/* ========================================
   Design System — Navy Professional
   ======================================== */

:root {
  --color-primary: #0F172A;
  --color-secondary: #334155;
  --color-accent: #0369A1;
  --color-accent-light: #0EA5E9;
  --color-bg: #F8FAFC;
  --color-bg-alt: #F1F5F9;
  --color-text: #020617;
  --color-text-muted: #64748B;
  --color-border: #E2E8F0;

  --font: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --radius: 8px;
  --radius-lg: 12px;
  --transition: 200ms ease;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 8px 24px rgba(15, 23, 42, 0.12);
}

/* ========================================
   Reset & Base
   ======================================== */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

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

/* ========================================
   Layout
   ======================================== */

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 48px 0;
}

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

.section__title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 32px;
  position: relative;
}

.section__title::after {
  content: '';
  display: block;
  width: 48px;
  height: 3px;
  background: var(--color-accent);
  margin-top: 12px;
  border-radius: 2px;
}

/* ========================================
   Button
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  background: var(--color-accent);
  color: #fff;
  font-family: var(--font);
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
}

.btn:hover {
  background: var(--color-accent-light);
  color: #fff;
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

/* ========================================
   Navbar
   ======================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(248, 250, 252, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: background var(--transition), border-color var(--transition);
}

.navbar--scrolled {
  background: rgba(248, 250, 252, 0.95);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.navbar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.navbar__logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: -0.02em;
}

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

.navbar__links {
  display: flex;
  list-style: none;
  gap: 32px;
}

.navbar__links a {
  color: var(--color-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
}

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

.navbar__lang {
  display: flex;
  align-items: center;
  padding: 6px 12px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-family: var(--font);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

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

/* Hamburger toggle */
.navbar__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.navbar__toggle-icon,
.navbar__toggle-icon::before,
.navbar__toggle-icon::after {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-primary);
  border-radius: 1px;
  transition: all var(--transition);
}

.navbar__toggle-icon {
  position: relative;
}

.navbar__toggle-icon::before,
.navbar__toggle-icon::after {
  content: '';
  position: absolute;
  left: 0;
}

.navbar__toggle-icon::before {
  top: -7px;
}

.navbar__toggle-icon::after {
  top: 7px;
}

/* Hamburger open state */
.navbar__toggle[aria-expanded="true"] .navbar__toggle-icon {
  background: transparent;
}

.navbar__toggle[aria-expanded="true"] .navbar__toggle-icon::before {
  top: 0;
  transform: rotate(45deg);
}

.navbar__toggle[aria-expanded="true"] .navbar__toggle-icon::after {
  top: 0;
  transform: rotate(-45deg);
}

/* ========================================
   Hero
   ======================================== */

.hero {
  padding-top: 120px;
  padding-bottom: 64px;
  min-height: 80vh;
  display: flex;
  align-items: center;
}

.hero__inner {
  max-width: 680px;
}

.hero__greeting {
  font-size: 1.1rem;
  color: var(--color-accent);
  font-weight: 500;
  margin-bottom: 8px;
}

.hero__name {
  font-size: 3rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.hero__tagline {
  font-size: 1.15rem;
  color: var(--color-secondary);
  font-weight: 500;
  margin-bottom: 16px;
}

.hero__description {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  margin-bottom: 32px;
  max-width: 560px;
}

/* ========================================
   About
   ======================================== */

.about__content {
  max-width: 720px;
}

.about__content p {
  color: var(--color-secondary);
  margin-bottom: 16px;
  line-height: 1.75;
}

.about__content p:last-child {
  margin-bottom: 0;
}

/* ========================================
   Experience Timeline
   ======================================== */

.timeline {
  position: relative;
  padding-left: 28px;
  max-width: 720px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--color-border);
}

.timeline__item {
  position: relative;
  padding-bottom: 32px;
}

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

.timeline__marker {
  position: absolute;
  left: -28px;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 2px solid var(--color-bg-alt);
}

.timeline__role {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.timeline__org {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-accent);
  margin-bottom: 4px;
}

.timeline__period {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 12px;
}

.timeline__list {
  list-style: none;
  padding: 0;
}

.timeline__list li {
  position: relative;
  padding-left: 16px;
  font-size: 0.92rem;
  color: var(--color-secondary);
  line-height: 1.6;
  margin-bottom: 6px;
}

.timeline__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--color-text-muted);
}

.timeline__list li:last-child {
  margin-bottom: 0;
}

/* ========================================
   Projects
   ======================================== */

.projects__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.card {
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: transform var(--transition), box-shadow var(--transition);
  position: relative;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.card__badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-accent);
  background: rgba(3, 105, 161, 0.08);
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.card__badge--live {
  color: #15803d;
  background: rgba(21, 128, 61, 0.08);
}

.card__title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.card__description {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}

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

.tag {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--color-secondary);
  background: var(--color-bg-alt);
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--color-border);
}

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

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

.card__link svg {
  flex-shrink: 0;
}

/* ========================================
   Skills
   ======================================== */

.skills__categories {
  display: flex;
  flex-direction: column;
  gap: 36px;
}

.skills__category-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

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

.skill {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.skill:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}

.skill__icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--color-accent);
}

.skill__name {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-primary);
}

/* ========================================
   Contact
   ======================================== */

.contact__cta {
  font-size: 1.15rem;
  color: var(--color-secondary);
  margin-bottom: 32px;
  max-width: 520px;
}

.contact__links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.contact__link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  color: var(--color-primary);
  font-weight: 500;
  font-size: 0.95rem;
  transition: all var(--transition);
}

.contact__link:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}

.contact__link svg {
  color: var(--color-accent);
  flex-shrink: 0;
}

/* ========================================
   Footer
   ======================================== */

.footer {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer p {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.footer__heart {
  color: #ef4444;
}

/* ========================================
   Scroll Animations
   ======================================== */

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

/* ========================================
   Responsive — Tablet (768px)
   ======================================== */

@media (min-width: 768px) {
  .section {
    padding: 80px 0;
  }

  .hero {
    padding-top: 160px;
    padding-bottom: 80px;
  }

  .hero__name {
    font-size: 3.75rem;
  }

  .section__title {
    font-size: 2rem;
  }

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

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

/* ========================================
   Responsive — Desktop (1024px)
   ======================================== */

@media (min-width: 1024px) {
  .hero__name {
    font-size: 4.25rem;
  }

  .skills__grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ========================================
   Responsive — Mobile (< 768px)
   ======================================== */

@media (max-width: 767px) {
  .navbar__toggle {
    display: flex;
  }

  .navbar__links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(248, 250, 252, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s ease;
  }

  .navbar__links--open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .navbar__links li {
    width: 100%;
    text-align: center;
  }

  .navbar__links a {
    display: block;
    padding: 12px 24px;
    font-size: 1rem;
  }

  .navbar__lang {
    order: -1;
    margin-right: auto;
    margin-left: 0;
  }

  .hero {
    min-height: auto;
    padding-top: 100px;
    padding-bottom: 48px;
  }

  .hero__name {
    font-size: 2.25rem;
  }

  .hero__tagline {
    font-size: 1rem;
  }
}