/* ═══════════════════════════════════════════════════════════════════
   AI ENGINEER PORTFOLIO — STYLES.CSS
   Premium Dark Mode | Glassmorphism | Neon Glow
═══════════════════════════════════════════════════════════════════ */

/* ─── CSS CUSTOM PROPERTIES ─── */
:root {
  --bg-primary: #050510;
  --bg-secondary: #0a0a1a;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-card-hover: rgba(255, 255, 255, 0.07);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(0, 212, 255, 0.3);

  --accent-cyan: #00d4ff;
  --accent-violet: #7c3aed;
  --accent-blue: #3b82f6;
  --accent-pink: #f472b6;
  --accent-green: #10b981;

  --text-primary: #f0f0ff;
  --text-secondary: rgba(240, 240, 255, 0.65);
  --text-muted: rgba(240, 240, 255, 0.4);

  --gradient-main: linear-gradient(135deg, #00d4ff, #7c3aed);
  --gradient-subtle: linear-gradient(135deg, rgba(0,212,255,0.1), rgba(124,58,237,0.1));

  --font-heading: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --radius: 16px;
  --radius-sm: 8px;
  --radius-lg: 24px;
  --shadow-card: 0 4px 32px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 40px rgba(0, 212, 255, 0.15);

  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

::selection { background: rgba(0,212,255,0.25); color: var(--text-primary); }
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--accent-cyan); border-radius: 2px; }

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
button { cursor: pointer; border: none; background: none; }
ul { list-style: none; }

/* ─── UTILITIES ─── */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

.text-gradient {
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ─── PRELOADER ─── */
#preloader {
  position: fixed; inset: 0;
  background: var(--bg-primary);
  display: flex; align-items: center; justify-content: center;
  z-index: 9999;
  transition: opacity 0.6s ease, visibility 0.6s ease;
}
#preloader.fade-out { opacity: 0; visibility: hidden; }

.preloader-inner { text-align: center; }

.ai-logo {
  font-family: var(--font-heading);
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 24px;
  animation: pulse 1.5s ease-in-out infinite;
}
.ai-logo .logo-bracket { color: var(--accent-cyan); }
.ai-logo .logo-text { color: var(--text-primary); margin: 0 2px; }

.preloader-bar {
  width: 200px; height: 2px;
  background: rgba(255,255,255,0.1);
  border-radius: 2px;
  margin: 0 auto 12px;
  overflow: hidden;
}
.preloader-fill {
  height: 100%;
  background: var(--gradient-main);
  border-radius: 2px;
  animation: loadBar 2s ease-in-out forwards;
}
.preloader-label { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); }

@keyframes loadBar { 0% { width: 0; } 100% { width: 100%; } }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.6; } }

/* ─── NAVBAR ─── */
#navbar {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 1000;
  transition: var(--transition);
  padding: 16px 0;
}
#navbar.scrolled {
  background: rgba(5, 5, 16, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  padding: 10px 0;
  box-shadow: 0 4px 24px rgba(0,0,0,0.4);
}

.nav-container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 40px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
  flex-shrink: 0;
}
.nav-logo .logo-bracket { color: var(--accent-cyan); }
.nav-logo .logo-text { 
  font-family: var(--font-heading); 
  font-size: 1.6rem; 
  font-weight: 700; 
  letter-spacing: -0.5px; 
  background: linear-gradient(135deg, #fff 30%, var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  transition: var(--transition); 
}
.nav-logo:hover .logo-text { filter: drop-shadow(0 0 10px rgba(0,212,255,0.6)); }

.logo-icon {
  font-size: 1.8rem;
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: heartbeat 2s ease-in-out infinite;
  transition: var(--transition);
  filter: drop-shadow(0 0 8px rgba(124, 58, 237, 0.4));
}
.nav-logo:hover .logo-icon {
  filter: drop-shadow(0 0 15px rgba(0, 212, 255, 0.6));
  transform: translateY(-2px);
}

@keyframes heartbeat {
  0%, 100% { transform: scale(1); }
  15% { transform: scale(1.15); }
  30% { transform: scale(1); }
  45% { transform: scale(1.15); }
  60% { transform: scale(1); }
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}
.nav-link {
  padding: 8px 14px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: var(--transition);
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute; bottom: 4px; left: 50%; transform: translateX(-50%);
  width: 0; height: 2px;
  background: var(--gradient-main);
  border-radius: 1px;
  transition: var(--transition);
}
.nav-link:hover { color: var(--text-primary); }
.nav-link:hover::after, .nav-link.active::after { width: 20px; }
.nav-link.active { color: var(--accent-cyan); }

.nav-cta {
  padding: 10px 22px;
  background: var(--gradient-main);
  color: #fff;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  transition: var(--transition);
  white-space: nowrap;
  flex-shrink: 0;
  box-shadow: 0 0 20px rgba(0,212,255,0.25);
}
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 0 32px rgba(0,212,255,0.45); }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
  margin-left: auto;
}
.hamburger span {
  display: block; width: 22px; height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: var(--transition);
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ─── BUTTONS ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  font-family: var(--font-body);
  transition: var(--transition);
  cursor: pointer;
}
.btn-primary {
  background: var(--gradient-main);
  color: #fff;
  box-shadow: 0 0 24px rgba(0,212,255,0.2);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 0 40px rgba(0,212,255,0.4); }
.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
}
.btn-secondary:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); transform: translateY(-2px); }
.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}
.btn-ghost:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); }
.btn-full { width: 100%; justify-content: center; }

/* ─── HERO SECTION ─── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 80px 0 40px;
  position: relative;
  overflow: hidden;
  background: radial-gradient(ellipse 80% 80% at 50% -20%, rgba(0,212,255,0.08), transparent),
              radial-gradient(ellipse 60% 60% at 80% 50%, rgba(124,58,237,0.08), transparent);
}

#particleCanvas {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  max-width: 1240px;
  margin: 0 auto;
  width: 100%;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr 400px;
  align-items: center;
  gap: 80px;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  border-radius: 50px;
  font-size: 0.8rem;
  color: var(--accent-green);
  font-weight: 500;
  margin-bottom: 20px;
  width: fit-content;
}
.badge-dot {
  width: 8px; height: 8px;
  background: var(--accent-green);
  border-radius: 50%;
  animation: blink 1.5s ease-in-out infinite;
}
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0.3; } }

.hero-title {
  display: flex;
  flex-direction: column;
  margin-bottom: 16px;
}
.hero-greeting {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 2px;
  text-transform: uppercase;
}
.hero-name {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 4vw, 3.5rem);
  font-weight: 700;
  line-height: 1.1;
  background: linear-gradient(135deg, #fff 30%, var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -2px;
}

.hero-role {
  font-family: var(--font-heading);
  font-size: clamp(1.2rem, 2.5vw, 1.6rem);
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 20px;
  min-height: 2em;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 4px;
}
.role-prefix { color: var(--text-secondary); }
#typewriter { color: var(--accent-cyan); font-weight: 600; }
.cursor {
  color: var(--accent-cyan);
  animation: blink 0.8s infinite;
  font-weight: 300;
}

.hero-description {
  max-width: 520px;
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 32px;
  line-height: 1.8;
}
.hero-description strong { color: var(--accent-cyan); font-weight: 600; }

.hero-stats {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}
.stat-item { text-align: center; }
.stat-number {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  background: var(--gradient-main);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}
.stat-plus { font-size: 1.2rem; font-weight: 700; color: var(--accent-cyan); }
.stat-label { display: block; font-size: 0.75rem; color: var(--text-muted); margin-top: 4px; text-transform: uppercase; letter-spacing: 1px; }
.stat-divider { width: 1px; height: 40px; background: var(--border-color); }

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 32px; }

.hero-social { display: flex; align-items: center; gap: 12px; }
.social-icon {
  width: 42px; height: 42px;
  display: flex; align-items: center; justify-content: center;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 50%;
  color: var(--text-secondary);
  font-size: 1rem;
  transition: var(--transition);
}
.social-icon:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(0,212,255,0.2);
}

.hero-image-container {
  position: relative;
  width: 380px;
  height: 380px;
  flex-shrink: 0;
}
.hero-image-glow {
  position: absolute;
  inset: -20px;
  background: radial-gradient(circle, rgba(0,212,255,0.2), rgba(124,58,237,0.15), transparent 70%);
  border-radius: 50%;
  animation: rotateGlow 8s linear infinite;
}
@keyframes rotateGlow { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }

.hero-image-ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid;
  animation: ringPulse 3s ease-in-out infinite;
}
.ring-1 { inset: -8px; border-color: rgba(0,212,255,0.4); animation-delay: 0s; }
.ring-2 { inset: -20px; border-color: rgba(124,58,237,0.25); animation-delay: 0.5s; }
.ring-3 { inset: -35px; border-color: rgba(0,212,255,0.1); animation-delay: 1s; }

@keyframes ringPulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.03); opacity: 0.6; }
}

.hero-photo {
  width: 100%; height: 100%;
  object-fit: cover;
  border-radius: 50%;
  border: 3px solid rgba(0,212,255,0.3);
  position: relative;
  z-index: 2;
}

.floating-badge {
  display: none !important;
  position: absolute;
  background: rgba(10, 10, 26, 0.9);
  border: 1px solid var(--border-glow);
  border-radius: 50px;
  padding: 6px 14px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-cyan);
  backdrop-filter: blur(10px);
  z-index: 3;
  animation: float 4s ease-in-out infinite;
}
.badge-pytorch { top: 10%; right: -20px; animation-delay: 0s; }
.badge-llm { bottom: 25%; right: -30px; animation-delay: 1.2s; }
.badge-cv { top: 30%; left: -25px; animation-delay: 0.6s; }

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-8px); }
}

.hero-text { display: flex; flex-direction: column; align-items: flex-start; }

.scroll-indicator {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.75rem;
  z-index: 2;
  animation: bounce 2s ease-in-out infinite;
}
.scroll-mouse {
  width: 24px; height: 38px;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  display: flex;
  justify-content: center;
  padding-top: 6px;
}
.scroll-wheel {
  width: 4px; height: 8px;
  background: var(--accent-cyan);
  border-radius: 2px;
  animation: scrollWheel 2s ease-in-out infinite;
}
@keyframes scrollWheel { 0% { transform: translateY(0); opacity: 1; } 100% { transform: translateY(12px); opacity: 0; } }
@keyframes bounce { 0%, 100% { transform: translateX(-50%) translateY(0); } 50% { transform: translateX(-50%) translateY(-5px); } }

/* ─── SECTION COMMON STYLES ─── */
.section { padding: 50px 0; position: relative; }
.section-header { text-align: center; margin-bottom: 40px; }
.section-tag {
  font-family: var(--font-mono); font-size: 0.85rem; color: var(--accent-cyan);
  letter-spacing: 1px; margin-bottom: 12px; display: block;
}
.section-title {
  font-family: var(--font-heading); font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 700; letter-spacing: -1px; margin-bottom: 8px;
  background: linear-gradient(135deg, #fff 40%, rgba(255,255,255,0.7));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.section-subtitle { font-size: 1rem; color: var(--text-muted); max-width: 520px; margin: 0 auto; }

.about-section { background: linear-gradient(180deg, var(--bg-primary), var(--bg-secondary)); }
.skills-section { background: var(--bg-primary); }
.projects-section { background: linear-gradient(180deg, var(--bg-primary), var(--bg-secondary)); }
.experience-section { background: var(--bg-secondary); }
.research-section { background: var(--bg-primary); }
.certs-section { background: linear-gradient(180deg, var(--bg-primary), var(--bg-secondary)); }
.contact-section { background: var(--bg-secondary); }

.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ─── ABOUT SECTION ─── */
.about-grid { display: grid; grid-template-columns: 1fr 350px; gap: 40px; align-items: start; }
.about-lead { font-size: 1.05rem; color: var(--text-primary); margin-bottom: 12px; line-height: 1.6; }
.about-lead strong { color: var(--accent-cyan); }
.about-text p { color: var(--text-secondary); margin-bottom: 12px; font-size: 0.9rem; }
.about-text p strong { color: var(--accent-cyan); }

.about-highlights { margin: 28px 0; display: flex; flex-direction: column; gap: 16px; }
.highlight-item {
  display: flex; align-items: flex-start; gap: 16px; padding: 16px;
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-sm); transition: var(--transition);
}
.highlight-item:hover { border-color: var(--border-glow); background: var(--bg-card-hover); }
.highlight-item i { color: var(--accent-cyan); font-size: 1.2rem; margin-top: 2px; flex-shrink: 0; }
.highlight-item strong { display: block; font-size: 0.9rem; color: var(--text-primary); margin-bottom: 2px; }
.highlight-item span { font-size: 0.8rem; color: var(--text-muted); }
.about-actions { display: flex; gap: 16px; flex-wrap: wrap; }

.info-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius); padding: 24px; backdrop-filter: blur(10px); margin-bottom: 20px;
}
.info-card h3 { font-family: var(--font-heading); font-size: 1rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px; }
.info-list { display: flex; flex-direction: column; gap: 12px; }
.info-list li {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  font-size: 0.875rem; padding-bottom: 12px; border-bottom: 1px solid var(--border-color);
}
.info-list li:last-child { border-bottom: none; padding-bottom: 0; }
.info-label { color: var(--text-muted); display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.info-label i { color: var(--accent-cyan); width: 14px; }
.info-list span:last-child { color: var(--text-primary); font-weight: 500; text-align: right; }

.about-tools { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 24px; }
.about-tools h3 { font-family: var(--font-heading); font-size: 1rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px; }
.tools-grid { display: flex; flex-wrap: wrap; gap: 8px; }
.tool-tag {
  padding: 5px 12px; background: var(--gradient-subtle); border: 1px solid rgba(0,212,255,0.2);
  border-radius: 50px; font-size: 0.78rem; color: var(--accent-cyan); font-weight: 500; transition: var(--transition);
}
.tool-tag:hover { background: rgba(0,212,255,0.15); }

/* ─── SKILLS SECTION ─── */
.skills-categories { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-bottom: 40px; }
.skill-category {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius); padding: 20px; backdrop-filter: blur(10px); transition: var(--transition);
}
.skill-category:hover { border-color: var(--border-glow); box-shadow: var(--shadow-glow); }

.category-header { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
.category-icon {
  width: 40px; height: 40px; background: var(--gradient-main);
  border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center;
  font-size: 1rem; color: #fff;
}
.category-header h3 { font-family: var(--font-heading); font-size: 1rem; font-weight: 600; }

.skill-bars { display: flex; flex-direction: column; gap: 18px; }
.skill-bar-header { display: flex; justify-content: space-between; font-size: 0.82rem; color: var(--text-secondary); margin-bottom: 8px; font-weight: 500; }
.skill-pct { color: var(--accent-cyan); font-family: var(--font-mono); }
.skill-track { height: 6px; background: rgba(255,255,255,0.06); border-radius: 3px; overflow: hidden; }
.skill-fill { height: 100%; background: var(--gradient-main); border-radius: 3px; width: 0; transition: width 1.4s cubic-bezier(0.4, 0, 0.2, 1); box-shadow: 0 0 8px rgba(0,212,255,0.4); }

.tech-stack-title { font-family: var(--font-heading); font-size: 1.2rem; text-align: center; margin-bottom: 28px; color: var(--text-secondary); }
.tech-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(100px, 1fr)); gap: 14px; }
.tech-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-sm); padding: 20px 12px; text-align: center; transition: var(--transition); cursor: default;
}
.tech-card:hover { border-color: var(--border-glow); transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,212,255,0.15); }
.tech-icon { font-size: 1.8rem; margin-bottom: 8px; }
.tech-card span { font-size: 0.75rem; color: var(--text-secondary); font-weight: 500; }

/* ─── PROJECTS SECTION ─── */
.project-filters { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-bottom: 40px; }
.filter-btn {
  padding: 8px 20px; background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: 50px; color: var(--text-secondary); font-size: 0.85rem; font-weight: 500; cursor: pointer; transition: var(--transition);
}
.filter-btn:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); }
.filter-btn.active { background: var(--gradient-main); border-color: transparent; color: #fff; }

.projects-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(360px, 1fr)); gap: 24px; margin-bottom: 40px; }
.project-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius); padding: 24px; backdrop-filter: blur(10px); transition: var(--transition); position: relative; overflow: hidden;
}
.project-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 1px; background: var(--gradient-main); opacity: 0; transition: var(--transition); }
.project-card:hover::before { opacity: 1; }
.project-card:hover { border-color: var(--border-glow); transform: translateY(-6px); box-shadow: 0 20px 40px rgba(0,0,0,0.4), var(--shadow-glow); }
.project-card.hidden { display: none; }

.project-card-top { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 12px; }
.project-icon { font-size: 2.2rem; }
.project-links { display: flex; gap: 8px; }
.proj-link {
  width: 34px; height: 34px; display: flex; align-items: center; justify-content: center;
  background: rgba(255,255,255,0.06); border-radius: 6px; color: var(--text-muted); font-size: 0.85rem; transition: var(--transition);
}
.proj-link:hover { color: var(--accent-cyan); background: rgba(0,212,255,0.1); }

.project-tag-row { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 12px; }
.proj-tag { padding: 3px 10px; border-radius: 50px; font-size: 0.72rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; }
.tag-llm { background: rgba(0,212,255,0.12); color: var(--accent-cyan); }
.tag-rag { background: rgba(59,130,246,0.12); color: var(--accent-blue); }
.tag-cv { background: rgba(244,114,182,0.12); color: var(--accent-pink); }
.tag-edge { background: rgba(124,58,237,0.12); color: #a78bfa; }
.tag-medical { background: rgba(16,185,129,0.12); color: var(--accent-green); }
.tag-nlp { background: rgba(59,130,246,0.12); color: var(--accent-blue); }
.tag-fin { background: rgba(234,179,8,0.12); color: #fbbf24; }
.tag-mlops { background: rgba(124,58,237,0.12); color: #a78bfa; }
.tag-platform { background: rgba(0,212,255,0.12); color: var(--accent-cyan); }
.tag-diffusion { background: rgba(244,114,182,0.12); color: var(--accent-pink); }

.project-title { font-family: var(--font-heading); font-size: 1.1rem; font-weight: 600; margin-bottom: 10px; }
.project-desc { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; }

.project-metrics { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 16px; }
.project-metrics span { font-size: 0.78rem; color: var(--accent-green); font-weight: 600; display: flex; align-items: center; gap: 5px; }

.project-tech-row { display: flex; flex-wrap: wrap; gap: 6px; }
.project-tech-row span { padding: 3px 10px; background: rgba(255,255,255,0.04); border: 1px solid var(--border-color); border-radius: 4px; font-size: 0.75rem; font-family: var(--font-mono); color: var(--text-muted); }
.projects-cta { text-align: center; }

/* ─── EXPERIENCE / TIMELINE ─── */
.timeline { position: relative; max-width: 900px; margin: 0 auto; }
.timeline::before { content: ''; position: absolute; left: 20px; top: 8px; bottom: 8px; width: 2px; background: linear-gradient(to bottom, var(--accent-cyan), var(--accent-violet), transparent); }

.timeline-item { position: relative; padding-left: 68px; margin-bottom: 44px; }
.timeline-item:last-child { margin-bottom: 0; }

.timeline-dot {
  position: absolute; left: 12px; top: 6px; width: 18px; height: 18px;
  background: var(--gradient-main); border-radius: 50%; border: 3px solid var(--bg-secondary); box-shadow: 0 0 16px rgba(0,212,255,0.5); z-index: 1;
}

.timeline-content {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius);
  padding: 28px; backdrop-filter: blur(10px); transition: var(--transition);
}
.timeline-content:hover { border-color: var(--border-glow); box-shadow: var(--shadow-glow); }

.timeline-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 16px; gap: 16px; flex-wrap: wrap; }
.timeline-header h3 { font-family: var(--font-heading); font-size: 1.1rem; font-weight: 600; margin-bottom: 4px; }
.timeline-company { font-size: 0.875rem; color: var(--accent-cyan); display: flex; align-items: center; gap: 6px; }
.timeline-meta { text-align: right; flex-shrink: 0; }
.timeline-date { display: block; font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-muted); margin-bottom: 6px; }
.timeline-badge { display: inline-block; padding: 3px 10px; background: rgba(16,185,129,0.15); border: 1px solid rgba(16,185,129,0.3); border-radius: 50px; font-size: 0.72rem; color: var(--accent-green); font-weight: 600; }

.timeline-bullets { list-style: none; margin-bottom: 16px; }
.timeline-bullets li { position: relative; padding-left: 16px; color: var(--text-secondary); font-size: 0.875rem; margin-bottom: 8px; line-height: 1.7; }
.timeline-bullets li::before { content: '▸'; position: absolute; left: 0; color: var(--accent-cyan); font-size: 0.75rem; top: 2px; }

.timeline-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.timeline-tags span { padding: 3px 10px; background: var(--gradient-subtle); border: 1px solid rgba(0,212,255,0.15); border-radius: 4px; font-size: 0.75rem; font-family: var(--font-mono); color: var(--accent-cyan); }

/* ─── RESEARCH SECTION ─── */
.research-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(500px, 1fr)); gap: 24px; margin-bottom: 40px; }
.research-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius);
  padding: 28px; backdrop-filter: blur(10px); transition: var(--transition);
}
.research-card:hover { border-color: var(--border-glow); box-shadow: var(--shadow-glow); transform: translateY(-3px); }

.research-card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; }
.research-venue { padding: 4px 12px; border-radius: 50px; font-size: 0.72rem; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; }
.venue-q1 { background: rgba(16,185,129,0.12); color: var(--accent-green); border: 1px solid rgba(16,185,129,0.3); }
.venue-conf { background: rgba(0,212,255,0.12); color: var(--accent-cyan); border: 1px solid rgba(0,212,255,0.3); }
.venue-q2 { background: rgba(59,130,246,0.12); color: var(--accent-blue); border: 1px solid rgba(59,130,246,0.3); }
.research-year { font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-muted); }

.research-card h3 { font-family: var(--font-heading); font-size: 1rem; font-weight: 600; line-height: 1.4; margin-bottom: 8px; }
.research-authors { font-size: 0.82rem; color: var(--accent-cyan); margin-bottom: 6px; }
.research-venue-name { font-size: 0.82rem; color: var(--text-muted); margin-bottom: 12px; display: flex; align-items: center; gap: 6px; }
.research-abstract { font-size: 0.875rem; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; }

.research-metrics { display: flex; gap: 16px; margin-bottom: 16px; }
.research-metrics span { font-size: 0.8rem; color: var(--text-muted); display: flex; align-items: center; gap: 5px; }
.research-metrics .fa-star { color: var(--accent-cyan); }
.research-metrics .fa-award { color: #fbbf24; }

.research-links { display: flex; gap: 10px; }
.research-btn {
  padding: 6px 14px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-color); border-radius: 6px;
  font-size: 0.78rem; color: var(--text-secondary); display: flex; align-items: center; gap: 6px; transition: var(--transition);
}
.research-btn:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); background: rgba(0,212,255,0.06); }
.research-cta { text-align: center; }

/* ─── CERTIFICATIONS ─── */
.certs-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px; }
.cert-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius);
  padding: 20px 24px; display: flex; align-items: center; gap: 20px; backdrop-filter: blur(10px); transition: var(--transition); position: relative;
}
.cert-card:hover { border-color: var(--border-glow); transform: translateY(-3px); box-shadow: var(--shadow-glow); }
.award-card { border-color: rgba(251,191,36,0.2); }
.award-card:hover { border-color: rgba(251,191,36,0.5); }

.cert-logo { width: 48px; height: 48px; border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 1.4rem; flex-shrink: 0; }
.cert-logo.aws { background: rgba(255,153,0,0.15); color: #ff9900; }
.cert-logo.gcp { background: rgba(66,133,244,0.15); color: #4285f4; }
.cert-logo.azure { background: rgba(0,120,212,0.15); color: #0078d4; }
.cert-logo.deeplearning { background: rgba(0,212,255,0.1); color: var(--accent-cyan); font-family: var(--font-heading); font-size: 0.65rem; font-weight: 700; text-align: center; line-height: 1.2; }
.cert-logo.nvidia { background: rgba(118,185,0,0.15); color: #76b900; font-family: var(--font-heading); font-size: 0.6rem; font-weight: 800; text-align: center; }
.cert-logo.award { background: rgba(251,191,36,0.12); color: #fbbf24; }

.cert-info { flex: 1; }
.cert-info h3 { font-family: var(--font-heading); font-size: 0.9rem; font-weight: 600; margin-bottom: 3px; }
.cert-info p { font-size: 0.8rem; color: var(--text-secondary); margin-bottom: 4px; }
.cert-date { font-family: var(--font-mono); font-size: 0.72rem; color: var(--text-muted); }
.cert-verify { width: 32px; height: 32px; display: flex; align-items: center; justify-content: center; color: var(--text-muted); font-size: 0.75rem; transition: var(--transition); flex-shrink: 0; }
.cert-verify:hover { color: var(--accent-cyan); transform: scale(1.2); }

/* ─── CONTACT SECTION ─── */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: start; }

.contact-tagline h3 { font-family: var(--font-heading); font-size: 1.6rem; font-weight: 600; line-height: 1.4; margin-bottom: 16px; }
.contact-tagline p { color: var(--text-secondary); font-size: 0.95rem; line-height: 1.7; margin-bottom: 32px; }

.contact-channels { display: flex; flex-direction: column; gap: 12px; }
.contact-channel {
  display: flex; align-items: center; gap: 16px; padding: 16px 20px;
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-sm); transition: var(--transition);
}
.contact-channel:hover { border-color: var(--border-glow); transform: translateX(6px); }
.channel-icon { width: 40px; height: 40px; background: var(--gradient-subtle); border-radius: 8px; display: flex; align-items: center; justify-content: center; color: var(--accent-cyan); font-size: 1rem; flex-shrink: 0; }
.channel-icon.linkedin { background: rgba(10,102,194,0.15); color: #0a66c2; }
.channel-icon.github { background: rgba(255,255,255,0.08); color: var(--text-primary); }
.channel-icon.hf { background: rgba(255,196,0,0.1); }
.channel-info { flex: 1; }
.channel-info strong { display: block; font-size: 0.875rem; color: var(--text-primary); margin-bottom: 2px; }
.channel-info span { font-size: 0.8rem; color: var(--text-muted); }
.channel-arrow { color: var(--text-muted); font-size: 0.75rem; transition: var(--transition); }
.contact-channel:hover .channel-arrow { color: var(--accent-cyan); transform: translateX(4px); }

/* Contact Form */
.contact-form-wrapper { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 36px; backdrop-filter: blur(10px); }
.contact-form { display: flex; flex-direction: column; gap: 20px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 0.82rem; color: var(--text-secondary); font-weight: 500; }
.form-group input, .form-group select, .form-group textarea {
  background: rgba(255,255,255,0.04); border: 1px solid var(--border-color); border-radius: var(--radius-sm);
  padding: 12px 16px; color: var(--text-primary); font-family: var(--font-body); font-size: 0.9rem; outline: none; transition: var(--transition); width: 100%;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { border-color: var(--accent-cyan); box-shadow: 0 0 0 3px rgba(0,212,255,0.1); background: rgba(0,212,255,0.03); }
.form-group select option { background: var(--bg-secondary); }
.form-group textarea { resize: vertical; min-height: 120px; }
.form-group input::placeholder, .form-group textarea::placeholder { color: var(--text-muted); }

.form-success {
  display: none; align-items: center; gap: 10px; padding: 14px 16px;
  background: rgba(16,185,129,0.1); border: 1px solid rgba(16,185,129,0.3); border-radius: var(--radius-sm);
  color: var(--accent-green); font-size: 0.875rem;
}
.form-success.show { display: flex; }
.form-success i { font-size: 1.1rem; }

/* ─── FOOTER ─── */
.footer { background: var(--bg-primary); border-top: 1px solid var(--border-color); padding: 48px 0 0; }
.footer-container { max-width: 1240px; margin: 0 auto; padding: 0 24px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 32px; padding-bottom: 32px; }
.footer-brand p { font-size: 0.82rem; color: var(--text-muted); margin-top: 6px; }
.footer-links { display: flex; gap: 24px; justify-content: center; flex-wrap: wrap; }
.footer-links a { font-size: 0.875rem; color: var(--text-muted); transition: var(--transition); }
.footer-links a:hover { color: var(--accent-cyan); }
.footer-social { display: flex; gap: 14px; }
.footer-social a { color: var(--text-muted); font-size: 1rem; transition: var(--transition); }
.footer-social a:hover { color: var(--accent-cyan); transform: translateY(-2px); }
.footer-bottom { border-top: 1px solid var(--border-color); padding: 20px 24px; text-align: center; font-size: 0.82rem; color: var(--text-muted); }
.heart { color: var(--accent-pink); }

/* ─── SCROLL TO TOP ─── */
.scroll-top {
  position: fixed; bottom: 32px; right: 32px; width: 46px; height: 46px;
  background: var(--gradient-main); border-radius: 50%; display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 0.875rem; box-shadow: 0 4px 20px rgba(0,212,255,0.3);
  opacity: 0; visibility: hidden; transform: translateY(10px); transition: var(--transition); z-index: 500;
}
.scroll-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.scroll-top:hover { transform: translateY(-3px); box-shadow: 0 8px 28px rgba(0,212,255,0.5); }

/* ═══════════════════════════════════════════════ AI CHATBOT ═══ */
.chatbot-container {
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
}

.chat-toggle {
  width: 60px; height: 60px;
  border-radius: 50%;
  background: var(--gradient-main);
  color: #fff;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(0, 212, 255, 0.4);
  display: flex; justify-content: center; align-items: center;
  transition: var(--transition);
  animation: pulseChat 2s infinite;
}
.chat-toggle:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 25px rgba(124, 58, 237, 0.6);
}
@keyframes pulseChat {
  0% { box-shadow: 0 0 0 0 rgba(0, 212, 255, 0.4); }
  70% { box-shadow: 0 0 0 15px rgba(0, 212, 255, 0); }
  100% { box-shadow: 0 0 0 0 rgba(0, 212, 255, 0); }
}

.chat-window {
  width: 380px; height: 500px;
  max-height: 80vh;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  margin-bottom: 20px;
  display: flex; flex-direction: column;
  box-shadow: 0 10px 40px rgba(0,0,0,0.5), 0 0 20px rgba(0,212,255,0.1);
  overflow: hidden;
  opacity: 0; pointer-events: none;
  transform: translateY(20px) scale(0.95);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  transform-origin: bottom right;
}
.chat-window.active {
  opacity: 1; pointer-events: auto;
  transform: translateY(0) scale(1);
}

.chat-header {
  padding: 16px 20px;
  background: rgba(255,255,255,0.03);
  border-bottom: 1px solid var(--border-color);
  display: flex; justify-content: space-between; align-items: center;
}
.chat-header-info { display: flex; align-items: center; gap: 12px; }
.chat-avatar {
  position: relative;
  width: 40px; height: 40px;
  border-radius: 10px;
  background: var(--gradient-main);
  display: flex; justify-content: center; align-items: center;
  color: #fff; font-size: 1.2rem;
}
.status-indicator {
  position: absolute; bottom: -2px; right: -2px;
  width: 12px; height: 12px;
  background: #10b981;
  border: 2px solid #0f172a; border-radius: 50%;
}
.chat-title-group h4 { margin: 0; font-size: 1.1rem; color: var(--text-primary); }
.chat-title-group p { margin: 0; font-size: 0.8rem; color: var(--text-secondary); }
.chat-close { background: none; border: none; color: var(--text-secondary); font-size: 1.2rem; cursor: pointer; transition: var(--transition); }
.chat-close:hover { color: var(--accent-pink); transform: rotate(90deg); }

.chat-body {
  flex: 1; padding: 20px;
  overflow-y: auto; display: flex; flex-direction: column; gap: 16px;
  scroll-behavior: smooth;
}
.chat-body::-webkit-scrollbar { width: 6px; }
.chat-body::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 3px; }

.chat-message { display: flex; flex-direction: column; max-width: 85%; animation: slideInMsg 0.3s ease; }
@keyframes slideInMsg { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.chat-message.bot { align-self: flex-start; }
.chat-message.bot .msg-content {
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-color);
  border-bottom-left-radius: 4px;
}

.chat-message.user { align-self: flex-end; }
.chat-message.user .msg-content {
  background: var(--gradient-main);
  color: #fff;
  border-bottom-right-radius: 4px;
}

.msg-content {
  padding: 12px 16px;
  border-radius: 16px;
  font-size: 0.95rem; line-height: 1.5;
  color: var(--text-primary);
  word-wrap: break-word;
}
.msg-time { font-size: 0.75rem; color: var(--text-secondary); margin-top: 4px; padding: 0 4px; }
.chat-message.user .msg-time { text-align: right; }

.chat-footer {
  padding: 16px 20px;
  background: rgba(0,0,0,0.2);
  border-top: 1px solid var(--border-color);
}
#chatForm { display: flex; gap: 10px; }
#chatInput {
  flex: 1; padding: 12px 16px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  color: var(--text-primary);
  font-family: var(--font-body);
  transition: var(--transition);
}
#chatInput:focus { outline: none; border-color: var(--accent-cyan); background: rgba(255,255,255,0.1); }
#chatSubmit {
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--accent-cyan);
  color: #0f172a;
  border: none; cursor: pointer;
  display: flex; justify-content: center; align-items: center;
  font-size: 1.1rem; transition: var(--transition);
}
#chatSubmit:hover { background: #fff; transform: scale(1.05); }
#chatSubmit:active { transform: scale(0.95); }

.typing-indicator {
  display: flex; gap: 4px; padding: 12px 16px;
  background: rgba(255,255,255,0.05);
  border-radius: 16px; border-bottom-left-radius: 4px;
  width: fit-content;
}
.typing-indicator span {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--text-secondary);
  animation: bounce 1.4s infinite ease-in-out both;
}
.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }
@keyframes bounce { 0%, 80%, 100% { transform: scale(0); } 40% { transform: scale(1); } }

/* ─── RESPONSIVE ─── */
@media (max-width: 1100px) {
  .skills-categories { grid-template-columns: 1fr 1fr; }
  .research-grid { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .about-info { order: -1; }
}

@media (max-width: 900px) {
  .hero-content { grid-template-columns: 1fr; text-align: center; gap: 40px; }
  .hero-text { align-items: center; }
  .hero-image-container { width: 280px; height: 280px; margin: 0 auto; order: -1; }
  .hero-description { margin: 0 auto 32px; }
  .hero-badge { margin: 0 auto 20px; }
  .hero-stats { justify-content: center; }
  .hero-actions { justify-content: center; }
  .hero-social { justify-content: center; }
  .hero-name { letter-spacing: -1px; }
  .floating-badge { display: none; }

  .contact-grid { grid-template-columns: 1fr; }
  .skills-categories { grid-template-columns: 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
  .footer-container { grid-template-columns: 1fr; text-align: center; }
  .footer-social { justify-content: center; }
  .footer-links { gap: 16px; }
}

@media (max-width: 640px) {
  .section { padding: 70px 0; }
  .nav-links { display: none; }
  .nav-links.open { display: flex; flex-direction: column; position: fixed; top: 60px; left: 0; right: 0; background: rgba(5,5,16,0.97); backdrop-filter: blur(20px); padding: 24px; gap: 8px; border-bottom: 1px solid var(--border-color); }
  .nav-links.open .nav-link { padding: 12px 16px; }
  .nav-cta { display: none; }
  .hamburger { display: flex; }
  .hero { padding: 90px 24px 60px; }
  .timeline::before { left: 16px; }
  .timeline-item { padding-left: 52px; }
  .timeline-dot { left: 8px; }
  .timeline-header { flex-direction: column; }
  .timeline-meta { text-align: left; }
  .certs-grid { grid-template-columns: 1fr; }
  .contact-form-wrapper { padding: 24px; }
}