/* Sticky Navigation Enhancements for ENTM201L */
/* Preserves Dracula theme colors and mobile functionality */

:root {
  --nav-height: 70px;
  --nav-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Base sticky navigation */
.navbar.sticky-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  transition: var(--nav-transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

/* Scrolled state - slightly condensed with enhanced shadow */
.navbar.sticky-nav.scrolled {
  padding: 0.75rem 0;
  box-shadow: 0 4px 20px rgba(189, 147, 249, 0.3);
  background: rgba(36, 40, 59, 0.95);
}

.navbar.sticky-nav.scrolled .nav-brand a {
  font-size: 1.6em;
  transition: font-size 0.3s ease;
}

.navbar.sticky-nav.scrolled .since-date {
  font-size: 0.85em;
}

/* Active page indicator with gradient underline */
.nav-menu li a.active {
  color: var(--purple);
  position: relative;
}

.nav-menu li a.active::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--purple) 0%, var(--cyan) 100%);
  border-radius: 2px;
  animation: slideIn 0.3s ease forwards;
}

@keyframes slideIn {
  from {
    transform: scaleX(0);
  }
  to {
    transform: scaleX(1);
  }
}

/* Smooth hover effects for nav links */
.nav-menu li a {
  position: relative;
  transition: var(--nav-transition);
  padding-bottom: 8px;
}

.nav-menu li a::before {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--purple) 0%, var(--cyan) 100%);
  border-radius: 2px;
  transition: transform 0.3s ease;
  transform-origin: center;
}

.nav-menu li a:hover::before {
  transform: translateX(-50%) scaleX(1);
}

.nav-menu li a.active:hover::before {
  display: none; /* Don't show hover effect on active page */
}

/* Ensure content doesn't hide under sticky nav */
.hero-section {
  padding-top: 8rem;
  margin-top: calc(var(--nav-height) * -1);
}

.section:first-of-type {
  padding-top: 2rem;
}

/* Mobile sticky nav adjustments */
@media (max-width: 768px) {
  .navbar.sticky-nav {
    padding: 1rem 0;
  }

  .navbar.sticky-nav.scrolled {
    padding: 0.75rem 0;
  }

  .navbar.sticky-nav.scrolled .nav-brand a {
    font-size: 1.4em;
  }

  .hero-section {
    padding-top: 6rem;
    margin-top: -60px;
  }

  /* Enhanced mobile menu for sticky nav */
  .nav-menu.active {
    position: fixed;
    top: var(--nav-height);
    right: 0;
    background: linear-gradient(135deg, #282a36 0%, #44475a 100%);
    height: calc(100vh - var(--nav-height));
    overflow-y: auto;
    box-shadow: -10px 0 30px rgba(0, 0, 0, 0.7);
  }

  /* Prevent body scroll when mobile menu is open */
  body.menu-open {
    overflow: hidden;
    position: fixed;
    width: 100%;
  }
}

/* Preserve hamburger menu Dracula theme colors */
.nav-toggle span {
  background: var(--purple);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  height: 3px;
  border-radius: 2px;
}

.nav-toggle.active span:nth-child(1) {
  background: var(--cyan);
  transform: rotate(45deg) translateY(8px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
  transform: translateX(10px);
}

.nav-toggle.active span:nth-child(3) {
  background: var(--cyan);
  transform: rotate(-45deg) translateY(-8px);
}

/* Back to top button enhancement for sticky nav */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: linear-gradient(135deg, var(--purple) 0%, var(--cyan) 100%);
  color: var(--bg-dark);
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: none;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: all 0.3s ease;
  z-index: 999;
  box-shadow: 0 4px 15px rgba(189, 147, 249, 0.4);
}

.back-to-top:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 20px rgba(189, 147, 249, 0.6);
}

.back-to-top i {
  font-size: 1.2rem;
}

/* Smooth scroll behavior */
html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

/* Navigation visibility on scroll (optional enhancement) */
.navbar.sticky-nav.hide-nav {
  transform: translateY(-100%);
}

.navbar.sticky-nav.show-nav {
  transform: translateY(0);
}

/* Loading state for page transitions */
.page-loading {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--purple) 0%, var(--cyan) 50%, var(--purple) 100%);
  background-size: 200% 100%;
  animation: loading 1.5s linear infinite;
  z-index: 1001;
}

@keyframes loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

/* Focus states for accessibility */
.navbar a:focus,
.navbar button:focus {
  outline: 2px solid var(--purple);
  outline-offset: 2px;
  border-radius: 4px;
}

/* Skip to main content link (accessibility) */
.skip-to-main {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--purple);
  color: var(--bg-dark);
  padding: 8px;
  text-decoration: none;
  z-index: 1001;
  border-radius: 0 0 8px 0;
  transition: top 0.3s ease;
}

.skip-to-main:focus {
  top: 0;
}

/* Print styles - hide nav when printing */
@media print {
  .navbar.sticky-nav {
    display: none;
  }

  .hero-section,
  .section:first-of-type {
    margin-top: 0;
    padding-top: 1rem;
  }
}