/* ================================================
   LectureVault — Landing Page Styles
   Dark theme · Glass-morphism · Polished animations
   ================================================ */

@import url("https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500;600&display=swap");

/* ----- Design Tokens ----- */
:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #111118;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-glass: rgba(255, 255, 255, 0.05);

  --accent: #00e5ff;
  --accent-dim: rgba(0, 229, 255, 0.15);
  --purple: #7c3aed;
  --purple-dim: rgba(124, 58, 237, 0.15);
  --gradient: linear-gradient(135deg, var(--accent), var(--purple));

  --text-primary: #e8e8ed;
  --text-secondary: #8b8b9e;
  --text-muted: #555566;

  --border: rgba(255, 255, 255, 0.06);
  --border-hover: rgba(255, 255, 255, 0.12);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 16px 64px rgba(0, 0, 0, 0.45);

  --font-body: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;

  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ----- Reset & Base ----- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  scroll-behavior: smooth;
  font-size: 16px;
}
body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}
img {
  max-width: 100%;
  display: block;
}
button {
  cursor: pointer;
  font: inherit;
  border: none;
  background: none;
}
ul {
  list-style: none;
}

/* ----- Utility ----- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}
.section {
  padding: 120px 0;
  position: relative;
}
.section-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 6px 16px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.section-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
}
.section-title span {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-desc {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 600px;
  line-height: 1.7;
}
.section-header {
  text-align: center;
  margin-bottom: 64px;
}
.section-header .section-desc {
  margin: 0 auto;
}

/* ----- Scroll Reveal ----- */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition:
    opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1),
    transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 {
  transition-delay: 0.1s;
}
.reveal-delay-2 {
  transition-delay: 0.2s;
}
.reveal-delay-3 {
  transition-delay: 0.3s;
}
.reveal-delay-4 {
  transition-delay: 0.4s;
}
.reveal-delay-5 {
  transition-delay: 0.5s;
}

/* =====================  NAVBAR  ===================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 16px 0;
  transition:
    background var(--transition),
    box-shadow var(--transition),
    padding var(--transition);
}
.navbar.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 var(--border);
  padding: 10px 0;
}
.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.25rem;
}
.nav-logo .logo-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}
.nav-links {
  display: flex;
  gap: 32px;
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  transition: color var(--transition);
}
.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient);
  border-radius: 2px;
  transition: width var(--transition);
}
.nav-links a:hover {
  color: var(--text-primary);
}
.nav-links a:hover::after {
  width: 100%;
}
.nav-cta {
  padding: 8px 20px;
  border-radius: 999px;
  font-size: 0.875rem;
  font-weight: 600;
  background: var(--gradient);
  color: #000;
  transition:
    transform var(--transition),
    box-shadow var(--transition);
}
.nav-cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(0, 229, 255, 0.3);
}
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
}
.mobile-toggle span {
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* =====================  HERO  ===================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}
#particles-canvas {
  position: absolute;
  inset: 0;
  z-index: 0;
}

/* Gradient orbs */
.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.4;
  pointer-events: none;
}
.hero::before {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 229, 255, 0.25), transparent 70%);
  top: -100px;
  right: -100px;
  animation: float-orb 8s ease-in-out infinite alternate;
}
.hero::after {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(124, 58, 237, 0.2), transparent 70%);
  bottom: -80px;
  left: -80px;
  animation: float-orb 10s ease-in-out infinite alternate-reverse;
}
@keyframes float-orb {
  0% {
    transform: translate(0, 0);
  }
  100% {
    transform: translate(30px, -40px);
  }
}

.hero-content {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: 64px;
}
.hero-text {
  flex: 1;
}
.hero-visual {
  flex: 1;
  display: flex;
  justify-content: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: 999px;
  background: var(--bg-glass);
  border: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
  animation: fadeInUp 0.8s ease both;
}
.hero-badge .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #22c55e;
  animation: pulse-dot 2s ease-in-out infinite;
}
@keyframes pulse-dot {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.4;
  }
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 900;
  line-height: 1.05;
  margin-bottom: 20px;
  animation: fadeInUp 0.8s ease 0.15s both;
}
.hero h1 .gradient-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 520px;
  margin-bottom: 36px;
  animation: fadeInUp 0.8s ease 0.3s both;
}
.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease 0.45s both;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition);
}
.btn-primary {
  background: var(--gradient);
  color: #000;
  box-shadow: 0 0 0 0 rgba(0, 229, 255, 0);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 229, 255, 0.25);
}
.btn-secondary {
  background: var(--bg-glass);
  color: var(--text-primary);
  border: 1px solid var(--border);
}
.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}
.btn svg {
  width: 18px;
  height: 18px;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Hero terminal mock */
.hero-terminal {
  width: 100%;
  max-width: 440px;
  background: rgba(17, 17, 24, 0.9);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  animation: fadeInUp 0.8s ease 0.5s both;
}
.terminal-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  background: rgba(255, 255, 255, 0.03);
  border-bottom: 1px solid var(--border);
}
.terminal-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.terminal-dot.red {
  background: #ff5f57;
}
.terminal-dot.yellow {
  background: #febc2e;
}
.terminal-dot.green {
  background: #28c840;
}
.terminal-title {
  margin-left: auto;
  margin-right: auto;
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.terminal-body {
  padding: 20px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.9;
}
.terminal-body .line {
  display: flex;
  gap: 8px;
}
.terminal-body .prompt {
  color: var(--accent);
  white-space: nowrap;
}
.terminal-body .cmd {
  color: var(--text-primary);
}
.terminal-body .output {
  color: var(--text-secondary);
  padding-left: 20px;
  margin-top: 2px;
}
.terminal-body .success {
  color: #22c55e;
}
.terminal-body .cursor {
  display: inline-block;
  width: 8px;
  height: 16px;
  background: var(--accent);
  animation: blink 1s step-end infinite;
  vertical-align: text-bottom;
  margin-left: 2px;
}
@keyframes blink {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0;
  }
}

/* Stats bar */
.stats-bar {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  margin-top: 80px;
  padding: 32px;
  background: var(--bg-glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  position: relative;
  z-index: 1;
  animation: fadeInUp 0.8s ease 0.6s both;
}
.stat-item {
  text-align: center;
}
.stat-value {
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.stat-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* =====================  FEATURES  ===================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  padding: 36px 28px;
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient);
  opacity: 0;
  transition: opacity var(--transition);
}
.feature-card:hover {
  background: var(--bg-glass);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.feature-card:hover::before {
  opacity: 1;
}
.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}
.feature-icon.cyan {
  background: var(--accent-dim);
  color: var(--accent);
}
.feature-icon.purple {
  background: var(--purple-dim);
  color: var(--purple);
}
.feature-icon.green {
  background: rgba(34, 197, 94, 0.12);
  color: #22c55e;
}
.feature-icon.orange {
  background: rgba(251, 146, 60, 0.12);
  color: #fb923c;
}
.feature-icon.pink {
  background: rgba(236, 72, 153, 0.12);
  color: #ec4899;
}
.feature-icon.blue {
  background: rgba(59, 130, 246, 0.12);
  color: #3b82f6;
}
.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}
.feature-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.65;
}

/* =====================  HOW IT WORKS  ===================== */
.steps-container {
  display: flex;
  gap: 32px;
  position: relative;
}
.steps-container::before {
  content: "";
  position: absolute;
  top: 36px;
  left: 36px;
  right: 36px;
  height: 2px;
  background: var(--border);
  z-index: 0;
}
.step-card {
  flex: 1;
  text-align: center;
  position: relative;
  z-index: 1;
  padding: 32px 24px;
}
.step-number {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--bg-secondary);
  border: 2px solid var(--border);
  margin: 0 auto 24px;
  transition: all var(--transition);
}
.step-card:hover .step-number {
  border-color: var(--accent);
  box-shadow: 0 0 30px var(--accent-dim);
}
.step-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
}
.step-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
}
.step-code {
  margin-top: 16px;
  padding: 10px 16px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  display: inline-block;
}

/* =====================  COMMANDS  ===================== */
.commands-terminal {
  max-width: 800px;
  margin: 0 auto;
  background: rgba(17, 17, 24, 0.9);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.commands-body {
  padding: 28px 32px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 2;
}
.cmd-group-title {
  color: var(--accent);
  font-weight: 600;
  margin-top: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.cmd-group-title:first-child {
  margin-top: 0;
}
.cmd-entry {
  display: flex;
  gap: 12px;
  padding-left: 20px;
}
.cmd-name {
  color: var(--text-primary);
  min-width: 140px;
  font-weight: 500;
}
.cmd-sep {
  color: var(--text-muted);
}
.cmd-desc {
  color: var(--text-secondary);
}

/* =====================  TECH STACK  ===================== */
.tech-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
}
.tech-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border);
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition);
}
.tech-badge:hover {
  background: var(--bg-glass);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}
.tech-badge img {
  width: 22px;
  height: 22px;
}
.tech-badge svg {
  width: 22px;
  height: 22px;
  fill: currentColor;
}

/* =====================  CTA  ===================== */
.cta-section {
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-section::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(
    ellipse at center,
    rgba(0, 229, 255, 0.06),
    transparent 70%
  );
  pointer-events: none;
}
.cta-section .section-title {
  margin-bottom: 20px;
}
.cta-section .section-desc {
  margin: 0 auto 36px;
}

/* =====================  FOOTER  ===================== */
.footer {
  padding: 48px 0 32px;
  border-top: 1px solid var(--border);
}
.footer-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
}
.footer-links {
  display: flex;
  gap: 24px;
}
.footer-links a {
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: color var(--transition);
}
.footer-links a:hover {
  color: var(--accent);
}
.footer-copy {
  text-align: center;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* =====================  MOBILE NAV OVERLAY  ===================== */
.mobile-nav {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: rgba(10, 10, 15, 0.95);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.4s ease,
    visibility 0.4s ease;
}
.mobile-nav.open {
  opacity: 1;
  visibility: visible;
}
.mobile-nav-links {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
}
.mobile-nav-links a {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
  transition: color var(--transition);
}
.mobile-nav-links a:hover {
  color: var(--accent);
}
.mobile-nav-close {
  position: absolute;
  top: 24px;
  right: 24px;
  font-size: 1.5rem;
  color: var(--text-primary);
  background: none;
  border: none;
  cursor: pointer;
}

/* =====================  RESPONSIVE  ===================== */
@media (max-width: 1024px) {
  .hero-content {
    flex-direction: column;
    text-align: center;
  }
  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }
  .hero-actions {
    justify-content: center;
  }
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}
@media (max-width: 768px) {
  .section {
    padding: 80px 0;
  }
  .nav-links,
  .nav-cta {
    display: none;
  }
  .mobile-toggle {
    display: flex;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .steps-container {
    flex-direction: column;
  }
  .steps-container::before {
    display: none;
  }
  .stats-bar {
    gap: 28px;
  }
  .stat-item {
    flex: 1 1 120px;
  }
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
  .commands-body {
    padding: 20px;
    font-size: 0.78rem;
  }
  .cmd-entry {
    flex-direction: column;
    gap: 4px;
    padding-left: 12px;
  }
  .cmd-name {
    min-width: auto;
  }
}
@media (max-width: 480px) {
  .section {
    padding: 60px 0;
  }
  .container {
    padding: 0 16px;
  }
  .hero h1 {
    font-size: 2.2rem;
  }
  .btn {
    padding: 12px 22px;
    font-size: 0.88rem;
  }
  .stats-bar {
    flex-direction: column;
    align-items: center;
    gap: 20px;
  }
}

/* ----- Reduced Motion ----- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}