:root {
  --bg-dark: #0a0a0a;
  --bg-darker: #050505;
  --bg-light: #1a1a1a;
  --text-primary: #f0f0f0;
  --text-secondary: #b0b0b0;
  --border-color: #2a2a2a;
  --accent: #ffffff;
  --accent-hover: #cccccc;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
  --transition: all 0.3s ease;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.6;
}

header {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0.8rem 2rem;
  background-color: var(--bg-darker);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.hamburger {
  font-size: 2rem;
  cursor: pointer;
  color: var(--text-primary);
  transition: var(--transition);
  line-height: 1;
  user-select: none;
}

.hamburger:hover {
  color: var(--accent-hover);
  transform: scale(1.1);
}

.logo a {
  display: flex;
  align-items: center;
}

.logo img {
  max-height: 60px;
  width: auto;
  transition: var(--transition);
}

.logo img:hover {
  opacity: 0.8;
}

.header-center {
  justify-self: center;
}

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

.header-center nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.5px;
  padding: 0.5rem 0;
  border-bottom: 2px solid transparent;
  transition: var(--transition);
}

.header-center nav a:hover {
  color: var(--text-primary);
  border-bottom-color: var(--text-primary);
}

.header-right {
  display: flex;
  gap: 1.2rem;
  align-items: center;
  justify-self: end;
}

.header-right a {
  color: var(--text-secondary);
  font-size: 1.4rem;
  transition: var(--transition);
  text-decoration: none;
}

.header-right a:hover {
  color: var(--text-primary);
  transform: translateY(-2px);
}

.sidebar {
  position: fixed;
  top: 0;
  left: -300px;
  width: 280px;
  height: 100vh;
  background-color: var(--bg-light);
  border-right: 1px solid var(--border-color);
  box-shadow: var(--shadow);
  transition: left 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 200;
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
}

.sidebar.show {
  left: 0;
}

.sidebar a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 1.2rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
  font-weight: 500;
}

.sidebar a:hover {
  color: var(--text-primary);
  padding-left: 0.5rem;
}

.sidebar-icons {
  margin-top: 2rem;
  display: flex;
  gap: 1.5rem;
  justify-content: center;
}

.sidebar-icons a {
  font-size: 1.8rem;
  border-bottom: none;
  padding: 0;
  color: var(--text-secondary);
  text-decoration: none;
}

.sidebar-icons a:hover {
  color: var(--text-primary);
  transform: scale(1.1);
  padding-left: 0;
}

.sidebar-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.8rem;
  cursor: pointer;
  line-height: 1;
  padding: 0.5rem;
  transition: var(--transition);
}

.sidebar-close:hover {
  color: var(--text-primary);
  transform: scale(1.1);
}

.overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 150;
  backdrop-filter: blur(3px);
}

.overlay.show {
  display: block;
}

@media (max-width: 768px) {
  header {
    padding: 0.8rem 1rem;
    grid-template-columns: auto 1fr auto;
  }

  .header-center nav {
    display: none;
  }

  .header-right {
    gap: 1rem;
  }

  .header-right a {
    font-size: 1.2rem;
  }

  .logo img {
    max-height: 45px;
  }

  .sidebar {
    width: 240px;
  }
}

@media (min-width: 769px) {
  .hamburger {
    display: none;
  }
}