/* ============================================
   CSS Variables & Reset
   ============================================ */
:root {
  --color-bg: #0a0f1c;
  --color-bg-alt: #111827;
  --color-surface: #1a2236;
  --color-accent: #3b82f6;
  --color-accent-hover: #2563eb;
  --color-accent-glow: rgba(59, 130, 246, 0.15);
  --color-text: #e2e8f0;
  --color-text-muted: #94a3b8;
  --color-border: #1e293b;
  --color-white: #ffffff;
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 30px var(--color-accent-glow);
  --transition: 0.3s ease;
  --max-width: 1100px;
}

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font-family);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

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

ul {
  list-style: none;
}

/* ============================================
   Reusable Layout Classes
   ============================================ */
.container {
  width: 90%;
  max-width: var(--max-width);
  margin: 0 auto;
}

.section {
  padding: 100px 0;
}

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

.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 3rem;
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: var(--color-accent);
  border-radius: 2px;
  margin: 0.75rem auto 0;
}

/* ============================================
   Reusable Flex / Grid Utilities
   ============================================ */
.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.text-accent {
  color: var(--color-accent);
}

/* ============================================
   Reusable Button Elements
   ============================================ */
.btn {
  display: inline-block;
  padding: 12px 32px;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: var(--font-family);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  border: 2px solid transparent;
  text-align: center;
}

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

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

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

.btn-outline:hover {
  background: var(--color-accent);
  color: var(--color-white);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 8px 20px;
  font-size: 0.85rem;
}

.btn-block {
  display: block;
  width: 100%;
}

/* ============================================
   Reusable Tag Element
   ============================================ */
.tag {
  display: inline-block;
  padding: 4px 12px;
  font-size: 0.75rem;
  font-weight: 500;
  background: var(--color-accent-glow);
  color: var(--color-accent);
  border-radius: 999px;
  letter-spacing: 0.02em;
}

/* ============================================
   Reusable Form Elements
   ============================================ */
.form-group {
  margin-bottom: 1.25rem;
}

.form-input {
  width: 100%;
  padding: 14px 18px;
  font-size: 0.95rem;
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  outline: none;
  transition: var(--transition);
}

.form-input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-glow);
}

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

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

/* ============================================
   Reusable Card Element
   ============================================ */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem;
  transition: var(--transition);
}

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

/* ============================================
   Navbar
   ============================================ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 1rem 0;
  z-index: 1000;
  background: rgba(10, 15, 28, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}

.navbar.scrolled {
  border-bottom-color: var(--color-border);
}

.nav-logo {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: var(--transition);
  position: relative;
}

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

.nav-link:hover,
.nav-link.active {
  color: var(--color-white);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.hamburger,
.hamburger::before,
.hamburger::after {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: var(--transition);
}

.hamburger {
  position: relative;
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
}

.hamburger::before {
  top: -7px;
}

.hamburger::after {
  top: 7px;
}

.nav-toggle.open .hamburger {
  background: transparent;
}

.nav-toggle.open .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle.open .hamburger::after {
  top: 0;
  transform: rotate(-45deg);
}

/* ============================================
   Hero
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 80px;
}

.hero-greeting {
  font-size: 1.1rem;
  color: var(--color-accent);
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 0.75rem;
}

.hero-subtitle {
  font-size: clamp(1.2rem, 3vw, 1.6rem);
  color: var(--color-text-muted);
  font-weight: 400;
  margin-bottom: 1.5rem;
}

.hero-description {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  max-width: 540px;
  margin-bottom: 2.5rem;
  line-height: 1.8;
}

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

/* ============================================
   About
   ============================================ */
.about-content {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-text p {
  margin-bottom: 1.25rem;
  color: var(--color-text-muted);
  font-size: 1rem;
}

.about-stats {
  display: grid;
  gap: 1rem;
}

.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  text-align: center;
  transition: var(--transition);
}

.stat-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-glow);
}

.stat-number {
  display: block;
  font-size: 1.5rem;
  font-weight: 700;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* ============================================
   Skills
   ============================================ */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
}

.skill-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem 1.5rem;
  text-align: center;
  transition: var(--transition);
}

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

.skill-icon {
  font-size: 2rem;
  margin-bottom: 1rem;
}

.skill-name {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.skill-desc {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* ============================================
   Projects
   ============================================ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
}

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

.project-image {
  width: 100%;
  height: 200px;
  background: linear-gradient(135deg, var(--color-bg), var(--color-bg-alt));
  display: flex;
  align-items: center;
  justify-content: center;
}

.project-placeholder {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
}

.project-info {
  padding: 1.5rem;
}

.project-title {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.project-desc {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 1rem;
  line-height: 1.6;
}

.project-tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

.project-links {
  display: flex;
  gap: 0.75rem;
}

/* ============================================
   Contact
   ============================================ */
.contact-intro {
  text-align: center;
  color: var(--color-text-muted);
  margin-bottom: 2.5rem;
  font-size: 1.05rem;
}

.contact-form {
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  padding: 2.5rem 0;
  border-top: 1px solid var(--color-border);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 1rem;
}

.footer-link {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  transition: var(--transition);
}

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

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

/* ============================================
   Animations
   ============================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInUp 0.6s ease forwards;
}

.delay-1 { animation-delay: 0.15s; }
.delay-2 { animation-delay: 0.3s; }
.delay-3 { animation-delay: 0.45s; }
.delay-4 { animation-delay: 0.6s; }

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

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 70%;
    max-width: 300px;
    height: 100vh;
    background: var(--color-surface);
    flex-direction: column;
    padding: 5rem 2rem 2rem;
    gap: 1.5rem;
    transition: right 0.35s ease;
    box-shadow: -4px 0 30px rgba(0, 0, 0, 0.5);
  }

  .nav-links.open {
    right: 0;
  }

  .nav-toggle {
    display: block;
    z-index: 1001;
  }

  .hero-title {
    font-size: 2.2rem;
  }

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

  .about-stats {
    grid-template-columns: repeat(3, 1fr);
  }

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

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

  .section {
    padding: 70px 0;
  }
}

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

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

  .hero-actions {
    flex-direction: column;
  }

  .btn {
    text-align: center;
  }
}