/* ==========================================================================
   PANAGIOTIS CHATZILEONTIADIS — MATHEMATICAL & TECH PORTFOLIO STYLES
   ========================================================================== */

:root {
  --bg-deep: #060913;
  --bg-surface: rgba(13, 20, 38, 0.72);
  --bg-surface-hover: rgba(20, 30, 56, 0.88);
  --bg-glass: rgba(10, 16, 31, 0.65);
  --border-subtle: rgba(56, 189, 248, 0.16);
  --border-glow: rgba(56, 189, 248, 0.45);

  --text-main: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --accent-cyan: #38bdf8;
  --accent-emerald: #10b981;
  --accent-violet: #8b5cf6;
  --accent-amber: #f59e0b;
  --accent-rose: #f43f5e;

  --gradient-primary: linear-gradient(135deg, #38bdf8 0%, #8b5cf6 55%, #10b981 100%);
  --gradient-cyber: linear-gradient(90deg, rgba(56, 189, 248, 0.15), rgba(139, 92, 246, 0.15));

  --font-sans: 'Inter', 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Space Grotesk', 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --shadow-glow: 0 0 35px -5px rgba(56, 189, 248, 0.22);
  --shadow-card: 0 20px 45px -15px rgba(0, 0, 0, 0.7);
  --radius-lg: 18px;
  --radius-md: 12px;
  --radius-sm: 8px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.65;
  overflow-x: hidden;
}

body {
  background-color: var(--bg-deep);
  color: var(--text-main);
  position: relative;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: #050811;
}
::-webkit-scrollbar-thumb {
  background: #1e293b;
  border-radius: 4px;
  border: 1px solid rgba(56, 189, 248, 0.2);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-cyan);
}

/* Background Mathematical Canvas & Grid Overlay */
#math-bg-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

.math-grid-overlay {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(56, 189, 248, 0.03) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(circle at 50% 35%, black 30%, transparent 90%);
  -webkit-mask-image: radial-gradient(circle at 50% 35%, black 30%, transparent 90%);
}

/* Floating Ambient Math Formulas */
.floating-formulas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}

.floating-formula {
  position: absolute;
  font-family: var(--font-mono);
  color: rgba(56, 189, 248, 0.08);
  font-size: 0.95rem;
  user-select: none;
  white-space: nowrap;
  animation: floatFormula 22s ease-in-out infinite alternate;
}

@keyframes floatFormula {
  0% {
    transform: translateY(0px) translateX(0px) rotate(-2deg);
  }
  100% {
    transform: translateY(-30px) translateX(20px) rotate(2deg);
  }
}

/* Main Content Wrapper */
.site-wrapper {
  position: relative;
  z-index: 2;
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ==========================================================================
   HEADER & NAVIGATION
   ========================================================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(6, 9, 19, 0.78);
  border-bottom: 1px solid var(--border-subtle);
  transition: all 0.3s ease;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 74px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-main);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

.brand-symbol {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.2), rgba(139, 92, 246, 0.25));
  border: 1px solid var(--border-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  font-weight: 700;
  font-size: 1.1rem;
  box-shadow: 0 0 18px rgba(56, 189, 248, 0.25);
}

.brand-text span {
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  margin-left: 4px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
  padding: 0.3rem 0;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent-cyan);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--gradient-primary);
  transition: width 0.25s ease;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.attractor-pill {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.attractor-pill:hover {
  border-color: var(--accent-cyan);
  color: var(--text-main);
  box-shadow: 0 0 12px rgba(56, 189, 248, 0.2);
}

.attractor-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
  animation: pulseDot 2s infinite;
}

@keyframes pulseDot {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.35); opacity: 0.65; }
}

.lang-switch {
  display: inline-flex;
  background: rgba(15, 23, 42, 0.9);
  border: 1px solid var(--border-subtle);
  border-radius: 999px;
  padding: 3px;
}

.lang-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.3rem 0.65rem;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.lang-btn.active {
  background: var(--accent-cyan);
  color: #060913;
  box-shadow: 0 0 12px rgba(56, 189, 248, 0.4);
}

.mobile-menu-btn {
  display: none;
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  border-radius: 8px;
  padding: 0.45rem 0.65rem;
  cursor: pointer;
  font-size: 1.1rem;
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */
.hero {
  min-height: 100vh;
  padding: 8.5rem 0 4.5rem;
  display: flex;
  align-items: center;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.3fr 0.9fr;
  gap: 3.5rem;
  align-items: center;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.4rem 0.95rem;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.35);
  color: #34d399;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  margin-bottom: 1.4rem;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.35rem, 4.4vw, 3.8rem);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}

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

.hero-role-wrapper {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-mono);
  font-size: clamp(1rem, 1.8vw, 1.25rem);
  color: var(--accent-cyan);
  margin-bottom: 1.4rem;
  min-height: 2rem;
}

.cursor-blink {
  display: inline-block;
  width: 9px;
  height: 1.2em;
  background: var(--accent-cyan);
  vertical-align: middle;
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

.hero-description {
  color: var(--text-secondary);
  font-size: 1.06rem;
  max-width: 630px;
  margin-bottom: 1.75rem;
}

/* Mathematical Identity Banner in Hero */
.hero-equation-box {
  background: rgba(10, 17, 34, 0.78);
  border: 1px solid var(--border-subtle);
  border-left: 3px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 0.95rem 1.25rem;
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.equation-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-violet);
  display: block;
  margin-bottom: 0.25rem;
}

.equation-formula {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  color: #e2e8f0;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.85rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.94rem;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.25s ease;
  border: 1px solid transparent;
}

.btn-primary {
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  color: #ffffff;
  box-shadow: 0 10px 25px -5px rgba(14, 165, 233, 0.45);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 15px 30px -5px rgba(14, 165, 233, 0.65);
}

.btn-secondary {
  background: rgba(15, 23, 42, 0.8);
  color: var(--text-main);
  border-color: var(--border-glow);
}

.btn-secondary:hover {
  background: rgba(56, 189, 248, 0.12);
  transform: translateY(-2px);
}

/* Hero Metrics Strip */
.hero-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(148, 163, 184, 0.14);
}

.metric-item {
  display: flex;
  flex-direction: column;
}

.metric-value {
  font-family: var(--font-display);
  font-size: 1.65rem;
  font-weight: 800;
  color: var(--text-main);
}

.metric-value span {
  color: var(--accent-cyan);
}

.metric-label {
  font-size: 0.78rem;
  color: var(--text-secondary);
}

/* Hero Right: Holographic Profile & Math Telemetry Card */
.hero-visual-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 24px;
  padding: 1.75rem;
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow-card), var(--shadow-glow);
  position: relative;
  overflow: hidden;
}

.hero-visual-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: conic-gradient(from 0deg, transparent 0deg, rgba(56, 189, 248, 0.12) 60deg, transparent 120deg);
  animation: rotateConic 14s linear infinite;
  pointer-events: none;
}

@keyframes rotateConic {
  100% { transform: rotate(360deg); }
}

.visual-card-inner {
  position: relative;
  z-index: 2;
}

.profile-frame-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.2rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.window-dots {
  display: flex;
  gap: 6px;
}

.window-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.window-dots span:nth-child(1) { background: #f43f5e; }
.window-dots span:nth-child(2) { background: #f59e0b; }
.window-dots span:nth-child(3) { background: #10b981; }

.avatar-toggle-bar {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  margin-bottom: 1.1rem;
}

.mode-chip {
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.mode-chip.active {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  background: rgba(56, 189, 248, 0.12);
}

.avatar-stage {
  position: relative;
  width: 220px;
  height: 220px;
  margin: 0 auto 1.4rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.orbital-ring {
  position: absolute;
  inset: -12px;
  border-radius: 50%;
  border: 1px dashed rgba(56, 189, 248, 0.4);
  animation: spinOrbit 24s linear infinite;
}

.orbital-ring-2 {
  position: absolute;
  inset: -24px;
  border-radius: 50%;
  border: 1px solid rgba(139, 92, 246, 0.25);
  animation: spinOrbitReverse 32s linear infinite;
}

@keyframes spinOrbit {
  100% { transform: rotate(360deg); }
}

@keyframes spinOrbitReverse {
  100% { transform: rotate(-360deg); }
}

.profile-photo-img {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--accent-cyan);
  box-shadow: 0 0 30px rgba(56, 189, 248, 0.35);
  transition: all 0.35s ease;
}

#avatar-geometry-canvas {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle at center, rgba(14, 165, 233, 0.18), rgba(6, 9, 19, 0.95));
  border: 2px solid var(--accent-violet);
  box-shadow: 0 0 30px rgba(139, 92, 246, 0.35);
  display: none;
}

.telemetry-list {
  display: grid;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  background: rgba(6, 9, 19, 0.75);
  padding: 1rem;
  border-radius: var(--radius-md);
  border: 1px solid rgba(56, 189, 248, 0.14);
}

.telemetry-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.telemetry-key {
  color: var(--text-secondary);
}

.telemetry-val {
  color: var(--accent-cyan);
  font-weight: 600;
}

/* ==========================================================================
   SECTIONS GENERAL
   ========================================================================== */
section {
  padding: 5.5rem 0;
  position: relative;
}

.section-header {
  margin-bottom: 3.2rem;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.6rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.85rem, 3vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-subtitle {
  color: var(--text-secondary);
  max-width: 680px;
  font-size: 1rem;
}

/* ==========================================================================
   INTERACTIVE MATHEMATICAL ODDS & STOCHASTIC SIMULATOR LAB
   ========================================================================== */
.math-lab-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2rem;
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow-card), var(--shadow-glow);
}

.lab-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.75rem;
  border-bottom: 1px solid rgba(148, 163, 184, 0.15);
  padding-bottom: 1rem;
}

.lab-tab-btn {
  background: rgba(15, 23, 42, 0.75);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.84rem;
  padding: 0.6rem 1.15rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.lab-tab-btn.active {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.2), rgba(139, 92, 246, 0.2));
  border-color: var(--accent-cyan);
  color: var(--text-main);
  box-shadow: 0 0 15px rgba(56, 189, 248, 0.25);
}

.lab-grid {
  display: grid;
  grid-template-columns: 1fr 1.25fr;
  gap: 2rem;
  align-items: start;
}

.lab-controls {
  background: rgba(6, 9, 19, 0.65);
  border: 1px solid rgba(56, 189, 248, 0.14);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}

.slider-group {
  margin-bottom: 1.25rem;
}

.slider-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.86rem;
  margin-bottom: 0.45rem;
}

.slider-val {
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  font-weight: 700;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent-cyan);
  background: #1e293b;
  height: 6px;
  border-radius: 4px;
  cursor: pointer;
}

.lab-kpis {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.8rem;
  margin-top: 1.25rem;
}

.kpi-box {
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(56, 189, 248, 0.16);
  border-radius: var(--radius-sm);
  padding: 0.85rem;
  text-align: center;
}

.kpi-title {
  font-size: 0.72rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  margin-bottom: 0.3rem;
}

.kpi-num {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-emerald);
}

.lab-canvas-box {
  background: rgba(6, 9, 19, 0.85);
  border: 1px solid rgba(56, 189, 248, 0.18);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.lab-canvas-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-secondary);
}

#poisson-canvas {
  width: 100%;
  height: 270px;
  display: block;
}

.matrix-legend {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   CAREER TIMELINE (EXPERIENCE)
   ========================================================================== */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--accent-cyan), var(--accent-violet), var(--accent-emerald));
}

.timeline-item {
  position: relative;
  margin-bottom: 2.2rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  backdrop-filter: blur(14px);
  transition: all 0.25s ease;
}

.timeline-item:hover {
  border-color: var(--border-glow);
  transform: translateX(5px);
  box-shadow: var(--shadow-glow);
}

.timeline-dot {
  position: absolute;
  left: -2.38rem;
  top: 1.9rem;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-deep);
  border: 3px solid var(--accent-cyan);
  box-shadow: 0 0 12px var(--accent-cyan);
}

.timeline-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.65rem;
}

.timeline-period {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-cyan);
  background: rgba(56, 189, 248, 0.1);
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
  border: 1px solid rgba(56, 189, 248, 0.25);
}

.timeline-company {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent-emerald);
}

.timeline-role {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 0.55rem;
}

.timeline-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ==========================================================================
   PROJECTS GRID
   ========================================================================== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.75rem;
}

.project-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.85rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(16px);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.project-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-card), var(--shadow-glow);
}

.project-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.1rem;
}

.project-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  font-weight: 700;
}

.project-math-badge {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent-violet);
  background: rgba(139, 92, 246, 0.12);
  border: 1px solid rgba(139, 92, 246, 0.3);
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
}

.project-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.7rem;
}

.project-desc {
  color: var(--text-secondary);
  font-size: 0.93rem;
  margin-bottom: 1.4rem;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tech-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #cbd5e1;
  background: rgba(15, 23, 42, 0.9);
  border: 1px solid rgba(148, 163, 184, 0.2);
  padding: 0.25rem 0.65rem;
  border-radius: 6px;
}

/* ==========================================================================
   SKILLS & MATHEMATICAL ARSENAL
   ========================================================================== */
.skills-layout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.skill-category-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.6rem;
  backdrop-filter: blur(14px);
}

.skill-cat-title {
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 700;
  margin-bottom: 1.1rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--accent-cyan);
}

.skill-bar-item {
  margin-bottom: 1rem;
}

.skill-bar-top {
  display: flex;
  justify-content: space-between;
  font-size: 0.86rem;
  margin-bottom: 0.35rem;
}

.skill-bar-pct {
  font-family: var(--font-mono);
  color: var(--accent-emerald);
  font-size: 0.78rem;
}

.skill-track {
  width: 100%;
  height: 7px;
  background: rgba(15, 23, 42, 0.9);
  border-radius: 999px;
  overflow: hidden;
}

.skill-fill {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: 999px;
}

/* ==========================================================================
   EDUCATION, GEOPHYSICS RESEARCH & CERTIFICATIONS
   ========================================================================== */
.edu-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 2rem;
}

.edu-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  margin-bottom: 1.5rem;
}

.edu-card h3 {
  font-family: var(--font-display);
  font-size: 1.22rem;
  margin-bottom: 0.35rem;
}

.edu-inst {
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.84rem;
  margin-bottom: 0.75rem;
}

.edu-details {
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.edu-details ul {
  margin-top: 0.6rem;
  padding-left: 1.2rem;
}

.edu-details li {
  margin-bottom: 0.4rem;
}

.cert-list {
  display: grid;
  gap: 0.85rem;
}

.cert-item {
  background: rgba(13, 20, 38, 0.78);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1rem 1.2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  transition: all 0.2s ease;
}

.cert-item:hover {
  border-color: var(--accent-cyan);
  transform: translateX(4px);
}

.cert-name {
  font-weight: 600;
  font-size: 0.93rem;
}

.cert-org {
  color: var(--text-secondary);
  font-size: 0.8rem;
}

.cert-year {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--accent-emerald);
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  white-space: nowrap;
}

/* ==========================================================================
   CONTACT & FOOTER
   ========================================================================== */
.contact-card {
  background: linear-gradient(135deg, rgba(13, 20, 38, 0.9), rgba(15, 23, 42, 0.85));
  border: 1px solid var(--border-glow);
  border-radius: 24px;
  padding: 3rem;
  text-align: center;
  box-shadow: var(--shadow-card), var(--shadow-glow);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
  margin-top: 2rem;
}

.contact-box {
  background: rgba(6, 9, 19, 0.75);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.35rem;
  text-decoration: none;
  color: var(--text-main);
  transition: all 0.25s ease;
}

.contact-box:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-4px);
}

.contact-box-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  margin-bottom: 0.35rem;
}

.contact-box-val {
  font-weight: 600;
  font-size: 1rem;
}

footer {
  padding: 2.5rem 0;
  border-top: 1px solid rgba(148, 163, 184, 0.12);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   RESPONSIVE DESIGN
   ========================================================================== */
@media (max-width: 992px) {
  .hero-grid,
  .lab-grid,
  .edu-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 7rem;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 74px;
    left: 0;
    right: 0;
    background: rgba(6, 9, 19, 0.96);
    flex-direction: column;
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-subtle);
  }

  .nav-links.open {
    display: flex;
  }

  .mobile-menu-btn {
    display: inline-flex;
  }
}

@media (max-width: 640px) {
  .hero-metrics,
  .lab-kpis {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-card {
    padding: 1.75rem 1.25rem;
  }

  .attractor-pill span:not(.attractor-dot) {
    display: none;
  }
}