/* ============================
   DESIGN SYSTEM — Elango Dilliraj Portfolio
   ============================ */

@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500&family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700;800&display=swap');

/* --- CSS Custom Properties --- */
:root {
  --bg-primary: #080c14;
  --bg-secondary: #0d1321;
  --bg-card: rgba(15, 23, 42, 0.55);
  --bg-card-hover: rgba(20, 30, 55, 0.7);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-glass-hover: rgba(255, 255, 255, 0.15);

  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-purple: #7f00ff;
  --accent-violet: #e100ff;
  --accent-green: #00e676;

  --gradient-cyan: linear-gradient(135deg, #00f2fe, #4facfe);
  --gradient-purple: linear-gradient(135deg, #7f00ff, #e100ff);
  --gradient-mixed: linear-gradient(135deg, #00f2fe, #7f00ff, #e100ff);

  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --font-heading: 'Outfit', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'Fira Code', monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 50%;

  --shadow-glow-cyan: 0 0 20px rgba(0, 242, 254, 0.15);
  --shadow-glow-purple: 0 0 20px rgba(127, 0, 255, 0.15);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);

  --transition-fast: 0.2s ease;
  --transition-base: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 242, 254, 0.15) rgba(8, 12, 20, 0.5);
}

/* Webkit Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(8, 12, 20, 0.5);
  border-left: 1px solid var(--border-glass);
}

::-webkit-scrollbar-thumb {
  background: rgba(0, 242, 254, 0.15);
  border-radius: 4px;
  border: 2px solid rgba(8, 12, 20, 0.5);
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 242, 254, 0.35);
}

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  min-height: 100vh;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: color var(--transition-fast);
}
a:hover {
  color: var(--accent-blue);
}

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

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
}

/* --- Canvas Background --- */
#particle-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

/* --- Navigation --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 0.8rem 2rem;
  backdrop-filter: blur(18px) saturate(1.8);
  -webkit-backdrop-filter: blur(18px) saturate(1.8);
  background: rgba(8, 12, 20, 0.75);
  border-bottom: 1px solid var(--border-glass);
  transition: background var(--transition-base);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 800;
  background: var(--gradient-cyan);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 0.3rem;
}

.nav-links a {
  padding: 0.5rem 1rem;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  position: relative;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
  background: rgba(0, 242, 254, 0.08);
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background: var(--gradient-cyan);
  border-radius: 2px;
}

/* Mobile menu toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

/* --- Main Content Wrapper --- */
.main-content {
  position: relative;
  z-index: 1;
  padding-top: 80px;
}

/* --- Sections --- */
.section {
  max-width: 1200px;
  margin: 0 auto;
  padding: 5rem 2rem;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 3px;
  margin-bottom: 0.6rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.section-label::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--accent-cyan);
}

.section-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  margin-bottom: 1.2rem;
  background: linear-gradient(135deg, var(--text-primary), var(--text-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.8;
  margin-bottom: 3rem;
}

/* --- Glass Card --- */
.glass-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: all var(--transition-base);
}

.glass-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glass-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

/* ============================
   HERO SECTION
   ============================ */
.hero {
  min-height: calc(100vh - 80px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}

.hero-inner {
  max-width: 960px;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
}

.hero-text {
  flex: 1;
}

.hero-greeting {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--accent-cyan);
  margin-bottom: 0.8rem;
  letter-spacing: 1px;
}

.hero-name {
  font-size: clamp(2.5rem, 5.5vw, 4rem);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 0.6rem;
}

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

.hero-role {
  font-size: 1.15rem;
  color: var(--text-secondary);
  font-weight: 400;
  margin-bottom: 1rem;
}

.hero-tagline {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  min-height: 1.7em;
}

.hero-tagline .cursor {
  display: inline-block;
  width: 2px;
  height: 1.1em;
  background: var(--accent-cyan);
  margin-left: 2px;
  animation: blink 1s infinite;
  vertical-align: text-bottom;
}

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

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.8rem;
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
}

.btn-primary {
  background: var(--gradient-cyan);
  color: var(--bg-primary);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-cyan);
  color: var(--bg-primary);
}

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-glass-hover);
}

.btn-outline:hover {
  border-color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.05);
  color: var(--accent-cyan);
}

/* Hero Image */
.hero-image {
  flex-shrink: 0;
}

.profile-frame {
  width: 260px;
  height: 340px;
  border-radius: var(--radius-xl);
  padding: 4px;
  background: var(--gradient-mixed);
  position: relative;
  animation: profileGlow 4s ease-in-out infinite alternate;
  overflow: hidden;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  cursor: pointer;
}

.profile-frame:hover {
  transform: translateY(-6px) scale(1.03);
  box-shadow: 0 0 40px rgba(0, 242, 254, 0.35), 0 0 80px rgba(127, 0, 255, 0.2);
}

.profile-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: calc(var(--radius-xl) - 2px);
  border: 4px solid var(--bg-primary);
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.profile-frame:hover img {
  transform: scale(1.08);
}

@keyframes profileGlow {
  0% { box-shadow: 0 0 25px rgba(0, 242, 254, 0.25), 0 0 60px rgba(0, 242, 254, 0.08); }
  100% { box-shadow: 0 0 30px rgba(127, 0, 255, 0.3), 0 0 70px rgba(225, 0, 255, 0.1); }
}

/* Brief Intro Section */
.intro-section {
  max-width: 900px;
  margin: 0 auto;
  padding: 3rem 2rem 1rem;
  text-align: center;
}

.intro-section .intro-text {
  font-size: 1.08rem;
  color: var(--text-secondary);
  line-height: 1.9;
  max-width: 750px;
  margin: 0 auto;
}

.intro-section .intro-text .highlight {
  color: var(--accent-cyan);
  font-weight: 600;
}

.hero-contact-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.hero-contact-row .contact-badge {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-glass);
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
}

.hero-contact-row .contact-badge i {
  color: var(--accent-cyan);
}

.btn-contact {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: rgba(15, 23, 42, 0.55);
  border: 1px solid var(--border-glass);
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius-sm);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  transition: all var(--transition-fast);
}

.btn-contact i {
  font-size: 0.95rem;
}

.btn-contact:hover {
  color: var(--text-primary);
  background: rgba(0, 242, 254, 0.08);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-cyan);
}

/* ============================
   ACADEMIC TIMELINE
   ============================ */
.timeline {
  position: relative;
  padding-left: 2.5rem;
}

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

.timeline-item {
  position: relative;
  margin-bottom: 2.5rem;
  padding-left: 1.5rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2.65rem;
  top: 0.4rem;
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
  background: var(--accent-cyan);
  box-shadow: 0 0 12px rgba(0, 242, 254, 0.5);
  border: 2px solid var(--bg-primary);
}

.timeline-year {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-cyan);
  margin-bottom: 0.3rem;
  letter-spacing: 1px;
}

.timeline-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.2rem;
}

.timeline-institution {
  font-size: 0.92rem;
  color: var(--text-secondary);
  font-style: italic;
  margin-bottom: 0.6rem;
}

.timeline-highlights {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.timeline-highlights li {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8rem;
  color: var(--text-secondary);
  background: rgba(0, 242, 254, 0.06);
  padding: 0.3rem 0.8rem;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(0, 242, 254, 0.1);
}

.timeline-highlights li::before {
  content: '▹';
  color: var(--accent-cyan);
}

/* ============================
   CERTIFICATIONS PREVIEW (Home)
   ============================ */
.cert-preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.cert-preview-card {
  display: block;
  color: inherit;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
}

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

.cert-preview-card img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-bottom: 1px solid var(--border-glass);
}

.cert-preview-info {
  padding: 1.2rem 1.5rem;
}

.cert-preview-info h4 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
}

.cert-preview-info p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.cert-preview-info .cert-org {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-cyan);
  margin-top: 0.5rem;
}

.cert-view-all {
  text-align: center;
  margin-top: 2.5rem;
}

/* ============================
   CONNECT SECTION
   ============================ */
.connect-section {
  padding: 5rem 2rem;
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.connect-form {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  margin-top: 2rem;
  text-align: left;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-group label {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
}

.form-group input,
.form-group textarea {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 0.85rem 1.2rem;
  font-family: var(--font-body);
  font-size: 0.92rem;
  color: var(--text-primary);
  transition: all var(--transition-fast);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(0, 242, 254, 0.08);
}

.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

.connect-socials {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-top: 2rem;
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-glass);
  background: var(--bg-card);
  color: var(--text-secondary);
  font-size: 1.2rem;
  transition: all var(--transition-base);
}

.social-link:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  transform: translateY(-3px);
  box-shadow: var(--shadow-glow-cyan);
}

.form-status {
  text-align: center;
  padding: 0.8rem;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  display: none;
}

.form-status.success {
  display: block;
  background: rgba(0, 230, 118, 0.1);
  color: var(--accent-green);
  border: 1px solid rgba(0, 230, 118, 0.2);
}

/* ============================
   TECH SKILLS PAGE
   ============================ */
.skills-categories {
  display: flex;
  flex-direction: column;
  gap: 3.5rem;
}

.skill-category {
  animation: fadeInUp 0.6s ease forwards;
}

.category-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.8rem;
}

.category-icon {
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  font-size: 1.5rem;
  flex-shrink: 0;
}

.category-icon.ai { background: linear-gradient(135deg, rgba(127, 0, 255, 0.2), rgba(225, 0, 255, 0.1)); }
.category-icon.math { background: linear-gradient(135deg, rgba(0, 242, 254, 0.2), rgba(79, 172, 254, 0.1)); }
.category-icon.prog { background: linear-gradient(135deg, rgba(0, 230, 118, 0.2), rgba(0, 242, 254, 0.1)); }

.category-header h3 {
  font-size: 1.4rem;
  font-weight: 700;
}

.category-header p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.2rem;
}

.skill-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.skill-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-cyan);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.skill-card:hover {
  border-color: var(--border-glass-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

.skill-card:hover::before {
  opacity: 1;
}

.skill-card {
  cursor: pointer;
}

.skill-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.8rem;
}

/* Expandable Skill Details */
.skill-detail {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.45s cubic-bezier(0.4, 0, 0.2, 1), margin 0.3s ease, opacity 0.3s ease;
  opacity: 0;
  margin-top: 0;
}

.skill-card.expanded .skill-detail {
  max-height: 500px;
  opacity: 1;
  margin-top: 1rem;
}

.skill-detail-inner {
  border-top: 1px solid var(--border-glass);
  padding-top: 0.8rem;
}

.skill-detail-inner p {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 0.5rem;
}

.skill-detail-inner p strong {
  color: var(--accent-cyan);
  font-weight: 600;
}

.skill-detail-inner p.purple strong {
  color: var(--accent-purple);
}

.skill-card .expand-hint {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  margin-top: 0.6rem;
  transition: color var(--transition-fast);
}

.skill-card.expanded .expand-hint {
  color: var(--accent-cyan);
}

.skill-card.expanded {
  border-color: rgba(0, 242, 254, 0.2);
  background: var(--bg-card-hover);
}

.skill-bar {
  height: 6px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 3px;
  overflow: hidden;
  margin-top: 0.5rem;
}

.skill-bar-fill {
  height: 100%;
  border-radius: 3px;
  background: var(--gradient-cyan);
  transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
  width: 0;
}

.skill-bar-fill.purple {
  background: var(--gradient-purple);
}

.skill-bar-fill.green {
  background: linear-gradient(135deg, #00e676, #00f2fe);
}

.skill-card .skill-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.skill-card .skill-percent {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
}

/* ============================
   SOFT SKILLS PAGE
   ============================ */
.soft-skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
}

.soft-skill-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  text-align: center;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.soft-skill-card:hover {
  border-color: var(--accent-purple);
  transform: translateY(-6px);
  box-shadow: var(--shadow-glow-purple);
}

.soft-skill-icon {
  width: 70px;
  height: 70px;
  margin: 0 auto 1.5rem;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  background: rgba(127, 0, 255, 0.1);
  border: 1px solid rgba(127, 0, 255, 0.15);
}

.soft-skill-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
}

.soft-skill-card .role-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-purple);
  background: rgba(127, 0, 255, 0.08);
  padding: 0.25rem 0.7rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  border: 1px solid rgba(127, 0, 255, 0.12);
}

.soft-skill-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.soft-skill-details {
  list-style: none;
  margin-top: 1.2rem;
  text-align: left;
}

.soft-skill-details li {
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: 0.4rem 0;
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.soft-skill-details li::before {
  content: '◆';
  color: var(--accent-purple);
  font-size: 0.55rem;
  margin-top: 0.35rem;
  flex-shrink: 0;
}

/* ============================
   CERTIFICATIONS & PROJECTS PAGE
   ============================ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 2rem;
  margin-bottom: 4rem;
}

.project-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: all var(--transition-base);
  position: relative;
}

.project-card:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow-cyan);
}

.project-status {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.project-status.completed {
  background: rgba(0, 230, 118, 0.1);
  color: var(--accent-green);
  border: 1px solid rgba(0, 230, 118, 0.15);
}

.project-status.upcoming {
  background: rgba(79, 172, 254, 0.1);
  color: var(--accent-blue);
  border: 1px solid rgba(79, 172, 254, 0.15);
}

.project-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
}

.project-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 1.2rem;
}

.project-tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.project-tech-tags span {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: rgba(0, 242, 254, 0.06);
  color: var(--accent-cyan);
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(0, 242, 254, 0.1);
}

/* Cert expandable cards */
.cert-deep-grid {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.cert-deep-grid hr {
  display: none;
}

.cert-expand-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
}

.cert-expand-card:hover {
  border-color: var(--border-glass-hover);
  box-shadow: var(--shadow-card);
}

.cert-expand-card.expanded {
  border-color: rgba(127, 0, 255, 0.25);
  box-shadow: 0 0 24px rgba(127, 0, 255, 0.1), var(--shadow-card);
}

/* --- Header (always visible compact row) --- */
.cert-expand-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.2rem 1.5rem;
  cursor: pointer;
  transition: background var(--transition-fast);
  user-select: none;
}

.cert-expand-header:hover {
  background: rgba(255, 255, 255, 0.02);
}

.cert-deep-number {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  background: var(--gradient-purple);
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 700;
  color: white;
  flex-shrink: 0;
}

/* Small thumbnail */
.cert-thumb-wrap {
  width: 64px;
  height: 44px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  flex-shrink: 0;
  border: 1px solid var(--border-glass);
  transition: border-color var(--transition-fast);
}

.cert-expand-card:hover .cert-thumb-wrap,
.cert-expand-card.expanded .cert-thumb-wrap {
  border-color: rgba(127, 0, 255, 0.3);
}

.cert-thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* Header text */
.cert-header-text {
  flex: 1;
  min-width: 0;
}

.cert-header-text h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 0.15rem;
  line-height: 1.3;
}

.cert-deep-org {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-purple);
  margin-bottom: 0.3rem;
}

.cert-brief {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* Expand chevron icon */
.cert-expand-icon {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full);
  background: rgba(127, 0, 255, 0.08);
  border: 1px solid rgba(127, 0, 255, 0.12);
  color: var(--text-muted);
  transition: all var(--transition-base);
}

.cert-expand-card.expanded .cert-expand-icon {
  transform: rotate(180deg);
  background: rgba(127, 0, 255, 0.15);
  color: var(--accent-purple);
  border-color: rgba(127, 0, 255, 0.3);
}

/* --- Expandable body (hidden by default) --- */
.cert-expand-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.55s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.35s ease;
  opacity: 0;
}

.cert-expand-card.expanded .cert-expand-body {
  max-height: 800px;
  opacity: 1;
}

.cert-expand-inner {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 2rem;
  padding: 0 1.5rem 1.8rem 1.5rem;
  border-top: 1px solid var(--border-glass);
  padding-top: 1.5rem;
  margin-top: 0;
}

/* Expanded image */
.cert-expand-image {
  position: relative;
}

.cert-expand-image img {
  width: 100%;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-glass);
  cursor: pointer;
  transition: all var(--transition-base);
}

.cert-expand-image img:hover {
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-glow-cyan);
  transform: scale(1.02);
}

.cert-img-hint {
  display: block;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
  opacity: 0.7;
  transition: opacity var(--transition-fast);
}

.cert-expand-image:hover .cert-img-hint {
  opacity: 1;
  color: var(--accent-cyan);
}

/* Detail text */
.cert-expand-details {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.cert-expand-details p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.cert-expand-details p strong {
  color: var(--accent-cyan);
  font-weight: 600;
}

.cert-expand-details p.purple strong {
  color: var(--accent-purple);
}

.verify-link {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  margin-top: 0.4rem;
  padding: 0.4rem 0.8rem;
  background: rgba(0, 242, 254, 0.06);
  border: 1px solid rgba(0, 242, 254, 0.12);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.verify-link:hover {
  background: rgba(0, 242, 254, 0.12);
  border-color: var(--accent-cyan);
}

/* ============================
   FULLSCREEN LIGHTBOX OVERLAY
   ============================ */
.cert-lightbox-overlay {
  position: fixed;
  inset: 0;
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.4s ease, visibility 0.4s ease;
  cursor: zoom-out;
}

.cert-lightbox-overlay.active {
  opacity: 1;
  visibility: visible;
}

.cert-lightbox-overlay img {
  max-width: 92vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-lg);
  border: 2px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 20px 80px rgba(0, 0, 0, 0.6);
  transform: scale(0.92);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.cert-lightbox-overlay.active img {
  transform: scale(1);
}

.cert-lightbox-close {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-primary);
  transition: all var(--transition-fast);
  z-index: 10001;
}

.cert-lightbox-close:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  transform: scale(1.1);
}

/* ============================
   INTERESTS PAGE
   ============================ */
.interests-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.interest-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  text-align: center;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.interest-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.interest-card:nth-child(1)::after { background: linear-gradient(135deg, rgba(0, 242, 254, 0.06), transparent); }
.interest-card:nth-child(2)::after { background: linear-gradient(135deg, rgba(127, 0, 255, 0.06), transparent); }
.interest-card:nth-child(3)::after { background: linear-gradient(135deg, rgba(0, 230, 118, 0.06), transparent); }
.interest-card:nth-child(4)::after { background: linear-gradient(135deg, rgba(225, 0, 255, 0.06), transparent); }
.interest-card:nth-child(5)::after { background: linear-gradient(135deg, rgba(79, 172, 254, 0.06), transparent); }
.interest-card:nth-child(6)::after { background: linear-gradient(135deg, rgba(255, 183, 77, 0.06), transparent); }
.interest-card:nth-child(7)::after { background: linear-gradient(135deg, rgba(255, 82, 82, 0.06), transparent); }

.interest-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-glass-hover);
  box-shadow: var(--shadow-card);
}

.interest-card:hover::after {
  opacity: 1;
}

.interest-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  border-radius: var(--radius-md);
  position: relative;
  z-index: 1;
}

.interest-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  position: relative;
  z-index: 1;
}

.interest-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.7;
  position: relative;
  z-index: 1;
}

/* ============================
   FOOTER
   ============================ */
.footer {
  text-align: center;
  padding: 2rem;
  border-top: 1px solid var(--border-glass);
  position: relative;
  z-index: 1;
}

.footer p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer a {
  color: var(--accent-cyan);
}

/* Page Bottom Actions (Sub-pages) */
.page-bottom-actions {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  margin-top: 4rem;
  margin-bottom: 2rem;
  padding: 2rem 0;
  border-top: 1px dashed var(--border-glass);
}

/* Scroll to Top Button */
.scroll-top-btn {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 46px;
  height: 46px;
  border-radius: var(--radius-full);
  background: rgba(13, 19, 33, 0.8);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--border-glass);
  color: var(--accent-cyan);
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-base);
  opacity: 0;
  pointer-events: none;
  transform: translateY(15px);
  z-index: 999;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.scroll-top-btn.show {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.scroll-top-btn:hover {
  background: var(--accent-cyan);
  color: var(--bg-primary);
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-glow-cyan);
  transform: translateY(-3px);
}

/* ============================
   SCROLL REVEAL
   ============================ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(25px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============================
   RESPONSIVE
   ============================ */
@media (max-width: 900px) {
  .hero-inner {
    flex-direction: column-reverse;
    text-align: center;
    gap: 2rem;
  }

  .hero-cta {
    justify-content: center;
  }

  .hero-contact-row {
    justify-content: center;
  }

  .profile-frame {
    width: 200px;
    height: 260px;
  }

  .cert-expand-inner {
    grid-template-columns: 1fr;
  }

  .cert-thumb-wrap {
    display: none;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    flex-direction: column;
    background: rgba(8, 12, 20, 0.95);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    border-bottom: 1px solid var(--border-glass);
    padding: 1rem;
    gap: 0.3rem;
  }

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

  .nav-toggle {
    display: flex;
  }

  .section {
    padding: 3rem 1.2rem;
  }

  .hero {
    padding: 1.5rem 1.2rem;
  }

  .skills-grid {
    grid-template-columns: 1fr;
  }

  .soft-skills-grid {
    grid-template-columns: 1fr;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }

  .cert-preview-grid {
    grid-template-columns: 1fr;
  }

  .interests-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .interests-grid {
    grid-template-columns: 1fr;
  }

  .hero-name {
    font-size: 2rem;
  }
}

.nav-links i {
  margin-right: 6px;
  font-size: 0.95rem;
  color: var(--accent-cyan);
  transition: color 0.3s ease;
}

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