/* ===== CSS VARIABLES ===== */
:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafc;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-text: #0f172a;
  --color-text-muted: #64748b;
  --color-accent: #2563eb;
  --color-accent-dark: #1d4ed8;
  --color-accent-light: #eff6ff;
  --font-sans: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius: 0.75rem;
  --radius-sm: 0.375rem;
  --shadow-sm: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --nav-height: 64px;
  --transition: 0.2s ease;
}

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

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

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  font-size: 1rem;
}

img, svg { display: block; }

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

ul { list-style: none; }

/* ===== LAYOUT ===== */
.container {
  width: 100%;
  max-width: 1120px;
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.section {
  padding-block: 6rem;
}

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

/* ===== SECTION HEADER ===== */
.section__label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
}

.section__heading {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.section__sub {
  margin-top: 0.75rem;
  color: var(--color-text-muted);
  font-size: 1.0625rem;
  max-width: 52ch;
}

.section__header {
  margin-bottom: 3rem;
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition);
  border: 2px solid transparent;
  white-space: nowrap;
}

.btn--primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

.btn--primary:hover {
  background: var(--color-accent-dark);
  border-color: var(--color-accent-dark);
  box-shadow: var(--shadow-md);
}

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

.btn--outline:hover {
  background: var(--color-accent-light);
}

.btn--lg {
  padding: 0.875rem 2rem;
  font-size: 1rem;
}

/* ===== NAVIGATION ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
  transition: box-shadow var(--transition);
}

.nav.scrolled {
  box-shadow: var(--shadow-sm);
}

.nav__inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-family: var(--font-mono);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: -0.01em;
  transition: opacity var(--transition);
}

.nav__logo:hover { opacity: 0.8; }

.nav__links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav__links a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition);
  position: relative;
}

.nav__links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition);
}

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

.nav__links a:hover::after {
  width: 100%;
}

.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.25rem;
}

.nav__hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav__hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__hamburger.open span:nth-child(2) { opacity: 0; }
.nav__hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: var(--nav-height);
  position: relative;
  background:
    radial-gradient(ellipse 80% 60% at 50% -10%, #dbeafe 0%, transparent 70%),
    var(--color-bg);
}

.hero__inner {
  padding-block: 5rem 3rem;
}

.hero__eyebrow {
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  color: var(--color-accent);
  font-weight: 500;
  margin-bottom: 0.75rem;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.1s forwards;
}

.hero__name {
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.05;
  color: var(--color-text);
  margin-bottom: 0.5rem;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.2s forwards;
}

.hero__title {
  font-size: clamp(1.125rem, 3vw, 1.5rem);
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.3s forwards;
}

.hero__tagline {
  font-size: clamp(1rem, 2vw, 1.125rem);
  color: var(--color-text-muted);
  max-width: 52ch;
  line-height: 1.7;
  margin-bottom: 2.5rem;
  text-align: justify;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.4s forwards;
}

.hero__cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.5s forwards;
}

.hero__scroll-hint {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  justify-content: center;
}

.hero__scroll-hint span {
  display: block;
  width: 24px;
  height: 38px;
  border: 2px solid var(--color-border);
  border-radius: 12px;
  position: relative;
}

.hero__scroll-hint span::after {
  content: '';
  position: absolute;
  top: 6px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  background: var(--color-accent);
  border-radius: 2px;
  animation: scrollBounce 1.5s ease infinite;
}

/* ===== ABOUT ===== */
.about__text {
  max-width: 680px;
}

.about__text p {
  color: var(--color-text-muted);
  margin-top: 1rem;
  font-size: 1.0625rem;
  line-height: 1.75;
  text-align: justify;
}

/* ===== SKILLS ===== */
.skills__categories {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.skill-group {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow-sm);
}

.skill-group__label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.875rem;
}

.skill-group__label svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
  stroke: var(--color-accent);
}

.skill-group__badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.skill-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.3rem 0.75rem;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 9999px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text);
  cursor: default;
  transition: border-color 0.2s ease, background 0.2s ease, color 0.2s ease,
              transform 0.2s ease, box-shadow 0.2s ease;
}

.skill-badge img {
  width: 13px;
  height: 13px;
  object-fit: contain;
  flex-shrink: 0;
}

.skill-badge svg {
  width: 13px;
  height: 13px;
  flex-shrink: 0;
  stroke: var(--color-accent);
  fill: none;
}

.skill-badge:hover {
  border-color: var(--color-accent);
  background: var(--color-accent-light);
  color: var(--color-accent);
  transform: translateY(-2px) scale(1.04);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
}

/* ===== PROJECTS ===== */
.projects__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}

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

.project-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.project-card__number {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
}

.project-card__icon {
  width: 40px;
  height: 40px;
  background: var(--color-accent-light);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
}

.project-card__icon svg {
  width: 20px;
  height: 20px;
}

.project-card__title {
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-text);
}

.project-card__desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  line-height: 1.65;
  flex: 1;
}

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

.project-card__tags li {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.25rem 0.625rem;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: var(--radius-sm);
}

.project-card__link {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-accent);
  transition: gap var(--transition);
}

.project-card__link:hover {
  gap: 0.625rem;
}

.project-card__link svg {
  width: 14px;
  height: 14px;
}

/* ===== CONTACT ===== */
.contact__inner {
  max-width: 600px;
  margin-inline: auto;
  text-align: center;
}

.contact__desc {
  color: var(--color-text-muted);
  font-size: 1.0625rem;
  margin-top: 1rem;
  margin-bottom: 2rem;
  line-height: 1.7;
}

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

.contact__social {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

.contact__social:hover {
  color: var(--color-accent);
}

.contact__social svg {
  width: 20px;
  height: 20px;
}

/* ===== FOOTER ===== */
.footer {
  border-top: 1px solid var(--color-border);
  padding-block: 1.5rem;
}

.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* ===== SCROLL REVEAL ANIMATION ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ===== KEYFRAMES ===== */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

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

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
  .projects__grid {
    grid-template-columns: 1fr;
    max-width: 560px;
    margin-inline: auto;
  }


}

@media (max-width: 900px) {
  .skills__categories {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .section { padding-block: 4rem; }

  .nav__links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.97);
    backdrop-filter: blur(12px);
    flex-direction: column;
    gap: 0;
    padding: 0.5rem 0 1rem;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-110%);
    transition: transform 0.3s ease;
    z-index: 99;
  }

  .nav__links.open {
    transform: translateY(0);
  }

  .nav__links a {
    padding: 0.875rem 1.5rem;
    width: 100%;
    font-size: 1rem;
  }

  .nav__links a::after { display: none; }

  .nav__hamburger {
    display: flex;
  }

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

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

  .footer__inner {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }

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