/* ============================================
   Roger S. Mission — Personal Portfolio
   Clean, Minimalist, Professional Design
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700;800;900&display=swap');

/* ---------- CSS Variables ---------- */
:root {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #fafbfd;
  --bg-section-alt: #f1f5f9;
  --bg-hero: linear-gradient(160deg, #0f172a 0%, #1e3a5f 50%, #1a365d 100%);

  --border-light: #e2e8f0;
  --border-hover: #cbd5e1;

  --text-primary: #0f172a;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --text-on-dark: #f1f5f9;

  --accent-primary: #1e3a5f;
  --accent-blue: #2563eb;
  --accent-blue-soft: rgba(37, 99, 235, 0.08);
  --accent-blue-hover: #1d4ed8;
  --accent-sky: #0ea5e9;
  --accent-sky-soft: rgba(14, 165, 233, 0.08);
  --accent-gradient: linear-gradient(135deg, #2563eb, #0ea5e9);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.08), 0 4px 8px rgba(0,0,0,0.04);
  --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 4px 16px rgba(0,0,0,0.03);
  --shadow-card-hover: 0 8px 30px rgba(0,0,0,0.1), 0 2px 6px rgba(0,0,0,0.04);

  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #94a3b8; }

/* ---------- Animations ---------- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(5deg); }
}

@keyframes floatReverse {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(15px) rotate(-5deg); }
}

@keyframes pulse-glow {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(14, 165, 233, 0.4); }
  50% { opacity: 0.8; box-shadow: 0 0 0 8px rgba(14, 165, 233, 0); }
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.spin { animation: spin 1s linear infinite; }

/* Scroll Reveal */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease-out, transform 0.7s ease-out;
}

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

/* ---------- Navigation ---------- */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  padding: 0 2rem;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition-smooth);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: var(--shadow-sm);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-brand-icon {
  width: 38px;
  height: 38px;
  background: var(--accent-gradient);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 0.85rem;
  color: #fff;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
}

.nav-brand-text {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--accent-primary);
  line-height: 1.1;
}

.nav-brand-text span {
  color: var(--accent-blue);
  font-weight: 500;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition-fast);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0; right: 0;
  height: 2px;
  background: var(--accent-blue);
  border-radius: 1px;
  transform: scaleX(0);
  transition: transform var(--transition-fast);
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
}

.nav-cta {
  padding: 9px 22px !important;
  background: var(--accent-gradient) !important;
  border-radius: var(--radius-xl) !important;
  font-weight: 600 !important;
  font-size: 0.84rem !important;
  color: #fff !important;
  transition: var(--transition-fast);
  box-shadow: 0 2px 10px rgba(37, 99, 235, 0.25);
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 18px rgba(37, 99, 235, 0.35);
}

.nav-cta::after { display: none !important; }

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

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition-fast);
}

/* ---------- Hero Section ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 110px 2rem 80px;
  position: relative;
  overflow: hidden;
  background: var(--bg-hero);
}

.hero-bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
}

/* Floating geometric shapes */
.hero-shape {
  position: absolute;
  border-radius: 16px;
  opacity: 0.08;
}

.hero-shape-1 {
  width: 300px; height: 300px;
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
  top: 10%; left: -5%;
  transform: rotate(15deg);
  animation: float 8s ease-in-out infinite;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
}

.hero-shape-2 {
  width: 200px; height: 200px;
  background: linear-gradient(135deg, #06b6d4, #8b5cf6);
  bottom: 15%; right: 5%;
  transform: rotate(-10deg);
  animation: floatReverse 10s ease-in-out infinite;
  border-radius: 60% 40% 30% 70% / 60% 30% 70% 40%;
}

.hero-shape-3 {
  width: 150px; height: 150px;
  background: linear-gradient(135deg, #3b82f6, #10b981);
  top: 60%; left: 15%;
  animation: float 12s ease-in-out infinite;
  border-radius: 40% 60% 60% 40% / 50% 40% 60% 50%;
}

.hero-shape-4 {
  width: 100px; height: 100px;
  background: linear-gradient(135deg, #f59e0b, #ef4444);
  top: 20%; right: 15%;
  animation: floatReverse 9s ease-in-out infinite;
  border-radius: 50%;
}

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

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 18px;
  background: rgba(14, 165, 233, 0.12);
  border: 1px solid rgba(14, 165, 233, 0.25);
  border-radius: var(--radius-xl);
  font-size: 0.82rem;
  font-weight: 600;
  color: #7dd3fc;
  margin-bottom: 2rem;
  animation: fadeInUp 0.8s ease-out;
}

.badge-dot {
  width: 8px; height: 8px;
  background: #22d3ee;
  border-radius: 50%;
  animation: pulse-glow 2s infinite;
}

.hero h1 {
  font-size: clamp(2.4rem, 5.5vw, 4.2rem);
  font-weight: 900;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  color: #fff;
  animation: fadeInUp 0.8s ease-out 0.1s both;
}

.hero h1 .gradient-text {
  background: linear-gradient(135deg, #38bdf8, #818cf8, #c084fc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-credential {
  font-size: 0.6em;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.5);
  -webkit-text-fill-color: rgba(255, 255, 255, 0.5);
}

.hero-tagline {
  font-family: 'Outfit', sans-serif;
  font-size: clamp(1.1rem, 2.5vw, 1.5rem);
  font-weight: 600;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 1.5rem;
  letter-spacing: 0.03em;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-tagline .divider {
  color: rgba(255, 255, 255, 0.25);
  margin: 0 0.5rem;
}

.hero-subtitle {
  font-size: clamp(0.95rem, 1.8vw, 1.1rem);
  color: rgba(255, 255, 255, 0.55);
  max-width: 600px;
  margin: 0 auto 2.5rem;
  line-height: 1.7;
  animation: fadeInUp 0.8s ease-out 0.3s both;
}

.hero-subtitle strong {
  color: rgba(255, 255, 255, 0.85);
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: var(--radius-xl);
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 0.92rem;
  border: none;
  cursor: pointer;
  transition: var(--transition-fast);
}

.btn-primary {
  background: var(--accent-gradient);
  color: #fff;
  box-shadow: 0 3px 14px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 24px rgba(37, 99, 235, 0.4);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

/* Button variants on light backgrounds */
.about-section .btn-secondary,
.portfolio-section .btn-secondary,
.publications-section .btn-secondary,
.contact-section .btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-xs);
  backdrop-filter: none;
}

.about-section .btn-secondary:hover,
.portfolio-section .btn-secondary:hover,
.publications-section .btn-secondary:hover,
.contact-section .btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  color: var(--text-primary);
}

/* ---------- Section Styles ---------- */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent-blue);
  margin-bottom: 0.75rem;
}

.section-tag::before,
.section-tag::after {
  content: '';
  width: 20px;
  height: 1.5px;
  background: var(--accent-blue);
  opacity: 0.3;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin-bottom: 0.75rem;
}

.section-subtitle {
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
  font-size: 1rem;
}

/* ---------- About Section ---------- */
.about-section {
  background: var(--bg-primary);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.about-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  text-align: center;
  transition: var(--transition-smooth);
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.about-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--accent-gradient);
  transform: scaleX(0);
  transition: transform var(--transition-smooth);
}

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

.about-card:hover::before {
  transform: scaleX(1);
}

.about-card-icon {
  width: 56px;
  height: 56px;
  background: var(--accent-blue-soft);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  color: var(--accent-blue);
  transition: var(--transition-smooth);
}

.about-card:hover .about-card-icon {
  background: var(--accent-gradient);
  color: #fff;
}

.about-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
}

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

/* Skills */
.skills-section {
  text-align: center;
}

.skills-heading {
  font-size: 1.1rem;
  color: var(--text-secondary);
  font-weight: 600;
  margin-bottom: 1.5rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.skills-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
}

.skill-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 18px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-primary);
  transition: var(--transition-fast);
  box-shadow: var(--shadow-xs);
}

.skill-badge:hover {
  border-color: var(--accent-blue);
  background: var(--accent-blue-soft);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.skill-icon {
  font-size: 1rem;
}

/* ---------- Portfolio Section ---------- */
.portfolio-section {
  background: var(--bg-section-alt);
}

.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.portfolio-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition-smooth);
  box-shadow: var(--shadow-card);
}

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

/* Browser Device Mockup */
.device-mockup {
  position: relative;
  overflow: hidden;
}

.browser-frame {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  background: #f1f5f9;
  border-bottom: 1px solid var(--border-light);
}

.browser-dots {
  display: flex;
  gap: 5px;
}

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

.browser-dots span:nth-child(1) { background: #ef4444; }
.browser-dots span:nth-child(2) { background: #f59e0b; }
.browser-dots span:nth-child(3) { background: #22c55e; }

.browser-url {
  flex: 1;
  padding: 5px 12px;
  background: #fff;
  border: 1px solid var(--border-light);
  border-radius: 6px;
  font-size: 0.72rem;
  color: var(--text-muted);
  font-family: 'Inter', monospace;
}

.browser-screen {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: #e2e8f0;
}

.browser-screen img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.portfolio-card:hover .browser-screen img {
  transform: scale(1.05);
}

.portfolio-info {
  padding: 1.5rem 1.75rem 1.75rem;
}

.portfolio-info h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

.portfolio-info p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1rem;
}

.portfolio-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 1rem;
}

.portfolio-tags span {
  padding: 4px 12px;
  background: var(--accent-blue-soft);
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent-blue);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.portfolio-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent-blue);
  transition: var(--transition-fast);
}

.portfolio-link:hover {
  color: var(--accent-blue-hover);
  gap: 10px;
}

/* ---------- Publications Section ---------- */
.publications-section {
  background: var(--bg-primary);
}

.publications-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.pub-card {
  display: flex;
  gap: 1.25rem;
  padding: 1.75rem;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  transition: var(--transition-smooth);
  box-shadow: var(--shadow-card);
}

.pub-card:hover {
  border-color: var(--accent-blue);
  transform: translateX(6px);
  box-shadow: var(--shadow-card-hover);
}

.pub-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  background: var(--accent-blue-soft);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-blue);
  transition: var(--transition-smooth);
}

.pub-card:hover .pub-icon {
  background: var(--accent-gradient);
  color: #fff;
}

.pub-content h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
  line-height: 1.4;
}

.pub-meta {
  font-size: 0.78rem;
  color: var(--accent-blue);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.pub-abstract {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.scholar-cta {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 3rem;
  flex-wrap: wrap;
}

.btn-scholar {
  padding: 14px 32px;
}

/* ---------- Contact Section ---------- */
.contact-section {
  background: var(--bg-section-alt);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 2rem;
  max-width: 900px;
  margin: 0 auto;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-info-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  transition: var(--transition-smooth);
  box-shadow: var(--shadow-xs);
}

.contact-info-card:hover {
  border-color: var(--border-hover);
  box-shadow: var(--shadow-sm);
}

.contact-icon {
  width: 44px;
  height: 44px;
  background: var(--accent-blue-soft);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-blue);
  flex-shrink: 0;
}

.contact-info-card h4 {
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 2px;
}

.contact-info-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.contact-socials {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.social-link {
  width: 44px;
  height: 44px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: var(--transition-fast);
  box-shadow: var(--shadow-xs);
}

.social-link:hover {
  background: var(--accent-gradient);
  border-color: transparent;
  color: #fff;
  transform: translateY(-3px);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

/* Contact Form */
.contact-form-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-card);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 5px;
  margin-bottom: 1rem;
}

.form-group label {
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-input,
.form-textarea {
  padding: 11px 14px;
  background: var(--bg-primary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: 'Inter', sans-serif;
  font-size: 0.9rem;
  transition: var(--transition-fast);
  outline: none;
}

.form-input:focus,
.form-textarea:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  background: #fff;
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--text-muted);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

.btn-submit {
  width: 100%;
  justify-content: center;
  padding: 14px;
  margin-top: 0.5rem;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--accent-primary);
  padding: 3rem 0;
}

.footer-content {
  text-align: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 1.5rem;
}

.footer-logo {
  width: 36px;
  height: 36px;
  background: var(--accent-gradient);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 0.8rem;
  color: #fff;
}

.footer-brand span {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  color: #fff;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  list-style: none;
  margin-bottom: 1.5rem;
}

.footer-links a {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  transition: var(--transition-fast);
}

.footer-links a:hover {
  color: #fff;
}

.footer-copy {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.35);
}

/* ---------- Toast ---------- */
.toast {
  position: fixed;
  bottom: 30px;
  right: 30px;
  padding: 14px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.88rem;
  font-weight: 500;
  transform: translateY(100px);
  opacity: 0;
  transition: var(--transition-spring);
  z-index: 9999;
}

.toast.show {
  transform: translateY(0);
  opacity: 1;
}

.toast.error {
  border-color: rgba(220, 38, 38, 0.3);
  background: #fef2f2;
}

/* ---------- Education Timeline ---------- */
.education-section {
  background: var(--bg-primary);
}

.edu-timeline {
  position: relative;
  max-width: 700px;
  margin: 0 auto;
  padding-left: 2rem;
}

.edu-timeline::before {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 2px;
  background: var(--accent-blue-soft);
  border-radius: 1px;
}

.edu-item {
  position: relative;
  padding-bottom: 2.25rem;
}

.edu-item:last-child {
  padding-bottom: 0;
}

.edu-dot {
  position: absolute;
  left: calc(-2rem - 7px);
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent-gradient);
  box-shadow: 0 0 0 4px var(--bg-primary);
  z-index: 1;
}

.edu-year {
  display: inline-block;
  padding: 3px 12px;
  background: var(--accent-blue-soft);
  color: var(--accent-blue);
  font-size: 0.75rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  margin-bottom: 0.5rem;
}

.edu-school {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.edu-degree {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 0.25rem;
}

.edu-scholarship {
  font-size: 0.82rem;
  font-style: italic;
  color: var(--text-muted);
}

/* ---------- Affiliations Section ---------- */
.affiliations-section {
  background: var(--bg-section-alt);
}

.affiliations-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  max-width: 900px;
  margin: 0 auto;
}

.affiliation-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-left: 3px solid transparent;
  border-radius: var(--radius-md);
  padding: 1.5rem 1.75rem;
  box-shadow: var(--shadow-card);
  transition: var(--transition-smooth);
}

.affiliation-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
  border-left: 3px solid;
  border-image: var(--accent-gradient) 1;
}

.affiliation-role {
  display: block;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-blue);
  margin-bottom: 0.35rem;
}

.affiliation-org {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.3rem;
}

.affiliation-period {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ---------- Memberships Section ---------- */
.memberships-section {
  background: var(--bg-primary);
}

.memberships-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
}

.membership-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 14px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-primary);
  transition: var(--transition-fast);
  box-shadow: var(--shadow-xs);
  max-width: 320px;
}

.membership-card h4 {
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.4;
}

.membership-card:hover {
  border-color: var(--accent-blue);
  background: var(--accent-blue-soft);
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
}

.membership-role {
  display: block;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ---------- Academic IDs Bar ---------- */
.academic-ids {
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.academic-id {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  border-bottom: 1px dashed var(--border-light);
  padding-bottom: 2px;
}

.academic-id-label {
  font-weight: 600;
  color: var(--text-primary);
}

.academic-id-value {
  font-family: 'Courier New', Courier, monospace;
  color: var(--text-muted);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 1024px) {
  .about-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .about-card:last-child {
    grid-column: 1 / -1;
    max-width: 500px;
    margin: 0 auto;
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: 0 1.25rem;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 68px;
    left: 0; right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    flex-direction: column;
    padding: 1.5rem 2rem 2rem;
    gap: 1rem;
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-lg);
    transform: translateY(-120%);
    opacity: 0;
    transition: var(--transition-smooth);
    pointer-events: none;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-cta {
    text-align: center;
    display: block !important;
    padding: 12px 22px !important;
  }

  .hero {
    padding: 100px 1.25rem 60px;
    min-height: 80vh;
  }

  .hero h1 {
    font-size: clamp(2rem, 7vw, 2.8rem);
  }

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

  .about-card:last-child {
    max-width: 100%;
  }

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

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

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

  .edu-timeline {
    padding-left: 1.5rem;
  }

  .pub-card {
    flex-direction: column;
    align-items: flex-start;
  }

  .scholar-cta {
    flex-direction: column;
    align-items: center;
  }

  .footer-links {
    flex-wrap: wrap;
    gap: 1rem 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .contact-socials {
    justify-content: center;
  }

  .section {
    padding: 60px 0;
  }

  .hero {
    padding: 90px 1rem 50px;
  }

  .portfolio-info {
    padding: 1.25rem;
  }

  .pub-card {
    padding: 1.25rem;
  }

  .academic-ids {
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
  }

  .contact-form-card {
    padding: 1.5rem;
  }
}