/* =========================
   RESET / BASE
========================= */

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


/* =========================
   ROOT VARIABLES
========================= */

:root {
  --max-width: 1120px;

  --color-bg: #ffffff;
  --color-bg-alt: #fafbfc;
  --color-surface: #ffffff;
  --color-text: #1f2937;
  --color-text-muted: #5f6b7a;
  --color-border: #e5e7eb;
  --color-accent: #355c7d;
  --color-accent-dark: #27445c;

  --shadow-sm: 0 8px 20px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 18px 40px rgba(15, 23, 42, 0.08);

  --radius: 14px;

  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-section: 5.5rem;
}


/* =========================
   GLOBAL STYLES
========================= */

html {
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  line-height: 1.65;
  background: var(--color-bg);
  color: var(--color-text);
}


/* =========================
   TYPOGRAPHY
========================= */

h1,
h2,
h3 {
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 3.25rem;
}

h2 {
  font-size: 2.15rem;
}

h3 {
  font-size: 1.25rem;
}

p {
  margin-top: 0.5rem;
  color: var(--color-text);
}

.section-title {
  margin-bottom: var(--spacing-lg);
}


/* =========================
   LAYOUT
========================= */

.container {
  width: min(100%, var(--max-width));
  margin: 0 auto;
  padding: 0 1.5rem;
}

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

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


/* =========================
   LINKS / BUTTONS
========================= */

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.btn {
  display: inline-block;
  padding: 0.9rem 1.35rem;
  border-radius: var(--radius);
  background: var(--color-accent);
  color: #ffffff;
  font-weight: 600;
  transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.btn:hover {
  background: var(--color-accent-dark);
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: transparent;
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
  box-shadow: none;
}

.btn-secondary:hover {
  background: var(--color-accent);
  color: #ffffff;
}


/* =========================
   IMAGES
========================= */

img {
  max-width: 100%;
  display: block;
  border-radius: var(--radius);
}


/* =========================
   HEADER / NAV
========================= */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(10px);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 76px;
  gap: 1rem;
}

.logo a {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.site-nav .nav-list {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 2rem;
}

.site-nav a {
  font-weight: 600;
  color: var(--color-text);
}

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

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--color-border);
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  font-size: 1.25rem;
  cursor: pointer;
}


/* =========================
   HOME / HERO
========================= */

.home-section {
  padding-top: 7rem;
  padding-bottom: 6.5rem;
}

.hero {
  max-width: 860px;
}

.hero-title {
  margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--color-accent);
  font-weight: 700;
  margin-bottom: var(--spacing-md);
}

.hero-intro {
  max-width: 72ch;
  color: var(--color-text-muted);
  font-size: 1.08rem;
  margin-bottom: var(--spacing-xl);
}

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


/* =========================
   ABOUT
========================= */

.about-intro {
  max-width: 72ch;
  color: var(--color-text-muted);
  margin-bottom: var(--spacing-xl);
  font-size: 1.05rem;
}

.skills {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem;
}

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

.skills-group h3 {
  margin-bottom: 0.85rem;
}

.skills-group ul {
  list-style: none;
}

.skills-group li + li {
  margin-top: 0.55rem;
}


/* =========================
   PROJECTS
========================= */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.75rem;
}

.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: #d7dce3;
}

.project-title {
  margin-bottom: 0.85rem;
}

.project-description {
  color: var(--color-text-muted);
  margin-bottom: 1rem;
}

.project-tech {
  margin-bottom: 1rem;
}

.project-link {
  color: var(--color-accent);
  font-weight: 700;
}

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


/* =========================
   CONTACT
========================= */

.contact-intro {
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
}

.contact-icons {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.contact-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 58px;
  height: 58px;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
  font-size: 1.5rem;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease,
    border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-icon:hover {
  transform: translateY(-3px);
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #ffffff;
  box-shadow: var(--shadow-md);
}


/* =========================
   FOOTER
========================= */

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2.25rem 0;
  margin-top: 0;
}

.site-footer .container {
  text-align: center;
}

.footer-text {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.back-to-top {
  display: inline-block;
  margin-top: 0.75rem;
  color: var(--color-accent);
  font-weight: 700;
}


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

@media (max-width: 768px) {
  h1 {
    font-size: 2.45rem;
  }

  h2 {
    font-size: 1.8rem;
  }

  .site-header .container {
    flex-wrap: wrap;
    min-height: auto;
    padding-top: 1rem;
    padding-bottom: 1rem;
  }

  .nav-toggle {
    display: inline-block;
  }

  .site-nav {
    display: none;
    width: 100%;
  }

  .site-nav.nav-open {
    display: block;
  }

  .site-nav .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
    padding-top: 1rem;
  }

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

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

  .home-section {
    padding-top: 4.5rem;
    padding-bottom: 4.5rem;
  }

  .container {
    padding: 0 1rem;
  }

  
}