba(34,211,238,.8), rgba(34,211,238,0) 68%);
}
.grid{
  position: absolute;
  inset: 0;
  opacity: .08;
  background-image:
    linear-gradient(to right, rgba(255,255,255,.22) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,.22) 1px, transparent 1px);
  background-size: 90px 90px;
  mask-image: radial-gradient(circle at 50% 25%, black 0%, transparent 85%);
  -webkit-mask-image: radial-gradient(circle at 50% 25%, black 0%, transparent 85%);
}

/* =========
   Header / nav
   ========= */

.site-header{
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(18px);
  background: linear-gradient(180deg, rgba(0,0,0,.35), rgba(0,0,0,0));
  border-bottom: 1px solid rgba(255,255,255,.08);
}
html[data-theme="light"] .site-header{
  background: linear-gradient(180deg, rgba(255,255,255,.80), rgba(255,255,255,.35));
  border-bottom: 1px solid rgba(11,18,32,.10);
}

.header-inner{
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
  gap: 14px;
}

.logo{
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none !important;
  user-select: none;
}
.logo-mark{
  width: 40px;
  height: 40px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  font-weight: 800;
  letter-spacing: .02em;
  color: white;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 12px 30px rgba(124,58,237,.35);
}
.logo-text{
  font-weight: 700;
  letter-spacing: .01em;
}

.nav{
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}
.nav a{
  color: var(--muted);
  font-weight: 500;
  font-size: 14px;
  padding: 8px 10px;
  border-radius: 12px;
}
.nav a:hover{
  background: var(--card);
  color: var(--text);
  text-decoration: none;
}
.nav a.active{
  background: var(--card-2);
  color: var(--text);
  border: 1px solid var(--border);
}

.actions{
  display: flex;
  gap: 10px;
  align-items: center;
}

/* =========
   Buttons
   ========= */

.btn{
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 16px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  font-weight: 600;
  text-decoration: none !important;
  box-shadow: none;
}
.btn:hover{
  background: var(--card-2);
  transform: translateY(-1px);
}
.btn:active{ transform: translateY(0); }

.btn.primary{
  border-color: rgba(124,58,237,.55);
  background: linear-gradient(135deg, rgba(124,58,237,.92), rgba(34,211,238,.40));
  box-shadow: 0 20px 55px rgba(124,58,237,.26);
}

.btn.small{ padding: 10px 12px; font-size: 14px; border-radius: 13px; }
.btn.ghost{ background: transparent; }

.icon-btn{
  width: 42px;
  height: 42px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  cursor: pointer;
}
.icon-btn:hover{ background: var(--card-2); }

.icon{ font-size: 18px; }

/* =========
   Sections
   ========= */

.section{ padding: 34px 0; }


.hero{ padding: 72px 0 36px; display: grid; grid-template-columns: 1.25fr .85fr; gap: 26px; align-items: start; }

.section-head{
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 18px;
}
.section-head h2{ margin: 0; font-size: 30px; letter-spacing: -0.02em; }
.section-head p{ margin: 0; color: var(--muted); }

.eyebrow{
  color: var(--muted);
  font-weight: 600;
  letter-spacing: .03em;
  text-transform: uppercase;
  font-size: 12px;
  margin: 0 0 10px;
}

.hero-title{
  margin: 0;
  font-size: clamp(40px, 4vw, 56px);
  letter-spacing: -0.03em;
  line-height: 1.02;
}

.hero-subtitle{
  margin: 16px 0 0;
  font-size: 18px;
  color: var(--muted);
  line-height: 1.5;
}
.role{
  color: var(--text);
  font-weight: 700;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.caret{
  margin-left: 6px;
  color: var(--muted);
  animation: blink 1.1s infinite;
}
@keyframes blink{ 0%, 49%{ opacity: 1; } 50%, 100%{ opacity: 0; } }

.hero-summary{
  margin: 16px 0 0;
  font-size: 16px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 70ch;
}

.hero-cta{
  margin-top: 22px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.hero-meta{ margin-top: 18px; display: grid; gap: 10px; }

.meta-row{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.pill{
  display: inline-flex;
  gap: 8px;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  font-weight: 600;
  font-size: 13px;
}

.social-row{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.social-row a{
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--card);
  font-weight: 600;
  font-size: 14px;
  text-decoration: none !important;
}
.social-row a:hover{ background: var(--card-2); }
.social-row .dot{
  width: 9px;
  height: 9px;
  border-radius: 99px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}

.stats{
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0,1fr));
  gap: 10px;
}
.stat{
  border-radius: 16px;
  border: 1px solid var(--border);
  background: var(--card);
  padding: 12px;
}
.stat .k{
  font-weight: 800;
  font-size: 22px;
  letter-spacing: -0.02em;
}
.stat .l{
  color: var(--muted);
  font-weight: 600;
  font-size: 12px;
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: .05em;
}

.hero-right{ display: grid; gap: 14px; }
.card{
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--card);
  padding: 16px;
  box-shadow: var(--shadow);
}
.glass{
  background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,.04));
}
.card-head{ display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.card h3{ margin: 0; letter-spacing: -0.01em; }
.muted{ color: var(--muted); }
.small{ font-size: 13px; }
.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;
}

.bullets{
  margin: 12px 0 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.6;
}
.bullets li{ margin: 8px 0; }

.chips{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 12px;
}
.chip{
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  cursor: pointer;
  font-weight: 700;
  font-size: 13px;
  user-select: none;
}
.chip:hover{ background: var(--card-2); color: var(--text); }
.chip.active{
  background: linear-gradient(135deg, rgba(124,58,237,.45), rgba(34,211,238,.22));
  color: var(--text);
  border-color: rgba(124,58,237,.55);
}

/* =========
   About
   ========= */

.about-grid{
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 14px;
}
.about-card h3{ margin: 0 0 10px; }
.about-card p{ margin: 0; color: var(--muted); line-height: 1.7; }

/* =========
   Skills
   ========= */

.skills-grid{
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}
.skill-block h3{ margin: 0 0 12px; }
.skill-list{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.skill{
  padding: 9px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  font-weight: 700;
  font-size: 13px;
}

/* =========
   Projects + Research
   ========= */

.filters{
  padding: 14px;
  box-shadow: none;
  margin-bottom: 14px;
}
.search input{
  width: 100%;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--bg-2);
  color: var(--text);
  outline: none;
}
.search input:focus{
  border-color: rgba(34,211,238,.55);
  box-shadow: 0 0 0 4px rgba(34,211,238,.12);
}
.filter-row{
  margin-top: 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}
.filter-actions{ display: flex; align-items: center; gap: 10px; }

.cards-grid{
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  row-gap: 66px;
  column-gap: 12px;
}

.project{
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.project-head{
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}
.project-title{
  margin: 0;
  font-size: 18px;
  letter-spacing: -0.01em;
  line-height: 1.25;
}
.project-meta{ display: flex; gap: 8px; flex-wrap: wrap; }
.badge{
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  font-weight: 800;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .06em;
}
.project p{
  margin: 0;
  color: var(--muted);
  line-height: 1.65;
}
.project-links{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.project-links a{ text-decoration: none !important; }
.project-tech{ display: flex; flex-wrap: wrap; gap: 10px; }

/* =========
   Timeline
   ========= */

.timeline{
  display: grid;
  gap: 12px;
}
.timeline-item{
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 14px;
  align-items: start;
}
.time{
  color: var(--muted);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: .08em;
  font-size: 12px;
  padding-top: 10px;
}
.timeline-item .content h3{
  margin: 0 0 6px;
  letter-spacing: -0.01em;
}
.timeline-item .content p{ margin: 0; color: var(--muted); line-height: 1.65; }

/* =========
   Achievements
   ========= */

.achievement-grid{
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}
.achievement h3{ margin: 0 0 6px; font-size: 16px; }
.achievement p{ margin: 0; color: var(--muted); line-height: 1.6; }

/* =========
   Contact
   ========= */

.contact-grid{
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 12px;
}
.contact-row{
  display: grid;
  grid-template-columns: 80px 1fr auto;
  gap: 10px;
  align-items: center;
  padding: 10px 0;
}
.contact-label{
  color: var(--muted);
  font-weight: 800;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .06em;
}
.divider{
  height: 1px;
  background: var(--border);
  margin: 14px 0;
}

.footer{
  padding: 44px 0 70px;
}

.to-top{
  position: fixed;
  right: 16px;
  bottom: 16px;
  width: 46px;
  height: 46px;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  cursor: pointer;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity .2s ease, transform .2s ease;
}
.to-top.show{
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.to-top:hover{ background: var(--card-2); }

.noscript{
  margin: 18px auto 0;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px dashed var(--border);
  color: var(--muted);
}

/* =========
   Reveal animation
   ========= */

.reveal{
  opacity: 0;
  transform: translateY(10px);
}
.reveal.reveal-visible{
  opacity: 1;
  transform: translateY(0);
  transition: opacity .7s ease, transform .7s ease;
}

@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior: auto; }
  .caret{ animation: none; }
  .reveal{ opacity: 1; transform: none; }
  .reveal.reveal-visible{ transition: none; }
  .btn:hover{ transform: none; }
}

/* =========
   Responsive
   ========= */

@media (max-width: 980px){
  .hero{ grid-template-columns: 1fr; }
  .stats{ grid-template-columns: repeat(3, minmax(0,1fr)); }
  .about-grid{ grid-template-columns: 1fr; }
  .skills-grid{ grid-template-columns: repeat(2, minmax(0,1fr)); }
  .cards-grid{ grid-template-columns: 1fr; }
  .timeline-item{ grid-template-columns: 1fr; }
  .time{ padding-top: 0; }
  .contact-grid{ grid-template-columns: 1fr; }
}

@media (max-width: 560px){
  .nav{ display: none; }
  .stats{ grid-template-columns: 1fr; }
}
.blob-c{
  width: 620px;
  height: 620px;
  left: 15%;
  bottom: -220px;
  background: radial-gradient(circle at 40% 60%, rgba(124,58,237,.55), rgba(124,58,237,0) 70%);
  opacity: .55;
}
.blob-a{ width: 650px; height: 650px; }
.blob-b{ width: 640px; height: 640px; }