/* ============================================================
   audio.css — Audio Engineering page layout
   ============================================================ */

main { padding-top: 60px; }

/* ----------------------------------------------------------
   Page Hero
   ---------------------------------------------------------- */
.audio-hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  min-height: 420px;
  padding: 80px 60px;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-subtle);
}

.audio-hero__title-block { display: flex; flex-direction: column; gap: 20px; }

.audio-hero__subtitle {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  letter-spacing: 0.06em;
  line-height: 1.8;
}

/* Frequency Spectrum SVG */
.audio-hero__spectrum {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 160px;
  padding: 0 8px;
  justify-content: center;
}

.spectrum-bar {
  width: 5px;
  border-radius: 1px 1px 0 0;
  background: var(--accent-cyan);
  transform: scaleY(0);
  transform-origin: bottom;
  transition: transform 800ms cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.spectrum-bar.animate {
  transform: scaleY(1);
}

/* ----------------------------------------------------------
   Filter Bar
   ---------------------------------------------------------- */
.filter-bar {
  padding: 24px 60px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.filter-bar__label {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-right: 8px;
}

.filter-btn {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 6px 14px;
  border: 1px solid var(--border-mid);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition:
    background var(--transition-fast),
    color var(--transition-fast),
    border-color var(--transition-fast);
  min-height: 44px;
}

.filter-btn:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

.filter-btn.active {
  background: var(--accent-cyan);
  border-color: var(--accent-cyan);
  color: var(--bg-primary);
}

/* ----------------------------------------------------------
   Project Grid
   ---------------------------------------------------------- */
.project-section {
  padding: 60px;
  background: var(--bg-primary);
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 40px;
}

/* Wide cards span 2 columns */
.project-card--wide { grid-column: span 2; }

.project-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-mid);
  border-left: 3px solid var(--accent-cyan);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition:
    background var(--transition-fast),
    border-left-color var(--transition-fast),
    box-shadow var(--transition-fast);
  position: relative;
}

.project-card:hover {
  background: var(--bg-elevated);
  box-shadow: inset 3px 0 12px rgba(0, 200, 224, 0.08);
}

.project-card__top-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
}

.project-card__title-mono {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.project-card:hover .project-card__title-mono { color: var(--accent-cyan); }

.project-card__year {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--text-muted);
}

.project-card__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.4rem;
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

.project-card:hover .project-card__name { color: var(--accent-cyan); }

.project-card__embed {
  margin-top: 6px;
}

.project-card__embed-frame {
  aspect-ratio: 16 / 9;
  width: 100%;
  border: 1px dashed var(--border-mid);
  border-radius: var(--radius-sm);
  background:
    linear-gradient(to bottom right, rgba(0, 200, 224, 0.08), rgba(0, 255, 153, 0.04)),
    var(--bg-primary);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  text-align: center;
  padding: 10px;
}

.project-card__embed-frame--active {
  padding: 0;
  overflow: hidden;
  border-style: solid;
}

.project-card__embed-frame--ready {
  padding: 0;
  overflow: hidden;
}

.project-card__embed-trigger {
  all: unset;
  width: 100%;
  height: 100%;
  cursor: pointer;
  position: relative;
  display: block;
}

.project-card__embed-trigger:focus-visible {
  outline: 2px solid var(--accent-cyan);
  outline-offset: -2px;
}

.project-card__thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(0.88) contrast(1.06);
  transition: transform var(--transition-med), filter var(--transition-med);
}

.project-card__embed-trigger:hover .project-card__thumb,
.project-card__embed-trigger:focus-visible .project-card__thumb {
  transform: scale(1.02);
  filter: saturate(1) contrast(1.12);
}

.project-card__play-badge {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--accent-cyan);
  background: rgba(2, 6, 20, 0.72);
  color: var(--accent-cyan);
  box-shadow: var(--glow-cyan);
}

.project-card__iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

.project-card__embed-icon {
  width: 36px;
  height: 26px;
  border: 1px solid var(--accent-cyan);
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 0.8rem;
  box-shadow: var(--glow-cyan);
}

.project-card__embed-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.project-card__bottom-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: auto;
}

/* Filter hide state */
.project-card[data-hidden="true"] {
  opacity: 0.15;
  pointer-events: none;
  transition: opacity var(--transition-med);
}

/* ----------------------------------------------------------
   Signal Chain Section
   ---------------------------------------------------------- */
.signal-chain {
  padding: 100px 60px;
  background: var(--bg-secondary);
}

.signal-flow {
  display: flex;
  align-items: center;
  gap: 0;
  margin-top: 60px;
  position: relative;
}

.signal-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  flex: 1;
}

.signal-node__dot {
  width: 48px;
  height: 48px;
  border: 1px solid var(--accent-cyan);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-surface);
  position: relative;
  z-index: 1;
}

.signal-node__dot::after {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: var(--glow-cyan);
}

.signal-node__label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent-cyan);
}

.signal-node__desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-align: center;
  max-width: 160px;
  line-height: 1.6;
}

/* Connecting lines between nodes */
.signal-connector {
  flex: 0 0 40px;
  height: 1px;
  background: var(--border-mid);
  position: relative;
  overflow: hidden;
  align-self: center;
  margin-bottom: 64px; /* align with dots */
}

.signal-connector::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(to right, transparent, var(--accent-cyan), transparent);
  animation: signal-travel 2.4s linear infinite;
}

@keyframes signal-travel {
  0%   { left: -100%; }
  100% { left: 100%; }
}

/* ----------------------------------------------------------
   Arsenal Section
   ---------------------------------------------------------- */
.arsenal {
  padding: 100px 60px;
  background: var(--bg-primary);
}

.arsenal__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-top: 60px;
}

.arsenal__col-label {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.arsenal__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* ----------------------------------------------------------
   Responsive
   ---------------------------------------------------------- */
@media (max-width: 1024px) {
  .audio-hero { grid-template-columns: 1fr; padding: 60px 40px; }
  .audio-hero__spectrum { display: none; }
  .project-section { padding: 60px 40px; }
  .project-grid { grid-template-columns: repeat(2, 1fr); }
  .project-card--wide { grid-column: span 1; }
  .signal-chain { padding: 80px 40px; }
  .arsenal { padding: 80px 40px; }
  .arsenal__grid { grid-template-columns: 1fr; gap: 32px; }
  .filter-bar { padding: 20px 40px; }
}

@media (max-width: 768px) {
  .audio-hero { padding: 40px 20px; }
  .project-section { padding: 40px 20px; }
  .project-grid { grid-template-columns: 1fr; }
  .signal-flow {
    flex-direction: column;
    gap: 32px;
  }
  .signal-connector {
    width: 1px;
    height: 32px;
    flex: 0 0 32px;
    margin-bottom: 0;
    margin-right: 0;
  }
  @keyframes signal-travel {
    0%   { top: -100%; left: 0; }
    100% { top: 100%; left: 0; }
  }
  .signal-connector::after {
    top: -100%;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, transparent, var(--accent-cyan), transparent);
  }
  .arsenal { padding: 60px 20px; }
  .filter-bar { padding: 16px 20px; }
}