/* ══════════════════════════════════════════════════
   SANJAY KUMAR – PORTFOLIO CV
   style.css
══════════════════════════════════════════════════ */

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

:root {
  --clr-bg:       #0d1117;
  --clr-bg2:      #161b22;
  --clr-surface:  #1c2333;
  --clr-border:   #30363d;
  --clr-primary:  #58a6ff;
  --clr-accent:   #3fb950;
  --clr-purple:   #bc8cff;
  --clr-orange:   #f78166;
  --clr-text:     #e6edf3;
  --clr-muted:    #8b949e;
  --clr-hero-grad: linear-gradient(135deg, #0d1117 0%, #161b22 100%);
  --radius:       12px;
  --shadow:       0 8px 32px rgba(0,0,0,.45);
  --transition:   .3s ease;
  --font-main:    'Inter', system-ui, sans-serif;
  --font-mono:    'Fira Code', monospace;
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-main);
  background: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.7;
  overflow-x: hidden;
}

a { color: var(--clr-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: #79c0ff; }

ul { list-style: none; }

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

/* ─── Utility ────────────────────────────────────── */
.container { max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }

.section { padding: 6rem 0; }
.section-alt { background: var(--clr-bg2); }

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  font-weight: 700;
  margin-bottom: 1rem;
  position: relative;
  display: inline-block;
}
.section-title::after {
  content: '';
  position: absolute;
  left: 0; bottom: -6px;
  height: 3px; width: 60%;
  background: linear-gradient(90deg, var(--clr-primary), var(--clr-purple));
  border-radius: 2px;
}
.section-subtitle {
  color: var(--clr-muted);
  margin-bottom: 2.5rem;
  max-width: 640px;
}

/* ─── Buttons ────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  padding: .65rem 1.4rem;
  border-radius: 8px;
  font-size: .9rem; font-weight: 600;
  cursor: pointer;
  border: 2px solid transparent;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}
.btn-primary {
  background: var(--clr-primary);
  color: #0d1117;
}
.btn-primary:hover { background: #79c0ff; color: #0d1117; transform: translateY(-2px); }

.btn-outline {
  border-color: var(--clr-primary);
  color: var(--clr-primary);
  background: transparent;
}
.btn-outline:hover { background: var(--clr-primary); color: #0d1117; transform: translateY(-2px); }

.btn-ghost {
  border-color: var(--clr-border);
  color: var(--clr-text);
  background: transparent;
}
.btn-ghost:hover { border-color: var(--clr-primary); color: var(--clr-primary); }

/* ─── Navbar ─────────────────────────────────────── */
#navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 999;
  background: rgba(13,17,23,.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--clr-border);
  transition: box-shadow var(--transition);
}
#navbar.scrolled { box-shadow: 0 2px 16px rgba(0,0,0,.5); }

.nav-container {
  max-width: 1100px; margin: 0 auto;
  padding: .9rem 1.5rem;
  display: flex; align-items: center; gap: 1.5rem;
}

.nav-logo {
  font-weight: 800; font-size: 1.25rem;
  color: var(--clr-primary);
  letter-spacing: 1px;
}

.nav-links {
  display: flex; gap: .25rem;
  list-style: none;
  margin: 0; padding: 0;
  flex: 1;
}
.nav-links a {
  padding: .4rem .75rem;
  border-radius: 6px;
  font-size: .875rem; font-weight: 500;
  color: var(--clr-muted);
  transition: all var(--transition);
}
.nav-links a:hover,
.nav-links a.active { color: var(--clr-text); background: var(--clr-surface); }

.nav-cta { font-size: .85rem; padding: .5rem 1rem; margin-left: auto; }

.hamburger {
  display: none;
  flex-direction: column; justify-content: center; gap: 5px;
  width: 36px; height: 36px;
  background: none; border: none; cursor: pointer; padding: 4px;
}
.hamburger span {
  display: block; height: 2px; width: 100%;
  background: var(--clr-text);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ─── Hero ───────────────────────────────────────── */
#hero {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  position: relative;
  background: var(--clr-hero-grad);
  overflow: hidden;
  padding-top: 80px;
}

.hero-bg-dots {
  position: absolute; inset: 0;
  background-image: radial-gradient(rgba(88,166,255,.08) 1px, transparent 1px);
  background-size: 30px 30px;
  pointer-events: none;
}

.hero-content {
  position: relative; z-index: 1;
  display: flex; align-items: center; gap: 4rem;
  max-width: 1000px; width: 100%;
  padding: 2rem 1.5rem;
}

.hero-photo-wrap {
  flex-shrink: 0;
  display: flex; flex-direction: column; align-items: center; gap: 1rem;
}
.hero-photo {
  width: 200px; height: 200px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--clr-primary);
  box-shadow: 0 0 40px rgba(88,166,255,.3);
  animation: float 4s ease-in-out infinite;
}
@keyframes float {
  0%,100% { transform: translateY(0); }
  50%      { transform: translateY(-10px); }
}

.hero-badge {
  background: rgba(63,185,80,.15);
  border: 1px solid rgba(63,185,80,.4);
  color: var(--clr-accent);
  font-size: .8rem; font-weight: 600;
  padding: .3rem .8rem; border-radius: 99px;
  display: flex; align-items: center; gap: .4rem;
}

.hero-text { flex: 1; }

.hero-greeting {
  color: var(--clr-muted);
  font-size: 1.05rem; margin-bottom: .25rem;
}
.hero-name {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.1;
  background: linear-gradient(135deg, #e6edf3 30%, var(--clr-primary));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-name-devanagari {
  font-size: 1.1rem; color: var(--clr-muted);
  margin-bottom: .5rem; letter-spacing: .5px;
}
.hero-title-wrap {
  font-family: var(--font-mono);
  font-size: clamp(1rem, 2.5vw, 1.3rem);
  color: var(--clr-primary);
  margin-bottom: .75rem;
  min-height: 2rem;
}
.typed-cursor {
  animation: blink 1s step-start infinite;
}
@keyframes blink { 50% { opacity: 0; } }

.hero-location {
  color: var(--clr-muted);
  font-size: .9rem; margin-bottom: 1.5rem;
  display: flex; align-items: center; gap: .4rem; flex-wrap: wrap;
}
.hero-actions { display: flex; gap: 1rem; flex-wrap: wrap; }

.hero-scroll-down {
  position: absolute; bottom: 2rem; left: 50%; transform: translateX(-50%);
  color: var(--clr-muted); font-size: 1.4rem;
  animation: bounce 2s ease-in-out infinite;
}
@keyframes bounce { 0%,100% { transform: translateX(-50%) translateY(0); } 50% { transform: translateX(-50%) translateY(8px); } }

/* ─── About ──────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 3rem;
  align-items: start;
  margin-top: 2.5rem;
}
.about-text p { color: var(--clr-muted); margin-bottom: 1rem; }
.about-text strong { color: var(--clr-text); }
.about-text a { font-weight: 600; }

.about-highlights {
  display: flex; flex-wrap: wrap; gap: .75rem;
  margin-top: 1.5rem;
}
.highlight-card {
  display: flex; align-items: center; gap: .6rem;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: 8px; padding: .55rem 1rem;
  font-size: .875rem; font-weight: 500;
  color: var(--clr-text);
}
.highlight-card i { color: var(--clr-primary); }

.about-stats {
  display: grid; grid-template-columns: 1fr 1fr; gap: 1rem;
}
.stat-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.5rem 1rem;
  text-align: center;
  transition: transform var(--transition), border-color var(--transition);
}
.stat-card:hover { transform: translateY(-3px); border-color: var(--clr-primary); }
.stat-number { font-size: 2.4rem; font-weight: 800; color: var(--clr-primary); }
.stat-plus { font-size: 1.4rem; font-weight: 700; color: var(--clr-primary); }
.stat-label { display: block; font-size: .8rem; color: var(--clr-muted); margin-top: .25rem; }

/* ─── Skills ─────────────────────────────────────── */
.skills-wrapper {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  margin-top: 2.5rem;
}
.skills-category {
  font-size: 1rem; font-weight: 600;
  color: var(--clr-muted); text-transform: uppercase; letter-spacing: .08em;
  margin-bottom: 1.25rem;
}
.skill-item { margin-bottom: 1.1rem; }
.skill-label {
  display: flex; justify-content: space-between;
  font-size: .9rem; margin-bottom: .4rem;
}
.skill-pct { color: var(--clr-primary); font-weight: 600; }
.skill-bar {
  background: var(--clr-surface);
  border-radius: 99px; height: 8px; overflow: hidden;
}
.skill-fill {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--clr-primary), var(--clr-purple));
  border-radius: 99px;
  transition: width 1.2s cubic-bezier(.4,0,.2,1);
}

.tag-cloud { display: flex; flex-wrap: wrap; gap: .6rem; }
.tag {
  padding: .3rem .75rem; border-radius: 99px;
  font-size: .8rem; font-weight: 500;
  border: 1px solid transparent;
  transition: transform var(--transition);
}
.tag:hover { transform: scale(1.05); }
.tag-primary  { background: rgba(88,166,255,.12);  color: var(--clr-primary);  border-color: rgba(88,166,255,.3); }
.tag-secondary{ background: rgba(188,140,255,.12); color: var(--clr-purple);  border-color: rgba(188,140,255,.3); }
.tag-accent   { background: rgba(63,185,80,.12);   color: var(--clr-accent);  border-color: rgba(63,185,80,.3); }
.tag-neutral  { background: var(--clr-surface);    color: var(--clr-muted);   border-color: var(--clr-border); }
.tag-interest { background: rgba(247,129,102,.1);  color: var(--clr-orange);  border-color: rgba(247,129,102,.3); }

/* ─── Timeline ───────────────────────────────────── */
.timeline { position: relative; margin-top: 2.5rem; }
.timeline::before {
  content: '';
  position: absolute; left: 28px; top: 0; bottom: 0; width: 2px;
  background: linear-gradient(to bottom, var(--clr-primary), var(--clr-purple));
  border-radius: 2px;
}

.timeline-item {
  display: flex; gap: 1.75rem;
  margin-bottom: 2.5rem;
  position: relative;
}
.timeline-dot {
  flex-shrink: 0;
  width: 58px; height: 58px;
  background: var(--clr-primary);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem; color: #0d1117;
  border: 3px solid var(--clr-bg);
  z-index: 1;
}
.timeline-dot.edu { background: var(--clr-purple); }

.timeline-card {
  flex: 1;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: border-color var(--transition), transform var(--transition);
}
.timeline-card:hover { border-color: var(--clr-primary); transform: translateX(4px); }

.timeline-header {
  display: flex; justify-content: space-between; align-items: flex-start;
  flex-wrap: wrap; gap: .5rem;
  margin-bottom: .75rem;
}
.timeline-header h3 { font-size: 1.15rem; font-weight: 700; }
.timeline-org { color: var(--clr-muted); font-size: .9rem; margin-top: .2rem; }
.timeline-date {
  background: rgba(88,166,255,.1);
  color: var(--clr-primary);
  font-size: .8rem; font-weight: 600;
  padding: .25rem .75rem; border-radius: 99px;
  white-space: nowrap;
}

.timeline-bullets { padding-left: 1.25rem; list-style: disc; margin-top: .5rem; }
.timeline-bullets li { color: var(--clr-muted); margin-bottom: .4rem; font-size: .9rem; }

.timeline-tags { display: flex; flex-wrap: wrap; gap: .5rem; margin-top: 1rem; }
.timeline-tags span {
  background: var(--clr-bg2);
  border: 1px solid var(--clr-border);
  color: var(--clr-muted);
  font-size: .78rem; padding: .2rem .6rem; border-radius: 6px;
}

/* ─── Publications ───────────────────────────────── */
.pub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}
.pub-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.pub-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--clr-primary); }
.pub-type {
  display: inline-flex; align-items: center; gap: .4rem;
  font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em;
  margin-bottom: .75rem; padding: .25rem .65rem; border-radius: 6px;
}
.pub-type.paper { background: rgba(88,166,255,.12); color: var(--clr-primary); }
.pub-type.patent { background: rgba(247,129,102,.12); color: var(--clr-orange); }
.pub-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: .65rem; line-height: 1.4; }
.pub-card p { font-size: .875rem; color: var(--clr-muted); margin-bottom: 1rem; }
.pub-tags { display: flex; flex-wrap: wrap; gap: .5rem; }
.pub-tags span {
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  color: var(--clr-muted);
  font-size: .75rem; padding: .2rem .55rem; border-radius: 6px;
}

/* ─── Projects ───────────────────────────────────── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 2.5rem;
}
.project-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  display: flex; flex-direction: column;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.project-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--clr-primary); }
.project-card-cta {
  align-items: center; justify-content: center; gap: 1rem;
  text-align: center; color: var(--clr-muted);
  border-style: dashed;
}

.project-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: .75rem; }
.project-icon { font-size: 1.5rem; color: var(--clr-muted); }
.project-stars { display: flex; align-items: center; gap: .3rem; color: #e3b341; font-size: .85rem; }
.project-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: .5rem; }
.project-card h3 a { color: var(--clr-text); }
.project-card h3 a:hover { color: var(--clr-primary); }
.project-card p { font-size: .875rem; color: var(--clr-muted); flex: 1; margin-bottom: 1rem; }
.project-footer { font-size: .8rem; color: var(--clr-muted); display: flex; align-items: center; gap: .5rem; }
.lang-dot {
  width: 12px; height: 12px; border-radius: 50%; display: inline-block;
}
.lang-dot.cpp     { background: #f34b7d; }
.lang-dot.js      { background: #f1e05a; }
.lang-dot.py      { background: #3572A5; }
.lang-dot.neutral { background: var(--clr-muted); }

/* ─── Hobbies ────────────────────────────────────── */
.hobbies-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}
.hobby-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: flex;
  gap: 1.25rem;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.hobby-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--clr-primary); }

.hobby-icon {
  flex-shrink: 0;
  width: 52px; height: 52px;
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem;
}
.hobby-body { flex: 1; }
.hobby-body h3 { font-size: 1rem; font-weight: 700; margin-bottom: .5rem; }
.hobby-body p { font-size: .875rem; color: var(--clr-muted); margin-bottom: .75rem; }
.hobby-link {
  display: inline-flex; align-items: center; gap: .4rem;
  font-size: .82rem; font-weight: 600;
  color: var(--clr-primary);
}
.hobby-link:hover { text-decoration: underline; }

.hobby-tags { display: flex; flex-wrap: wrap; gap: .4rem; margin-bottom: .75rem; }
.hobby-tags span {
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  color: var(--clr-muted);
  font-size: .75rem; padding: .2rem .55rem; border-radius: 6px;
}

.games-list {
  display: flex; flex-wrap: wrap; gap: .4rem .75rem;
  margin-bottom: .75rem;
}
.games-list span {
  font-size: .8rem; color: var(--clr-muted);
  display: flex; align-items: center; gap: .3rem;
}
.games-list i { font-size: .45rem; color: var(--clr-primary); }

/* ─── Contact ────────────────────────────────────── */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin-top: 2.5rem;
}
.contact-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: flex; align-items: center; gap: 1rem;
  color: var(--clr-text);
  transition: all var(--transition);
  text-decoration: none;
}
.contact-card:hover {
  border-color: var(--clr-primary);
  transform: translateY(-3px);
  box-shadow: var(--shadow);
  color: var(--clr-text);
}
.contact-card i { font-size: 1.8rem; color: var(--clr-primary); }
.contact-card strong { display: block; font-weight: 600; }
.contact-card span { font-size: .85rem; color: var(--clr-muted); }

/* ─── Footer ─────────────────────────────────────── */
#footer {
  background: var(--clr-bg2);
  border-top: 1px solid var(--clr-border);
  padding: 2rem 0;
  text-align: center;
}
.footer-inner p { color: var(--clr-muted); font-size: .9rem; }
.footer-inner a { color: var(--clr-primary); }
.footer-sub { margin-top: .35rem; font-size: .8rem; }

/* ─── Back to top ────────────────────────────────── */
#back-to-top {
  position: fixed; bottom: 1.75rem; right: 1.75rem; z-index: 990;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--clr-primary); color: #0d1117;
  border: none; cursor: pointer; font-size: 1rem;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 4px 14px rgba(88,166,255,.4);
  opacity: 0; transform: translateY(20px);
  transition: opacity var(--transition), transform var(--transition);
}
#back-to-top.visible { opacity: 1; transform: translateY(0); }
#back-to-top:hover { background: #79c0ff; transform: translateY(-2px); }

/* ─── Reveal animation ───────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity .6s ease, transform .6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ─── Responsive ─────────────────────────────────── */
@media (max-width: 900px) {
  .hero-content { flex-direction: column; text-align: center; gap: 2rem; }
  .hero-location { justify-content: center; }
  .hero-actions { justify-content: center; }
  .about-grid { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: repeat(4, 1fr); }
  .skills-wrapper { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav-links { 
    display: none; flex-direction: column; 
    position: absolute; top: 100%; left: 0; right: 0;
    background: rgba(13,17,23,.97);
    border-bottom: 1px solid var(--clr-border);
    padding: 1rem;
    gap: .25rem;
  }
  .nav-links.open { display: flex; }
  .nav-cta { display: none; }
  .hamburger { display: flex; margin-left: auto; }
  .about-stats { grid-template-columns: repeat(2, 1fr); }
  .timeline::before { left: 22px; }
  .timeline-dot { width: 46px; height: 46px; font-size: 1rem; }
}

@media (max-width: 480px) {
  .section { padding: 4rem 0; }
  .hero-photo { width: 150px; height: 150px; }
  .projects-grid { grid-template-columns: 1fr; }
}