/* ── RESET & VARIABLES ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0a0f1e;
  --bg2: #0d1529;
  --bg3: #111b35;
  --card: #131e38;
  --border: #1e2d50;
  --accent: #38bdf8;
  --accent2: #818cf8;
  --accent3: #34d399;
  --text: #e2e8f0;
  --muted: #64748b;
  --muted2: #94a3b8;
  --white: #f8fafc;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

/* ── SCROLLBAR ── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ── NAV ── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem 2rem;
  background: rgba(10, 15, 30, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(56, 189, 248, 0.08);
  transition: all 0.3s;
}
nav.scrolled { border-bottom-color: var(--border); }

.nav-logo {
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  letter-spacing: -0.5px;
}
.nav-logo span { color: var(--muted2); }

.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a {
  color: var(--muted2); text-decoration: none; font-size: 0.875rem;
  font-weight: 500; letter-spacing: 0.02em;
  transition: color 0.2s;
  position: relative;
}
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0; right: 0;
  height: 1px; background: var(--accent);
  transform: scaleX(0); transform-origin: right;
  transition: transform 0.3s;
}
.nav-links a:hover { color: var(--accent); }
.nav-links a:hover::after { transform: scaleX(1); transform-origin: left; }
.nav-links a.active { color: var(--accent); }
.nav-links a.active::after { transform: scaleX(1); transform-origin: left; }


/* Theme Toggle */
.theme-toggle {
  height: 36px;
  padding: 0 0.85rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--muted2);
  font-size: 0.8rem; font-weight: 500;
  cursor: pointer;
  display: flex; align-items: center; gap: 0.4rem;
  transition: all 0.2s;
  flex-shrink: 0;
  letter-spacing: 0.03em;
}
.theme-toggle:hover {
  border-color: var(--accent);
  background: rgba(56,189,248,0.08);
  color: var(--accent);
}

/* Hamburger */
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 4px; }
.hamburger span { width: 24px; height: 2px; background: var(--muted2); border-radius: 2px; transition: all 0.3s; }

/* ── HERO ── */
#hero {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  position: relative; overflow: hidden;
  padding: 6rem 2rem 4rem;
}
#hero-canvas { position: absolute; inset: 0; z-index: 0; }

.hero-content {
  position: relative; z-index: 1;
  max-width: 800px; text-align: center;
}

.hero-badge {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.4rem 1rem;
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: 100px;
  font-size: 0.8rem; font-weight: 500; color: var(--accent);
  font-family: 'JetBrains Mono', monospace;
  margin-bottom: 1.5rem;
  letter-spacing: 0.05em;
}
.hero-badge::before { content: '●'; font-size: 0.5rem; animation: blink 1.5s infinite; }

@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

.hero-name {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  letter-spacing: -2px;
  line-height: 1.05;
  color: var(--white);
  margin-bottom: 0.75rem;
}
.hero-name .accent { color: var(--accent); }

.hero-title {
  font-size: clamp(1rem, 2.5vw, 1.35rem);
  color: var(--muted2);
  font-weight: 400;
  margin-bottom: 1.5rem;
}
.hero-title strong { color: var(--accent2); font-weight: 600; }

.hero-desc {
  font-size: 1rem; color: var(--muted2);
  max-width: 580px; margin: 0 auto 2.5rem;
  line-height: 1.8;
}

.hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

.btn {
  padding: 0.75rem 1.75rem;
  border-radius: 8px;
  font-size: 0.9rem; font-weight: 600;
  text-decoration: none;
  display: inline-flex; align-items: center; gap: 0.5rem;
  transition: all 0.2s;
  cursor: pointer; border: none;
}
.btn-primary { background: var(--accent); color: var(--bg); }
.btn-primary:hover { background: #7dd3fc; transform: translateY(-2px); box-shadow: 0 8px 24px rgba(56,189,248,0.3); }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--accent2); color: var(--accent2); transform: translateY(-2px); }

.hero-stats {
  display: flex; justify-content: center; gap: 3rem;
  margin-top: 4rem; flex-wrap: wrap;
}
.stat { text-align: center; }
.stat-num {
  font-size: 2rem; font-weight: 800; color: var(--white);
  font-family: 'JetBrains Mono', monospace;
  line-height: 1;
}
.stat-num .accent { color: var(--accent); }
.stat-label { font-size: 0.75rem; color: var(--muted); margin-top: 0.25rem; letter-spacing: 0.08em; text-transform: uppercase; }

/* ── SECTIONS ── */
section { padding: 6rem 2rem; }
.container { max-width: 1000px; margin: 0 auto; }

.section-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem; font-weight: 500;
  color: var(--accent); letter-spacing: 0.15em;
  text-transform: uppercase; margin-bottom: 0.75rem;
}
.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 800; letter-spacing: -1px;
  color: var(--white); margin-bottom: 3rem;
  line-height: 1.1;
}
.section-title span { color: var(--accent); }

/* ── SKILLS ── */
#skills { background: var(--bg2); }

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

.skill-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  transition: all 0.3s;
  position: relative;
  overflow: hidden;
}
.skill-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.4s;
}
.skill-card:hover { border-color: rgba(56,189,248,0.3); transform: translateY(-3px); }
.skill-card:hover::before { transform: scaleX(1); }

.skill-card-icon { font-size: 1.75rem; margin-bottom: 0.75rem; }
.skill-card-title {
  font-size: 0.8rem; font-weight: 600; color: var(--accent);
  letter-spacing: 0.1em; text-transform: uppercase;
  font-family: 'JetBrains Mono', monospace;
  margin-bottom: 0.75rem;
}

.skill-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.tag {
  padding: 0.3rem 0.75rem;
  background: rgba(56,189,248,0.08);
  border: 1px solid rgba(56,189,248,0.15);
  border-radius: 100px;
  font-size: 0.78rem; font-weight: 500;
  color: var(--muted2);
  transition: all 0.2s;
}
.tag:hover { background: rgba(56,189,248,0.15); color: var(--accent); border-color: rgba(56,189,248,0.4); }

/* ── SKILL PROFICIENCY ── */
.skill-level {
  display: flex; align-items: center; gap: 5px;
  margin-top: 1rem; padding-top: 0.75rem;
  border-top: 1px solid var(--border);
}
.dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--border);
  flex-shrink: 0;
}
.dot.filled { background: var(--accent); box-shadow: 0 0 4px rgba(56,189,248,0.5); }
.skill-level-label {
  font-size: 0.68rem; color: var(--muted2);
  font-family: 'JetBrains Mono', monospace;
  margin-left: auto; letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* ── EXPERIENCE ── */
#experience { background: var(--bg); }

.timeline { position: relative; padding-left: 2rem; }
.timeline::before {
  content: '';
  position: absolute; left: 0; top: 0; bottom: 0; width: 1px;
  background: linear-gradient(to bottom, var(--accent), var(--accent2), transparent);
}

.timeline-item {
  position: relative; margin-bottom: 3rem;
  opacity: 0; transform: translateX(-20px);
  transition: opacity 0.6s, transform 0.6s;
}
.timeline-item.visible { opacity: 1; transform: translateX(0); }

.timeline-dot {
  position: absolute; left: -2.35rem; top: 0.25rem;
  width: 12px; height: 12px;
  background: var(--accent); border-radius: 50%;
  border: 2px solid var(--bg);
  box-shadow: 0 0 0 3px rgba(56,189,248,0.2);
}

.exp-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.75rem;
  transition: border-color 0.3s;
}
.exp-card:hover { border-color: rgba(56,189,248,0.3); }

.exp-header {
  display: flex; justify-content: space-between;
  align-items: flex-start; flex-wrap: wrap;
  gap: 0.5rem; margin-bottom: 0.25rem;
}
.exp-company { font-size: 1.1rem; font-weight: 700; color: var(--white); }
.exp-period {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem; color: var(--accent); font-weight: 500;
  background: rgba(56,189,248,0.1); border: 1px solid rgba(56,189,248,0.2);
  padding: 0.25rem 0.75rem; border-radius: 100px;
  white-space: nowrap;
}
.exp-role { font-size: 0.9rem; color: var(--accent2); font-weight: 600; margin-bottom: 1rem; }

.exp-badge {
  display: inline-block;
  font-size: 0.7rem; font-weight: 600;
  padding: 0.15rem 0.6rem; border-radius: 4px;
  margin-left: 0.5rem; vertical-align: middle;
}
.badge-fulltime { background: rgba(52,211,153,0.15); color: var(--accent3); border: 1px solid rgba(52,211,153,0.3); }
.badge-intern   { background: rgba(129,140,248,0.15); color: var(--accent2); border: 1px solid rgba(129,140,248,0.3); }

.exp-list { list-style: none; padding: 0; }
.exp-list li {
  position: relative; padding-left: 1.25rem;
  margin-bottom: 0.6rem; font-size: 0.9rem; color: var(--muted2); line-height: 1.7;
}
.exp-list li::before { content: '▸'; position: absolute; left: 0; color: var(--accent); font-size: 0.75rem; top: 0.15rem; }
.exp-list li strong { color: var(--text); }

.exp-impact {
  display: inline-flex; align-items: center; gap: 0.35rem;
  background: rgba(52,211,153,0.1); border: 1px solid rgba(52,211,153,0.2);
  color: var(--accent3); font-size: 0.78rem; font-weight: 600;
  padding: 0.15rem 0.6rem; border-radius: 100px;
  font-family: 'JetBrains Mono', monospace;
}

.exp-divider { border: none; border-top: 1px solid var(--border); margin: 1.25rem 0; }

/* ── EDUCATION ── */
#education { background: var(--bg2); }

.edu-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem;
  display: flex; gap: 1.5rem; align-items: flex-start;
  transition: border-color 0.3s;
}
.edu-card:hover { border-color: rgba(129,140,248,0.4); }

.edu-icon {
  font-size: 2.5rem; flex-shrink: 0;
  width: 56px; height: 56px;
  display: flex; align-items: center; justify-content: center;
  background: rgba(129,140,248,0.1); border-radius: 12px;
}
.edu-year {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem; color: var(--accent2);
  margin-bottom: 0.25rem; font-weight: 500;
}
.edu-institution { font-size: 1.15rem; font-weight: 700; color: var(--white); margin-bottom: 0.25rem; }
.edu-degree { font-size: 0.9rem; color: var(--muted2); margin-bottom: 1rem; }

.cgpa-grid { display: flex; gap: 1rem; flex-wrap: wrap; }
.cgpa-item {
  background: rgba(56,189,248,0.08); border: 1px solid rgba(56,189,248,0.15);
  border-radius: 8px; padding: 0.5rem 1rem; text-align: center;
}
.cgpa-val { font-family: 'JetBrains Mono', monospace; font-size: 1.1rem; font-weight: 700; color: var(--accent); }
.cgpa-lbl { font-size: 0.7rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; }

/* ── PUBLICATIONS ── */
#publications { background: var(--bg); }

.pub-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px; padding: 2rem;
  transition: border-color 0.3s, transform 0.3s;
  position: relative; overflow: hidden;
}
.pub-card::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(56,189,248,0.04), rgba(129,140,248,0.04));
  pointer-events: none;
}
.pub-card:hover { border-color: rgba(129,140,248,0.4); transform: translateY(-3px); }

.pub-journal {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.72rem; color: var(--accent2);
  text-transform: uppercase; letter-spacing: 0.12em;
  margin-bottom: 0.75rem; font-weight: 600;
}
.pub-title { font-size: 1.1rem; font-weight: 700; color: var(--white); margin-bottom: 0.75rem; line-height: 1.4; }
.pub-meta { display: flex; gap: 1rem; flex-wrap: wrap; margin-bottom: 1.25rem; }
.pub-meta-item { display: flex; align-items: center; gap: 0.35rem; font-size: 0.8rem; color: var(--muted2); }

.pub-details { list-style: none; margin-bottom: 1.25rem; }
.pub-details li {
  position: relative; padding-left: 1.25rem;
  margin-bottom: 0.4rem; font-size: 0.875rem; color: var(--muted2);
}
.pub-details li::before { content: '▸'; position: absolute; left: 0; color: var(--accent2); font-size: 0.7rem; top: 0.2rem; }

.pub-metrics { display: flex; gap: 1rem; flex-wrap: wrap; }
.metric {
  display: flex; flex-direction: column; align-items: center;
  background: rgba(56,189,248,0.06); border: 1px solid rgba(56,189,248,0.12);
  border-radius: 8px; padding: 0.6rem 1rem;
}
.metric-val { font-family: 'JetBrains Mono', monospace; font-size: 1rem; font-weight: 700; color: var(--accent3); }
.metric-lbl { font-size: 0.7rem; color: var(--muted); letter-spacing: 0.06em; }

/* ── PROJECTS ── */
#projects { background: var(--bg2); }

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
  gap: 1.25rem;
}

.project-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  display: flex; flex-direction: column; gap: 0.75rem;
  transition: all 0.3s;
  position: relative; overflow: hidden;
}
.project-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--accent2), var(--accent));
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.4s;
}
.project-card:hover { border-color: rgba(129,140,248,0.35); transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,0,0,0.2); }
.project-card:hover::before { transform: scaleX(1); }

.project-header {
  display: flex; justify-content: space-between; align-items: center;
}
.project-icon { font-size: 1.75rem; }
.project-link {
  font-size: 0.78rem; font-weight: 600;
  color: var(--accent2); text-decoration: none;
  font-family: 'JetBrains Mono', monospace;
  border: 1px solid rgba(129,140,248,0.25);
  padding: 0.25rem 0.65rem; border-radius: 6px;
  transition: all 0.2s;
}
.project-link:hover { background: rgba(129,140,248,0.1); border-color: var(--accent2); }

.project-title {
  font-size: 1rem; font-weight: 700; color: var(--white);
  line-height: 1.3;
}
.project-desc {
  font-size: 0.85rem; color: var(--muted2); line-height: 1.7; flex: 1;
}
.project-footer {
  display: flex; justify-content: space-between; align-items: center;
  padding-top: 0.75rem; border-top: 1px solid var(--border);
  margin-top: auto;
}
.project-stars { font-size: 0.78rem; color: var(--accent3); font-weight: 600; font-family: 'JetBrains Mono', monospace; }
.project-lang  { font-size: 0.72rem; color: var(--muted); font-family: 'JetBrains Mono', monospace; }

/* ── CONTACT ── */
#contact { background: var(--bg2); }

.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
.contact-info { display: flex; flex-direction: column; gap: 1rem; }

.contact-item {
  display: flex; align-items: center; gap: 1rem;
  background: var(--card); border: 1px solid var(--border);
  border-radius: 10px; padding: 1rem 1.25rem;
  text-decoration: none; color: inherit;
  transition: all 0.2s;
}
.contact-item:hover { border-color: var(--accent); transform: translateX(4px); }

.contact-item-icon {
  width: 40px; height: 40px; border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem; flex-shrink: 0;
}
.ci-mail     { background: rgba(56,189,248,0.12); }
.ci-phone    { background: rgba(52,211,153,0.12); }
.ci-location { background: rgba(251,191,36,0.12); }
.ci-linkedin { background: rgba(129,140,248,0.12); }
.ci-github   { background: rgba(248,248,248,0.08); }
.ci-scholar  { background: rgba(52,211,153,0.12); }

.contact-item-label { font-size: 0.7rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.15rem; }
.contact-item-val   { font-size: 0.9rem; color: var(--text); font-weight: 500; }

.contact-cta {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 12px; padding: 2rem;
  display: flex; flex-direction: column; justify-content: center; align-items: flex-start; gap: 1rem;
}
.contact-cta-title { font-size: 1.35rem; font-weight: 700; color: var(--white); line-height: 1.3; }
.contact-cta-desc  { font-size: 0.9rem; color: var(--muted2); line-height: 1.7; }

/* ── FOOTER ── */
footer {
  text-align: center; padding: 2rem;
  border-top: 1px solid var(--border);
  font-size: 0.8rem; color: var(--muted);
  font-family: 'JetBrains Mono', monospace;
}
footer span { color: var(--accent2); }

/* ── FADE-IN ANIMATION ── */
.fade-in {
  opacity: 0; transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .nav-links { display: none; flex-direction: column; gap: 1rem; }
  .nav-links.open {
    display: flex; position: absolute; top: 100%; left: 0; right: 0;
    background: var(--bg2); border-bottom: 1px solid var(--border);
    padding: 1.5rem 2rem;
  }
  .hamburger   { display: flex; }
  .hero-stats  { gap: 2rem; }
  .contact-grid { grid-template-columns: 1fr; }
  .edu-card    { flex-direction: column; }
  .timeline    { padding-left: 1.5rem; }
  .timeline-dot { left: -1.85rem; }
}

/* ── CONTACT FORM ── */
.contact-form {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 12px; padding: 2rem;
  display: flex; flex-direction: column; gap: 1rem;
}
.form-group { display: flex; flex-direction: column; gap: 0.4rem; }
.form-label {
  font-size: 0.72rem; font-weight: 600; color: var(--muted2);
  text-transform: uppercase; letter-spacing: 0.08em;
  font-family: 'JetBrains Mono', monospace;
}
.form-input {
  background: var(--bg); border: 1px solid var(--border);
  border-radius: 8px; padding: 0.65rem 1rem;
  color: var(--text); font-size: 0.9rem; font-family: 'Inter', sans-serif;
  transition: border-color 0.2s; outline: none; width: 100%;
}
.form-input:focus { border-color: var(--accent); }
.form-input::placeholder { color: var(--muted); }
.form-textarea { resize: vertical; min-height: 110px; }

/* ── SCROLL PROGRESS BAR ── */
#scroll-progress {
  position: fixed; top: 0; left: 0; z-index: 200;
  height: 3px; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  transition: width 0.08s linear;
  pointer-events: none;
}

/* ── BACK TO TOP ── */
#back-to-top {
  position: fixed; bottom: 2rem; right: 2rem; z-index: 300;
  width: 42px; height: 42px;
  background: var(--card); border: 1px solid var(--border);
  color: var(--accent); border-radius: 8px;
  font-size: 1.1rem; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; pointer-events: none;
  transition: all 0.3s;
  font-family: 'JetBrains Mono', monospace;
}
#back-to-top.visible { opacity: 1; pointer-events: auto; }
#back-to-top:hover { background: var(--accent); color: var(--bg); border-color: var(--accent); transform: translateY(-3px); }

/* ── TOAST ── */
#toast {
  position: fixed; bottom: 5rem; left: 50%;
  transform: translateX(-50%) translateY(12px);
  background: var(--card); border: 1px solid var(--accent);
  color: var(--text); padding: 0.6rem 1.25rem;
  border-radius: 8px; font-size: 0.82rem;
  opacity: 0; pointer-events: none;
  transition: opacity 0.3s, transform 0.3s;
  z-index: 500; white-space: nowrap;
  font-family: 'JetBrains Mono', monospace;
}
#toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ── LIGHT MODE ── */
body.light {
  --bg: #f4f6fa;
  --bg2: #edf0f7;
  --bg3: #e2e7f2;
  --card: #fafbfd;
  --border: #d4dbe8;
  --text: #3d5069;
  --muted: #8096ac;
  --muted2: #5a7490;
  --white: #1e3148;
  --accent: #2a9fd4;
  --accent2: #6d78e0;
  --accent3: #25b87a;
}
body.light nav { background: rgba(244, 246, 250, 0.92); }
body.light #hero-canvas { opacity: 0.18; }