/* ============================================
   MEHRAN MAZHAR — PORTFOLIO
   Modern Dark Theme with Glass-morphism
   ============================================ */

/* ---------- CSS Custom Properties ---------- */
:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-secondary: #111119;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-card-hover: rgba(255, 255, 255, 0.06);
  --bg-glass: rgba(17, 17, 25, 0.7);

  --text-primary: #f0f0f5;
  --text-secondary: #a0a0b8;
  --text-muted: #6b6b80;

  --accent-primary: #6366f1;
  --accent-secondary: #8b5cf6;
  --accent-tertiary: #06b6d4;
  --accent-gradient: linear-gradient(135deg, #6366f1, #8b5cf6, #06b6d4);

  --border-color: rgba(255, 255, 255, 0.06);
  --border-color-hover: rgba(255, 255, 255, 0.12);

  /* Spacing */
  --section-padding: 120px;
  --container-max: 1100px;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Transitions */
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
  font-size: 16px;
}

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

::selection {
  background: rgba(99, 102, 241, 0.3);
  color: var(--text-primary);
}

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

a:hover {
  color: var(--accent-tertiary);
}

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

mark {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.25), rgba(6, 182, 212, 0.25));
  color: var(--accent-tertiary);
  padding: 2px 8px;
  border-radius: 4px;
}

strong {
  color: var(--text-primary);
  font-weight: 600;
}

/* ---------- Container ---------- */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Section ---------- */
.section {
  padding: var(--section-padding) 0;
  position: relative;
}

.section__title {
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  font-weight: 700;
  margin-bottom: 60px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.section__title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-color);
  max-width: 300px;
}

.section__number {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  color: var(--accent-primary);
}

.section__subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin-top: -40px;
  margin-bottom: 48px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-base);
  border: 1px solid transparent;
  text-decoration: none;
  white-space: nowrap;
}

.btn--primary {
  background: var(--accent-gradient);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.25);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(99, 102, 241, 0.35);
  color: #fff;
}

.btn--outline {
  background: transparent;
  color: var(--accent-primary);
  border-color: var(--accent-primary);
}

.btn--outline:hover {
  background: rgba(99, 102, 241, 0.1);
  transform: translateY(-2px);
  color: var(--accent-primary);
}

.btn--sm {
  padding: 10px 20px;
  font-size: 0.875rem;
}

.btn--lg {
  padding: 18px 36px;
  font-size: 1.05rem;
}

/* ============================================
   NAVIGATION
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all var(--transition-base);
}

.nav--scrolled {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  padding: 12px 0;
}

.nav__container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.nav__logo:hover {
  color: var(--text-primary);
}

.nav__logo-bracket {
  color: var(--accent-primary);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
}

.nav__link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  text-decoration: none;
}

.nav__link:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.nav__link--cta {
  background: var(--accent-gradient);
  color: #fff !important;
  padding: 8px 20px;
}

.nav__link--cta:hover {
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.3);
}

/* Mobile Toggle */
.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 1001;
}

.nav__toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.nav__toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav__toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav__toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}

.hero__bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 60% 60% at 50% 40%, black 20%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 60% 60% at 50% 40%, black 20%, transparent 70%);
}

.hero__glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.15;
  pointer-events: none;
}

.hero__glow--1 {
  width: 600px;
  height: 600px;
  background: var(--accent-primary);
  top: -200px;
  right: -100px;
  animation: glowFloat 8s ease-in-out infinite;
}

.hero__glow--2 {
  width: 400px;
  height: 400px;
  background: var(--accent-tertiary);
  bottom: -100px;
  left: -100px;
  animation: glowFloat 10s ease-in-out infinite reverse;
}

@keyframes glowFloat {
  0%, 100% { transform: translate(0, 0); }
  33% { transform: translate(30px, -20px); }
  66% { transform: translate(-20px, 20px); }
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero__greeting {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--accent-primary);
  margin-bottom: 16px;
  font-weight: 500;
}

.hero__name {
  font-size: clamp(2.8rem, 7vw, 4.5rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -2px;
  margin-bottom: 12px;
}

.hero__title {
  font-size: clamp(1.3rem, 3.5vw, 2rem);
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 24px;
  line-height: 1.3;
}

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

.hero__description {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 36px;
  max-width: 580px;
}

.hero__actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

.hero__tech {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.hero__tech-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.hero__tech-icons {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tech-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 6px 14px;
  border-radius: 100px;
  background: rgba(99, 102, 241, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(99, 102, 241, 0.15);
  transition: all var(--transition-fast);
}

.tech-pill:hover {
  background: rgba(99, 102, 241, 0.2);
  border-color: rgba(99, 102, 241, 0.3);
}

/* Hero Scroll Indicator */
.hero__scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
}

.hero__scroll-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  text-decoration: none;
  animation: scrollBounce 2s infinite;
}

.hero__scroll-link:hover {
  color: var(--accent-primary);
}

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

/* ============================================
   ABOUT SECTION
   ============================================ */
.about__grid {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 60px;
  align-items: start;
}

.about__image-wrapper {
  position: relative;
  width: 280px;
  height: 320px;
}

.about__image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius-md);
  position: relative;
  z-index: 1;
  filter: grayscale(20%);
  transition: filter var(--transition-base);
}

.about__image-wrapper:hover .about__image {
  filter: grayscale(0%);
}

.about__image-border {
  position: absolute;
  top: 16px;
  left: 16px;
  width: 100%;
  height: 100%;
  border: 2px solid var(--accent-primary);
  border-radius: var(--radius-md);
  opacity: 0.4;
  transition: all var(--transition-base);
}

.about__image-wrapper:hover .about__image-border {
  top: 12px;
  left: 12px;
  opacity: 0.6;
}

.about__text p {
  color: var(--text-secondary);
  margin-bottom: 20px;
  font-size: 1.02rem;
}

.about__skills {
  margin-top: 32px;
}

.about__skills h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.about__skill-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.skill-card {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  cursor: default;
}

.skill-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-color-hover);
  transform: translateY(-2px);
}

.skill-card i {
  color: var(--accent-primary);
  font-size: 0.95rem;
  width: 20px;
  text-align: center;
}

.skill-card span {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
}

/* ============================================
   PROJECTS SECTION
   ============================================ */
.project-featured__header {
  margin-bottom: 32px;
}

.project-featured__label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-primary);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 8px;
  display: block;
}

.project-featured__title {
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 4px;
}

.project-featured__subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
}

.project-featured__card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
}

.project-featured__quote {
  font-size: 1.15rem;
  color: var(--text-secondary);
  font-style: italic;
  padding-left: 20px;
  border-left: 3px solid var(--accent-primary);
  margin-bottom: 28px;
  line-height: 1.8;
}

.project-featured__description p {
  color: var(--text-secondary);
  margin-bottom: 28px;
}

/* Repository Cards */
.project-featured__repos {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 36px;
}

.repo-card {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 20px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: all var(--transition-base);
  position: relative;
}

.repo-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-primary);
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(99, 102, 241, 0.1);
  color: inherit;
}

.repo-card__icon {
  font-size: 1.4rem;
  color: var(--text-muted);
  margin-top: 2px;
  flex-shrink: 0;
}

.repo-card__content h4 {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.repo-card__content p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 10px;
}

.repo-card__tech {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.repo-card__tech span {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 3px 10px;
  background: rgba(99, 102, 241, 0.08);
  color: var(--accent-primary);
  border-radius: 100px;
}

.repo-card__arrow {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 0.75rem;
  color: var(--text-muted);
  opacity: 0;
  transform: translate(-4px, 4px);
  transition: all var(--transition-base);
}

.repo-card:hover .repo-card__arrow {
  opacity: 1;
  transform: translate(0, 0);
  color: var(--accent-primary);
}

/* Stats */
.project-featured__stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}

.stat {
  text-align: center;
  padding: 24px 16px;
  background: rgba(99, 102, 241, 0.05);
  border: 1px solid rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-md);
}

.stat__value {
  display: block;
  font-size: 1.6rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 4px;
}

.stat__label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 2px;
}

.stat__note {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.project-featured__cta {
  text-align: center;
}

/* ============================================
   EXPERIENCE (TIMELINE)
   ============================================ */
.timeline {
  position: relative;
  padding-left: 40px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-primary), transparent);
}

.timeline__item {
  position: relative;
  margin-bottom: 48px;
}

.timeline__item:last-child {
  margin-bottom: 0;
}

.timeline__dot {
  position: absolute;
  left: -40px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 2px solid var(--accent-primary);
  box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.15);
}

.timeline__content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition-base);
}

.timeline__content:hover {
  border-color: var(--border-color-hover);
}

.timeline__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 12px;
}

.timeline__role {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.timeline__company {
  font-size: 0.95rem;
  color: var(--accent-primary);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.timeline__company i {
  font-size: 0.7rem;
}

.timeline__date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  padding: 4px 12px;
  background: rgba(99, 102, 241, 0.08);
  border-radius: 100px;
  white-space: nowrap;
}

.timeline__quote {
  font-style: italic;
  color: var(--text-secondary);
  margin-bottom: 20px;
  padding-left: 16px;
  border-left: 2px solid var(--accent-primary);
  line-height: 1.8;
}

.timeline__list {
  list-style: none;
  margin-bottom: 20px;
}

.timeline__list li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 12px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.timeline__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-primary);
}

.timeline__tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.timeline__tags span {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 4px 12px;
  background: rgba(99, 102, 241, 0.08);
  color: var(--accent-primary);
  border-radius: 100px;
}

/* ============================================
   RESEARCH SECTION
   ============================================ */
.research__card {
  display: flex;
  gap: 40px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 48px;
}

.research__icon {
  flex-shrink: 0;
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-md);
  font-size: 1.6rem;
  color: var(--accent-primary);
}

.research__label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-primary);
  text-transform: uppercase;
  letter-spacing: 2px;
  display: block;
  margin-bottom: 8px;
}

.research__title {
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 8px;
}

.research__advisor {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.research__quote {
  color: var(--text-secondary);
  font-style: italic;
  padding-left: 16px;
  border-left: 2px solid var(--accent-primary);
  margin-bottom: 28px;
  line-height: 1.8;
}

.research__highlights {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.research__highlight {
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.research__highlight i {
  color: var(--accent-primary);
  font-size: 1rem;
  margin-top: 4px;
  width: 20px;
  text-align: center;
  flex-shrink: 0;
}

.research__highlight strong {
  display: block;
  font-size: 0.9rem;
  margin-bottom: 2px;
}

.research__highlight p {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.research__note {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-style: italic;
  margin-bottom: 24px;
  padding: 16px;
  background: rgba(99, 102, 241, 0.05);
  border-radius: var(--radius-sm);
}

.research__actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* ============================================
   INTERESTS SECTION
   ============================================ */
.interests__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.interest-card {
  padding: 32px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: all var(--transition-base);
}

.interest-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent-primary);
  box-shadow: 0 12px 40px rgba(99, 102, 241, 0.1);
}

.interest-card__icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-md);
  font-size: 1.4rem;
  color: var(--accent-primary);
  transition: all var(--transition-base);
}

.interest-card:hover .interest-card__icon {
  background: var(--accent-gradient);
  color: #fff;
  transform: scale(1.1);
}

.interest-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.interest-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ============================================
   CONTACT / CTA SECTION
   ============================================ */
.contact {
  padding: 100px 0;
}

.contact__content {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

.contact__label {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent-primary);
  display: block;
  margin-bottom: 16px;
}

.contact__title {
  font-size: clamp(2rem, 5vw, 2.8rem);
  font-weight: 800;
  margin-bottom: 20px;
  line-height: 1.2;
}

.contact__text {
  color: var(--text-secondary);
  font-size: 1.05rem;
  margin-bottom: 36px;
  line-height: 1.8;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  padding: 40px 0;
  border-top: 1px solid var(--border-color);
  text-align: center;
}

.footer__social {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 24px;
}

.footer__social-link {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 1.1rem;
  transition: all var(--transition-base);
  text-decoration: none;
}

.footer__social-link:hover {
  background: var(--accent-gradient);
  border-color: transparent;
  color: #fff;
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.25);
}

.footer__credit {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.footer__copyright {
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ============================================
   SCROLL REVEAL ANIMATIONS
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

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

/* Stagger children */
.reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal:nth-child(3) { transition-delay: 0.2s; }
.reveal:nth-child(4) { transition-delay: 0.3s; }
.reveal:nth-child(5) { transition-delay: 0.4s; }

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

/* Tablet */
@media (max-width: 1024px) {
  :root {
    --section-padding: 80px;
  }

  .about__grid {
    grid-template-columns: 220px 1fr;
    gap: 40px;
  }

  .about__image-wrapper {
    width: 220px;
    height: 260px;
  }

  .about__skill-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .project-featured__repos {
    grid-template-columns: 1fr;
  }

  .project-featured__stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .interests__grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

/* Mobile */
@media (max-width: 768px) {
  :root {
    --section-padding: 64px;
  }

  html {
    font-size: 15px;
  }

  .nav__toggle {
    display: flex;
  }

  .nav__links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--bg-secondary);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 4px;
    border-left: 1px solid var(--border-color);
    transition: right var(--transition-base);
    z-index: 1000;
  }

  .nav__links.open {
    right: 0;
  }

  .nav__link {
    font-size: 1rem;
    padding: 12px 24px;
    width: 100%;
    text-align: center;
  }

  .hero__name {
    letter-spacing: -1px;
  }

  .about__grid {
    grid-template-columns: 1fr;
    gap: 32px;
    text-align: center;
  }

  .about__image-wrapper {
    width: 200px;
    height: 240px;
    margin: 0 auto;
  }

  .about__skills {
    text-align: left;
  }

  .about__skill-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .section__title {
    margin-bottom: 40px;
  }

  .section__title::after {
    max-width: 120px;
  }

  .project-featured__card {
    padding: 24px;
  }

  .project-featured__stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .stat {
    padding: 16px 12px;
  }

  .stat__value {
    font-size: 1.3rem;
  }

  .timeline {
    padding-left: 28px;
  }

  .timeline__dot {
    left: -28px;
    width: 12px;
    height: 12px;
  }

  .timeline::before {
    left: 5px;
  }

  .timeline__content {
    padding: 24px;
  }

  .timeline__header {
    flex-direction: column;
  }

  .research__card {
    flex-direction: column;
    padding: 28px;
    gap: 20px;
  }

  .research__icon {
    width: 52px;
    height: 52px;
    font-size: 1.3rem;
  }

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

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

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

  .research__actions {
    flex-direction: column;
  }

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

/* Small Mobile */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

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

  .project-featured__stats {
    grid-template-columns: 1fr;
  }

  .footer__social {
    gap: 12px;
  }
}

/* ---------- Accessibility ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* Focus styles */
:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 4px;
  border-radius: 4px;
}