/* ============================================
   Custom Properties
   ============================================ */
:root {
  --color-bg: #fafafa;
  --color-text: #1a1a1a;
  --color-accent: #2563eb;
  --color-accent-light: #3b82f6;
  --color-muted: #6b7280;
  --color-card: #ffffff;
  --color-border: #e5e7eb;
  --color-card-shadow: rgba(0, 0, 0, 0.06);
  --color-section-alt: #f3f4f6;
  --color-languages: #2563eb;
  --color-languages-bg: #eff6ff;
  --color-languages-border: #bfdbfe;
  --color-frameworks: #7c3aed;
  --color-frameworks-bg: #f5f3ff;
  --color-frameworks-border: #c4b5fd;
  --color-cloud: #059669;
  --color-cloud-bg: #ecfdf5;
  --color-cloud-border: #a7f3d0;
  --color-tools: #d97706;
  --color-tools-bg: #fffbeb;
  --color-tools-border: #fcd34d;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --nav-height: 64px;
  --container-max: 1120px;
  --section-padding: 120px;
  --transition: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

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

.section {
  padding: var(--section-padding) 0;
}

.section--alt {
  background: var(--color-section-alt);
}

.section--gradient-subtle {
  background: linear-gradient(180deg, var(--color-bg) 0%, rgba(37, 99, 235, 0.03) 50%, var(--color-bg) 100%);
}

.section--gradient-bottom {
  background: linear-gradient(180deg, var(--color-bg) 0%, rgba(139, 92, 246, 0.04) 100%);
}

.section__title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 60px;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--color-text) 0%, #374151 50%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: inline-block;
}

/* ============================================
   Navigation
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  transition: background var(--transition), box-shadow var(--transition);
}

.nav--scrolled {
  background: rgba(250, 250, 250, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--color-border);
  border-bottom: 1px solid transparent;
  border-image: linear-gradient(90deg, transparent, rgba(37, 99, 235, 0.15), rgba(139, 92, 246, 0.15), transparent) 1;
}

.nav__container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--color-accent), #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav__logo:hover {
  background: linear-gradient(135deg, #8b5cf6, #ec4899);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav__links {
  display: flex;
  gap: 32px;
}

.nav__links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-muted);
  transition: color var(--transition);
}

.nav__links a:hover {
  color: var(--color-text);
}

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

.nav__toggle span {
  width: 20px;
  height: 2px;
  background: var(--color-text);
  transition: transform var(--transition), opacity var(--transition);
}

.nav__toggle--active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

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

.nav__toggle--active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ============================================
   Hero
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: var(--nav-height) 24px 0;
  background: radial-gradient(ellipse at 20% 50%, rgba(37, 99, 235, 0.06) 0%, transparent 50%),
              radial-gradient(ellipse at 80% 50%, rgba(139, 92, 246, 0.06) 0%, transparent 50%),
              var(--color-bg);
}

.hero__content {
  text-align: center;
}

.hero__greeting {
  font-size: 1rem;
  font-weight: 400;
  color: var(--color-muted);
  margin-bottom: 12px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hero__name {
  font-size: clamp(2.5rem, 7vw, 5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 20px;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-accent) 60%, #8b5cf6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__gradient-line {
  width: 160px;
  height: 4px;
  margin: 0 auto 24px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--color-accent), #8b5cf6, #ec4899, var(--color-accent));
  background-size: 300% 100%;
  animation: gradient-shift 4s ease infinite;
}

@keyframes gradient-shift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.hero__title {
  font-size: clamp(1.125rem, 2.5vw, 1.5rem);
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 8px;
}

.hero__subtitle {
  font-size: 1rem;
  color: var(--color-muted);
  font-weight: 400;
}

.hero__socials {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-top: 28px;
}

.hero__socials a {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1.5px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-muted);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.hero__socials a::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-accent), #8b5cf6);
  transform: scale(0);
  transition: transform 0.3s ease;
}

.hero__socials a:hover {
  border-color: transparent;
  color: #fff;
}

.hero__socials a:hover::before {
  transform: scale(1);
}

.hero__socials a svg {
  position: relative;
  z-index: 1;
}

.hero__scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.hero__scroll span {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.hero__scroll-line {
  width: 1px;
  height: 40px;
  background: var(--color-muted);
  position: relative;
  overflow: hidden;
}

.hero__scroll-line::after {
  content: '';
  position: absolute;
  top: -100%;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, var(--color-accent), #8b5cf6);
  animation: scroll-line 2s ease infinite;
}

@keyframes scroll-line {
  0% { top: -100%; }
  100% { top: 100%; }
}

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

.about__image {
  position: relative;
}

.about__image::after {
  content: '';
  position: absolute;
  inset: 12px -12px -12px 12px;
  border-radius: 16px;
  border: 2px solid var(--color-accent);
  opacity: 0.15;
  z-index: -1;
}

.about__image img {
  width: 280px;
  height: 280px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: 0 20px 40px var(--color-card-shadow);
  transition: transform var(--transition);
}

.about__image:hover img {
  transform: scale(1.02);
}

.about__text {
  font-size: 1.0625rem;
  color: var(--color-muted);
  margin-bottom: 16px;
  line-height: 1.7;
}

.about__stats {
  display: flex;
  gap: 40px;
  margin-top: 32px;
}

.about__stat {
  display: flex;
  flex-direction: column;
}

.about__stat-number {
  font-size: 2rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--color-accent), #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}

.about__stat-label {
  font-size: 0.8125rem;
  color: var(--color-muted);
  margin-top: 4px;
}

/* ============================================
   Experience Timeline
   ============================================ */
.timeline {
  position: relative;
  padding-left: 40px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--color-accent), var(--color-border) 40%);
}

.timeline__item {
  position: relative;
  padding-bottom: 48px;
  display: flex;
  align-items: flex-start;
  gap: 24px;
}

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

.timeline__content {
  flex: 1;
  min-width: 0;
}

.timeline__marker {
  position: absolute;
  left: -40px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 2px solid var(--color-border);
  transition: border-color var(--transition), background var(--transition);
}

.timeline__item:first-child .timeline__marker {
  border-color: var(--color-accent);
  background: var(--color-accent);
}

.timeline__date {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-accent);
  letter-spacing: 0.02em;
}

.timeline__role {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 4px;
  letter-spacing: -0.01em;
}

.timeline__company {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-top: 2px;
}

.timeline__description {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-top: 8px;
  line-height: 1.6;
  max-width: 560px;
}

.timeline__logo {
  width: 180px;
  height: 80px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 4px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  overflow: hidden;
  padding: 14px 20px;
  transition: transform var(--transition), box-shadow var(--transition);
}

.timeline__logo:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.timeline__logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

/* ============================================
   Skills
   ============================================ */
.skills__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.skills__category {
  background: var(--color-card);
  border-radius: 16px;
  padding: 32px;
  box-shadow: 0 1px 3px var(--color-card-shadow);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-border);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.skills__category:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 32px var(--color-card-shadow);
}

.skills__category--languages { border-left-color: var(--color-languages); }
.skills__category--frameworks { border-left-color: var(--color-frameworks); }
.skills__category--cloud { border-left-color: var(--color-cloud); }
.skills__category--tools { border-left-color: var(--color-tools); }

.skills__category-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.skills__icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.skills__category--languages .skills__icon {
  background: var(--color-languages-bg);
  color: var(--color-languages);
}

.skills__category--frameworks .skills__icon {
  background: var(--color-frameworks-bg);
  color: var(--color-frameworks);
}

.skills__category--cloud .skills__icon {
  background: var(--color-cloud-bg);
  color: var(--color-cloud);
}

.skills__category--tools .skills__icon {
  background: var(--color-tools-bg);
  color: var(--color-tools);
}

.skills__category-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

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

.skills__tag {
  font-size: 0.8125rem;
  font-weight: 500;
  padding: 6px 14px;
  border-radius: 100px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  cursor: default;
}

.skills__tag:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.08);
}

.skills__category--languages .skills__tag {
  background: var(--color-languages-bg);
  color: var(--color-languages);
  border: 1px solid var(--color-languages-border);
}

.skills__category--frameworks .skills__tag {
  background: var(--color-frameworks-bg);
  color: var(--color-frameworks);
  border: 1px solid var(--color-frameworks-border);
}

.skills__category--cloud .skills__tag {
  background: var(--color-cloud-bg);
  color: var(--color-cloud);
  border: 1px solid var(--color-cloud-border);
}

.skills__category--tools .skills__tag {
  background: var(--color-tools-bg);
  color: var(--color-tools);
  border: 1px solid var(--color-tools-border);
}

/* ============================================
   Projects
   ============================================ */
.projects__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.project-card {
  background: var(--color-card);
  border-radius: 16px;
  border: 1px solid var(--color-border);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
  position: relative;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent), #8b5cf6);
  opacity: 0;
  transition: opacity var(--transition);
}

.project-card:nth-child(1)::before { background: linear-gradient(90deg, #2563eb, #8b5cf6); }
.project-card:nth-child(2)::before { background: linear-gradient(90deg, #8b5cf6, #ec4899); }
.project-card:nth-child(3)::before { background: linear-gradient(90deg, #059669, #2563eb); }
.project-card:nth-child(4)::before { background: linear-gradient(90deg, #d97706, #ec4899); }

.project-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}

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

.project-card__content {
  padding: 32px;
}

.project-card__title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.project-card__description {
  font-size: 0.9375rem;
  color: var(--color-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}

.project-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
}

.project-card__tags span {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 4px 12px;
  border-radius: 100px;
  background: #eff6ff;
  color: var(--color-accent);
  border: 1px solid #bfdbfe;
}

.project-card__links {
  display: flex;
  gap: 16px;
}

.project-card__links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-accent);
  transition: color var(--transition);
}

.project-card__links a:hover {
  color: var(--color-accent-light);
}

/* ============================================
   Education
   ============================================ */
.education__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.education__card {
  background: var(--color-card);
  border-radius: 16px;
  padding: 28px;
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--color-accent);
  transition: transform var(--transition), box-shadow var(--transition);
}


.education__card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}

.education__year {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-accent);
}

.education__degree {
  font-size: 1.125rem;
  font-weight: 600;
  margin-top: 4px;
  letter-spacing: -0.01em;
}

.education__school {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-top: 2px;
}

.education__detail {
  font-size: 0.8125rem;
  color: var(--color-muted);
  margin-top: 6px;
  font-style: italic;
}

/* ============================================
   Contact
   ============================================ */
.contact {
  text-align: center;
}

.contact__subtitle {
  font-size: 1.0625rem;
  color: var(--color-muted);
  margin-bottom: 40px;
  margin-top: -40px;
}

.contact__links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 24px;
}

.contact__link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  background: var(--color-card);
  border-radius: 12px;
  border: 1px solid var(--color-border);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-muted);
  transition: transform var(--transition), box-shadow var(--transition), color var(--transition), border-color var(--transition);
}

.contact__link:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 24px rgba(37, 99, 235, 0.1);
  color: var(--color-accent);
  border-color: var(--color-accent-light);
}

.contact__link svg {
  flex-shrink: 0;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  padding: 32px 0;
  text-align: center;
  border-top: none;
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 200px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-accent), #8b5cf6, transparent);
  border-radius: 1px;
}

.footer p {
  font-size: 0.8125rem;
  color: var(--color-muted);
}

/* ============================================
   Animations
   ============================================ */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in--visible {
  opacity: 1;
  transform: translateY(0);
}

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

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
  .skills__grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --section-padding: 80px;
  }

  .section__title {
    font-size: 1.75rem;
    margin-bottom: 40px;
  }

  /* Nav mobile */
  .nav__toggle {
    display: flex;
  }

  .nav__links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(250, 250, 250, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    flex-direction: column;
    gap: 0;
    padding: 16px 24px;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition), opacity var(--transition);
  }

  .nav__links--open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav__links a {
    display: block;
    padding: 12px 0;
    font-size: 1rem;
  }

  /* Experience */
  .timeline__item {
    flex-wrap: wrap;
  }

  .timeline__logo {
    width: 140px;
    height: 64px;
    border-radius: 10px;
    padding: 10px 16px;
    order: -1;
    margin-top: 0;
    margin-bottom: 8px;
  }

  .timeline__content {
    width: 100%;
  }

  /* About */
  .about__grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .about__image {
    display: flex;
    justify-content: center;
  }

  .about__image::after {
    display: none;
  }

  .about__image img {
    width: 200px;
    height: 200px;
  }

  .about__stats {
    justify-content: center;
  }

  /* Skills */
  .skills__grid {
    grid-template-columns: 1fr;
  }

  /* Projects */
  .projects__grid {
    grid-template-columns: 1fr;
  }

  /* Education */
  .education__grid {
    grid-template-columns: 1fr;
  }

  /* Contact */
  .contact__links {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 480px) {
  .hero__name {
    font-size: 2.25rem;
  }

  .about__stats {
    gap: 24px;
  }

  .about__stat-number {
    font-size: 1.5rem;
  }
}