/* Layout and Structure */

/* Global Layout */
body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

/* Header / AppBar */
.header {
  background-color: rgba(0, 30, 43, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--pure-white);
  padding: var(--space-md) 0;
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  box-shadow: var(--shadow-md);
  border-bottom: 1px solid rgba(0, 237, 100, 0.1);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
}

/* Navigation Menu */
.header-menu {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex: 1;
  justify-content: center;
}

.nav-link {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--teal-gray);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  position: relative;
}

.nav-link:hover {
  color: var(--mongodb-green);
  background-color: rgba(0, 237, 100, 0.1);
}

.nav-link.active {
  color: var(--mongodb-green);
  background-color: rgba(0, 237, 100, 0.15);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--mongodb-green);
  transition: all var(--transition-base);
  transform: translateX(-50%);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 80%;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--pure-white);
  font-size: 28px;
  cursor: pointer;
  padding: var(--space-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.mobile-menu-toggle:hover {
  background-color: rgba(0, 237, 100, 0.1);
  color: var(--mongodb-green);
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  text-decoration: none;
  color: var(--pure-white);
}

.header-logo-icon {
  font-size: 32px;
  color: var(--mongodb-green);
}

.header-logo-text {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: var(--weight-normal);
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Theme Selector */
.theme-selector {
  display: flex;
  gap: var(--space-xs);
  align-items: center;
}

.theme-btn {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-base);
  position: relative;
}

.theme-btn:hover {
  border-color: var(--pure-white);
}

.theme-btn.active {
  border-color: var(--mongodb-green);
  box-shadow: 0 0 0 2px var(--forest-black), 0 0 0 4px var(--mongodb-green);
}

.theme-btn-forest {
  background: linear-gradient(135deg, var(--forest-black) 50%, var(--mongodb-green) 50%);
}

.theme-btn-ocean {
  background: linear-gradient(135deg, #001e2b 50%, #00bcd4 50%);
}

.theme-btn-sunset {
  background: linear-gradient(135deg, #2b1e00 50%, #ff7043 50%);
}

.theme-btn-galaxy {
  background: linear-gradient(135deg, #1e002b 50%, #7c4dff 50%);
}

.theme-btn-classic {
  background: linear-gradient(135deg, #1a1a1a 50%, #4caf50 50%);
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--forest-black) 0%, #002a3a 100%);
  color: var(--pure-white);
  padding: var(--space-3xl) 0 var(--space-2xl);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 50% 50%, rgba(0, 237, 100, 0.15) 0%, transparent 50%);
  pointer-events: none;
  opacity: 0.6;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 100px;
  background: linear-gradient(to bottom, transparent, var(--pure-white));
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  margin-bottom: var(--space-lg);
  color: var(--pure-white);
  text-shadow: 0 4px 20px rgba(0, 237, 100, 0.3);
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--teal-gray);
  margin-bottom: var(--space-xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.6;
}

.hero-label {
  font-family: var(--font-code);
  font-size: var(--text-sm);
  color: var(--mongodb-green);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: var(--space-md);
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background: rgba(0, 237, 100, 0.1);
  border-radius: var(--radius-pill);
  border: 1px solid rgba(0, 237, 100, 0.3);
}

/* Hero Title — animated variant */
@keyframes heroTitleFloat {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-8px); }
}

@keyframes heroTitleGlow {
  0%, 100% { text-shadow: 0 4px 20px rgba(0, 237, 100, 0.25), 0 0 40px rgba(0, 237, 100, 0.08); }
  50%       { text-shadow: 0 4px 32px rgba(0, 237, 100, 0.55), 0 0 80px rgba(0, 237, 100, 0.22); }
}

.hero-title-main {
  animation:
    heroTitleFloat 4s ease-in-out infinite,
    heroTitleGlow  4s ease-in-out infinite;
  font-size: clamp(1.4rem, 3.5vw, 2.6rem);
  letter-spacing: 0.04em;
  line-height: 1.35;
}

@media (max-width: 767px) {
  .hero-title-main {
    font-size: clamp(1.05rem, 4.5vw, 1.5rem);
  }
}

@media (max-width: 425px) {
  .hero-title-main {
    font-size: clamp(0.95rem, 4vw, 1.25rem);
    letter-spacing: 0.02em;
  }
}

/* Section */
.section {
  padding: var(--space-2xl) 0;
  position: relative;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-label {
  font-family: var(--font-code);
  font-size: var(--text-xs);
  color: var(--mongodb-green);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: var(--space-sm);
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background: rgba(0, 237, 100, 0.1);
  border-radius: var(--radius-pill);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  margin-bottom: var(--space-md);
}

.section-dark .section-title {
  color: var(--pure-white);
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--teal-gray);
  max-width: 700px;
  margin: 0 auto;
}

/* Content Grid */
.content-grid {
  display: grid;
  gap: var(--space-lg);
}

.content-grid-2 {
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .content-grid-2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

.content-grid-3 {
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .content-grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .content-grid-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* Two Column Layout */
.two-column {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
  align-items: start;
}

@media (min-width: 1024px) {
  .two-column {
    grid-template-columns: 1fr 1fr;
  }
}

/* Footer */
.footer {
  background-color: var(--forest-black);
  color: var(--teal-gray);
  padding: var(--space-xl) 0;
  text-align: center;
  font-size: var(--text-sm);
}

.footer a {
  color: var(--mongodb-green);
  text-decoration: none;
  transition: color var(--transition-base);
}

.footer a:hover {
  color: var(--pure-white);
}

/* Responsive Utilities */
@media (max-width: 767px) {
  .hero-title {
    font-size: clamp(2rem, 6vw, 3rem);
  }
  
  .section-title {
    font-size: clamp(1.5rem, 4vw, 2rem);
  }
  
  .header-logo-text {
    display: none;
  }
  
  .header-nav {
    gap: var(--space-sm);
  }
  
  .header-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(0, 30, 43, 0.98);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: var(--space-lg);
    box-shadow: var(--shadow-lg);
    border-top: 1px solid rgba(0, 237, 100, 0.2);
  }
  
  .header-menu.active {
    display: flex;
  }
  
  .mobile-menu-toggle {
    display: block;
  }
  
  .nav-link {
    width: 100%;
    text-align: center;
    padding: var(--space-md);
  }
  
  .section {
    padding: var(--space-xl) 0;
  }
  
  .hero {
    padding: var(--space-2xl) 0 var(--space-xl);
  }
}

@media (max-width: 425px) {
  .hero-title {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
  }
  
  .section-title {
    font-size: clamp(1.25rem, 3vw, 1.75rem);
  }
  
  .theme-selector {
    flex-wrap: wrap;
  }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--light-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--teal-gray);
  border-radius: var(--radius-sm);
  transition: background var(--transition-base);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--mongodb-green);
}

/* Selection */
::selection {
  background-color: var(--mongodb-green);
  color: var(--forest-black);
}

/* Focus Visible */
*:focus-visible {
  outline: 2px solid var(--mongodb-green);
  outline-offset: 2px;
}

/* Smooth Scroll */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

/* Loading State */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.loading {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Fade In Animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

/* Scale In Animation */
@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.scale-in {
  animation: scaleIn 0.4s ease-out;
}