/* --------------------
   Global Reset & Base
-------------------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
  color: #222;
  background-color: #fafafa;
}

/* Utility */
.container {
  width: 90%;
  max-width: 1000px;
  margin: 0 auto;
  padding: 2rem 0;
}

a {
  color: #0066cc;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* --------------------
   Header & Navigation
-------------------- */
header {
  background: #fff;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 1000;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 5%;
}

.logo {
  font-weight: bold;
  font-size: 1.25rem;
  color: #222;
}

.nav-list {
  list-style: none;
  display: flex;
  gap: 1rem;
}

.nav-list a {
  padding: 0.5rem 0.75rem;
  border-radius: 5px;
  transition: background 0.2s ease;
}

.nav-list a:hover {
  background: rgba(0, 102, 204, 0.1);
}

/* --------------------
   Hero Section
-------------------- */
#hero {
  text-align: center;
  padding: 6rem 5%;
  background: linear-gradient(135deg, #0066cc, #00b4d8);
  color: #fff;
}

#hero h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

#hero .highlight {
  color: #D9ECE5;
}

#hero p {
  font-size: 1.25rem;
  margin-bottom: 2rem;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: #D9ECE5;
  color: #222;
  font-weight: bold;
  border-radius: 8px;
  transition: background 0.2s ease;
}

.btn:hover {
  background: #FFE8D1;
}

/* --------------------
   Sections
-------------------- */
section {
  padding: 4rem 5%;
}

section h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

/* About */
#about {
  background: #fff;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

/* Projects */
.project-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.project-card {
  background: #fff;
  border-radius: 10px;
  padding: 1.5rem;
  box-shadow: 0 2px 6px rgba(0,0,0,0.05);
  transition: transform 0.2s ease;
}

.project-card:hover {
  transform: translateY(-5px);
}

.project-card img {
  max-width: 100%;
  border-radius: 8px;
  margin-bottom: 1rem;
}

.project-card h3 {
  margin-bottom: 0.5rem;
}

/* Contact */
#contact ul {
  list-style: none;
  text-align: center;
}

#contact li {
  margin: 0.5rem 0;
}

/* --------------------
   Footer
-------------------- */
footer {
  text-align: center;
  padding: 2rem;
  background: #f1f1f1;
  font-size: 0.9rem;
  color: #555;
}

/* --------------------
   Accessibility
-------------------- */
.skip-link {
  position: absolute;
  left: -999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.skip-link:focus {
  position: static;
  width: auto;
  height: auto;
  padding: 1rem;
  background: #ffd166;
  color: #222;
  z-index: 10000;
}

/* --------------------
   Responsive
-------------------- */
@media (max-width: 768px) {
  nav {
    flex-direction: column;
  }
  .nav-list {
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 0.5rem;
  }
  #hero h1 {
    font-size: 2rem;
  }
}

/* --------------------
   Mobile Nav Toggle
-------------------- */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
}

@media (max-width: 768px) {
  .nav-toggle {
    display: block;
    margin-bottom: 0.5rem;
  }
  .nav-list {
    display: none;
    flex-direction: column;
    gap: 0.75rem;
    background: #fff;
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.05);
  }
  .nav-list.nav-open {
    display: flex;
  }
}

/* --------------------
   Fade-in Animations
-------------------- */
section, .project-card {
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.6s ease;
}

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