/* ===== HOME PAGE STYLES ===== */

.hero-section {
  position: relative;
  min-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 0 80px;
  overflow: hidden;
}

.hero-bg-grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(var(--border-color) 1px, transparent 1px),
                    linear-gradient(90deg, var(--border-color) 1px, transparent 1px);
  background-size: 50px 50px;
  opacity: 0.2;
  mask-image: radial-gradient(circle at center, black, transparent 80%);
  -webkit-mask-image: radial-gradient(circle at center, black, transparent 80%);
  z-index: 0;
}

.hero-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(100px);
  z-index: 0;
  opacity: 0.15;
}

.hero-glow-1 {
  background: var(--lpf-color);
  top: -200px;
  left: -200px;
}

.hero-glow-2 {
  background: var(--hpf-color);
  bottom: -200px;
  right: -200px;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 6px 16px;
  border-radius: 40px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-green);
  box-shadow: 0 0 10px var(--accent-green);
}

.hero-title {
  font-size: clamp(3rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.hero-subtitle {
  font-size: 1.1rem;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 40px;
  max-width: 600px;
  margin-inline: auto;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1.1rem;
  border-radius: 8px;
}

.btn-ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid transparent;
}

.btn-ghost:hover {
  background: var(--bg-card);
  border-color: var(--border-color);
}

/* Animations */
.animate-hero {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
  animation-delay: var(--d);
}

@keyframes fadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Hero Wave */
.hero-wave {
  margin-top: 60px;
  height: 100px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.wave-bars {
  display: flex;
  align-items: center;
  gap: 6px;
  height: 100px;
}

.wave-bars span {
  display: block;
  width: 8px;
  background: linear-gradient(to top, var(--lpf-color), var(--hpf-color));
  border-radius: 4px;
  height: var(--h);
  animation: wavePulse 2s ease-in-out infinite alternate;
  animation-delay: var(--d);
  opacity: 0.7;
}

@keyframes wavePulse {
  0% { transform: scaleY(0.4); opacity: 0.3; }
  100% { transform: scaleY(1); opacity: 1; }
}

/* Features Section */
.features-section {
  padding: 100px 0;
  background: var(--bg-secondary);
}

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  color: var(--lpf-color);
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 24px;
}

.feature-card {
  display: block;
  text-decoration: none;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 32px 24px;
  border-radius: 16px;
  transition: all 0.3s ease;
  color: var(--text-primary);
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
  box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

[data-theme="light"] .feature-card:hover {
  box-shadow: 0 10px 25px rgba(0,0,0,0.05);
}

.feature-icon-wrap {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 24px;
}

.blue-icon { background: rgba(59, 130, 246, 0.1); color: #3b82f6; }
.cyan-icon { background: rgba(6, 182, 212, 0.1); color: #06b6d4; }
.purple-icon { background: rgba(139, 92, 246, 0.1); color: #8b5cf6; }
.green-icon { background: rgba(16, 185, 129, 0.1); color: #10b981; }

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 16px;
}

.card-arrow {
  color: var(--text-muted);
  font-weight: 700;
  transition: transform 0.2s ease, color 0.2s;
  display: inline-block;
}

.feature-card:hover .card-arrow {
  transform: translateX(5px);
  color: var(--lpf-color);
}

/* Filter Types Details */
.filter-section {
  padding: 100px 0;
}

.filter-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.filter-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  padding: 40px;
  position: relative;
  overflow: hidden;
}

.lpf-card {
  box-shadow: inset 0 0 100px rgba(6, 182, 212, 0.05);
}

.hpf-card {
  box-shadow: inset 0 0 100px rgba(139, 92, 246, 0.05);
}

.filter-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.filter-label {
  font-size: 0.75rem;
  font-weight: 800;
  padding: 4px 12px;
  border-radius: 20px;
  letter-spacing: 0.05em;
}

.lpf-label {
  background: rgba(6, 182, 212, 0.15);
  color: #06b6d4;
}

.hpf-label {
  background: rgba(139, 92, 246, 0.15);
  color: #8b5cf6;
}

.filter-emoji {
  font-size: 2rem;
}

.filter-card h3 {
  font-size: 2rem;
  margin-bottom: 16px;
}

.filter-card p {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 24px;
}

.filter-formula {
  background: var(--bg-primary);
  padding: 16px;
  border-radius: 8px;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-primary);
  border-left: 3px solid transparent;
  margin-bottom: 32px;
}

.lpf-card .filter-formula {
  border-color: #06b6d4;
}

.hpf-card .filter-formula {
  border-color: #8b5cf6;
}

/* Mini visual response bars */
.filter-response {
  height: 60px;
  display: flex;
  gap: 4px;
  align-items: flex-end;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 4px;
}

.resp-bar {
  flex: 1;
  background: var(--border-color);
  border-radius: 4px 4px 0 0;
  transition: all 0.3s;
}

.lpf-card:hover .resp-bar:not(.stopband-bar):not(.transition-bar) {
  background: #06b6d4;
}
.lpf-card:hover .transition-bar {
  background: rgba(6, 182, 212, 0.4);
}

.hpf-card:hover .resp-bar:not(.stopband-bar):not(.transition-bar) {
  background: #8b5cf6;
}
.hpf-card:hover .transition-bar {
  background: rgba(139, 92, 246, 0.4);
}

/* CTA Section */
.cta-section {
  padding: 80px 0 120px;
}

.cta-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  padding: 60px 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-glow {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(6, 182, 212, 0.1), rgba(139, 92, 246, 0.1));
  z-index: 0;
}

.cta-box h2 {
  position: relative;
  z-index: 1;
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.cta-box p {
  position: relative;
  z-index: 1;
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 32px;
  max-width: 500px;
  margin-inline: auto;
}

.cta-actions {
  position: relative;
  z-index: 1;
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

@media (max-width: 768px) {
  .hero-title { font-size: 2.5rem; }
  .filter-cards { grid-template-columns: 1fr; }
  .hero-actions, .cta-actions { flex-direction: column; }
  .btn-lg { width: 100%; text-align: center; }
}