:root {
  --bg-color: #0e0e0e;
  --text-color: #eaeaea;
  --accent-color: #0a3ada;
  --card-bg: #1f1f1f;
  --nav-bg: #111;
  --footer-color: #aaa;
}

body.light {
  --bg-color: #ffffff;
  --text-color: #111111;
  --accent-color: #1b0edc;
  --card-bg: #f0f0f0;
  --nav-bg: #f9f9f9;
  --footer-color: #333;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  background-color: var(--bg-color);
  color: var(--text-color);
}

header {
  background-color: var(--nav-bg);
  text-align: center;
  padding: 30px 20px 20px;
}

header img {
  border-radius: 50%;
  width: 130px;
  height: 130px;
  object-fit: cover;
  border: 3px solid var(--accent-color);
  margin-top: 10px;
}

/* Navbar */
nav {
  position: sticky;
  top: 0;
  background-color: var(--nav-bg);
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  padding: 10px;
  z-index: 1000;
  box-shadow: 0 2px 4px rgba(0,0,0,0.6);
  align-items: center;
}

nav a {
  margin: 8px 15px;
  color: var(--accent-color);
  text-decoration: none;
  font-weight: bold;
  font-size: 16px;
}

nav a:hover {
  text-decoration: underline;
}

/* Toggle menu (mobile) */
.menu-toggle {
  display: none;
  font-size: 26px;
  background: none;
  color: var(--accent-color);
  border: none;
  position: absolute;
  top: 12px;
  right: 20px;
  cursor: pointer;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  width: 100%;
  gap: 10px;
}

@media (max-width: 600px) {
  .nav-links {
    display: none;
    flex-direction: column;
    background-color: var(--nav-bg);
    width: 100%;
    text-align: center;
    padding: 10px 0;
  }

  .nav-links.show {
    display: flex;
  }

  .menu-toggle {
    display: block;
  }

  nav {
    justify-content: flex-start;
    padding: 10px 20px;
  }

  #themeToggle {
    margin: 10px auto 0;
  }
}

/* Tombol Tema */
#themeToggle {
  color: var(--accent-color);
  background: none;
  border: none;
  font-size: 20px;
  cursor: pointer;
  padding: 4px 8px;
  transition: color 0.3s ease;
  margin-left: auto;
}

#themeToggle:hover {
  color: #0822df;
}

/* Section */
section {
  padding: 40px 20px;
  max-width: 960px;
  margin: auto;
}

h2 {
  border-bottom: 2px solid var(--accent-color);
  padding-bottom: 8px;
  color: var(--accent-color);
}

.projects {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.project-card {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.6);
  transition: transform 0.3s ease;
}

.project-card:hover {
  transform: scale(1.03);
}

/* Footer */
footer {
  background-color: var(--nav-bg);
  color: var(--footer-color);
  text-align: center;
  padding: 25px 20px;
  margin-top: 60px;
}

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

a:hover {
  text-decoration: underline;
}

/* Tombol Scroll Atas */
#backToTop {
  display: none;
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 999;
  font-size: 24px;
  background-color: var(--accent-color);
  color: white;
  border: none;
  border-radius: 50%;
  padding: 12px 16px;
  cursor: pointer;
  box-shadow: 0 4px 10px rgba(0,0,0,0.4);
  transition: background-color 0.3s ease;
}

#backToTop:hover {
  background-color: #2706cd;
}