/* Portfolio Section */
.portfolio-section {
  padding: var(--spacing-3xl) 0;
  /* Transparent — the continuous page gradient on <body> shows through.
     The subtle dot pattern in ::before still sits on top. */
  background: transparent;
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
}

.portfolio-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url('data:image/svg+xml,<svg width="80" height="80" viewBox="0 0 80 80" xmlns="http://www.w3.org/2000/svg"><g fill="none" fill-rule="evenodd"><g fill="%23334155" fill-opacity="0.03"><circle cx="40" cy="40" r="2"/><circle cx="20" cy="20" r="1"/><circle cx="60" cy="20" r="1"/><circle cx="20" cy="60" r="1"/><circle cx="60" cy="60" r="1"/></g></g></svg>') repeat;
  pointer-events: none;
  z-index: 0;
}

.portfolio-section .container { position: relative; z-index: 2; }

.portfolio-section .section-header {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}
.portfolio-section .section-title {
  font-size: var(--font-size-3xl);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
  letter-spacing: -0.02em;
}
.portfolio-section .section-subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
}

/* Screen-reader-only (keeps descriptions for SEO/a11y) */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============================================
   Marquee — two rows scrolling opposite ways
   ============================================ */
.portfolio-marquee {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
  padding: var(--spacing-xl) 0;
  /* fade the left/right edges so cards melt away */
  -webkit-mask-image: linear-gradient(90deg, transparent 0, #000 7%, #000 93%, transparent 100%);
  mask-image: linear-gradient(90deg, transparent 0, #000 7%, #000 93%, transparent 100%);
}

.marquee-row {
  overflow: visible;
}

.marquee-track {
  display: flex;
  width: max-content;
  will-change: transform;
}

/* Each row scrolls a different way. Pausing is driven by JS (the .is-paused
 * class) rather than :hover, so a stationary cursor that the section simply
 * scrolls underneath doesn't freeze the marquee — only an actual pointer
 * move onto a row pauses it. :focus-within keeps keyboard users covered. */
.marquee-row--ltr .marquee-track { animation: marqueeLeft  46s linear infinite; }
.marquee-row--rtl .marquee-track { animation: marqueeRight 46s linear infinite; }

.marquee-row.is-paused .marquee-track,
.marquee-row:focus-within .marquee-track {
  animation-play-state: paused;
}

@keyframes marqueeLeft {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}
@keyframes marqueeRight {
  from { transform: translateX(-50%); }
  to   { transform: translateX(0); }
}

/* ============================================
   Flip tile (square)
   ============================================ */
.portfolio-card {
  position: relative;
  perspective: 1400px;
  cursor: pointer;
}

/* Marquee context — fixed square units with the gap baked in (seamless loop) */
.marquee-track .portfolio-card {
  flex: 0 0 auto;
  width: 230px;
  height: 230px;
  margin-right: var(--spacing-lg);
}

/* Gallery context — fluid square grid items */
.gallery-grid .portfolio-card {
  width: 100%;
  aspect-ratio: 1 / 1;
}

/* The flipping element */
.card-inner {
  position: absolute;
  inset: 0;
  transform-style: preserve-3d;
  transition: transform 0.7s var(--ease-out-expo);
  border-radius: var(--border-radius-lg);
}
.portfolio-card:hover .card-inner,
.portfolio-card:focus-within .card-inner {
  transform: rotateY(180deg);
}

/* Front + back faces */
.card-face {
  position: absolute;
  inset: 0;
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  box-shadow:
    0 12px 28px rgba(45, 55, 72, 0.18),
    0 3px 8px rgba(45, 55, 72, 0.12);
  transition: box-shadow 0.4s ease;
}
.portfolio-card:hover .card-face {
  box-shadow:
    0 20px 40px rgba(49, 130, 206, 0.28),
    0 5px 12px rgba(45, 55, 72, 0.16);
}

/* Front — clean square thumbnail */
.card-front { background: #0f172a; }
.card-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.card-front::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--border-radius-lg);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.10);
  pointer-events: none;
}

/* Title label on the front — only used on touch devices (no hover/flip) */
.card-front-label {
  display: none;
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 2.2rem var(--spacing-md) var(--spacing-md);
  background: linear-gradient(to top, rgba(15, 23, 42, 0.92) 10%, rgba(15, 23, 42, 0));
  color: #fff;
  font-weight: 700;
  font-size: var(--font-size-sm);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.4);
  z-index: 2;
}

/* Back — title, tags, actions */
.card-back {
  transform: rotateY(180deg);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  background: linear-gradient(145deg, #0f172a 0%, #14365a 55%, #1e5b96 100%);
  color: #fff;
}
.card-back::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--border-radius-lg);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.12), inset 0 0 0 1px rgba(255,255,255,0.06);
  pointer-events: none;
}
.card-back .card-title {
  font-size: var(--font-size-lg);
  font-weight: 800;
  color: #fff;
  margin: 0;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

/* Card Tags */
.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
}
.tag {
  padding: 2px 9px;
  background: rgba(255, 255, 255, 0.18);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.32);
  border-radius: var(--border-radius-full);
  font-size: var(--font-size-xs);
  font-weight: 600;
  letter-spacing: 0.3px;
  backdrop-filter: blur(4px);
}

/* Back actions row */
.card-back-actions {
  margin-top: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-sm);
}
.card-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-weight: 700;
  font-size: var(--font-size-sm);
  letter-spacing: 0.3px;
  color: #fff;
}
.card-cta i { transition: transform 0.3s var(--ease-out-quart); }
.portfolio-card:hover .card-cta i { transform: translateX(4px); }

/* GitHub button on the back face */
.action-btn.tile-gh {
  flex-shrink: 0;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.4);
  color: #fff;
  text-decoration: none;
  transition: transform 0.25s ease, background 0.25s ease, color 0.25s ease;
}
.action-btn.tile-gh:hover {
  background: #fff;
  color: #1a202c;
  transform: scale(1.1) rotate(6deg);
}

/* Touch devices: no hover, so don't flip — show the title label instead */
@media (hover: none) {
  .card-inner { transform: none !important; }
  .card-front-label { display: block; }
}

/* Reduced motion: stop the marquee, let users scroll the rows by hand */
@media (prefers-reduced-motion: reduce) {
  .marquee-track { animation: none !important; }
  .marquee-row {
    overflow-x: auto;
    scroll-snap-type: x proximity;
  }
  .card-inner { transition: none; }
  .portfolio-card:hover .card-inner,
  .portfolio-card:focus-within .card-inner { transform: none; }
  .card-front-label { display: block; }
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .portfolio-section { min-height: auto; padding: var(--spacing-2xl) 0; }
  .marquee-track .portfolio-card {
    width: 180px;
    height: 180px;
    margin-right: var(--spacing-md);
  }
  .card-back { padding: var(--spacing-sm); }
  .card-back .card-title { font-size: var(--font-size-base); }
  .marquee-row--ltr .marquee-track { animation-duration: 34s; }
  .marquee-row--rtl .marquee-track { animation-duration: 34s; }
}

@media (max-width: 480px) {
  .marquee-track .portfolio-card { width: 150px; height: 150px; }
}

/* ============================================
   View All button + filterable gallery
   ============================================ */
.portfolio-cta {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-xl);
}

.view-all-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  background: var(--accent-gradient-cool);
  color: white;
  border: none;
  border-radius: var(--border-radius-full);
  font-weight: 700;
  font-size: var(--font-size-base);
  cursor: pointer;
  transition: transform 0.3s var(--ease-out-quart), box-shadow 0.3s ease;
  letter-spacing: 0.4px;
  box-shadow: 0 8px 24px rgba(49, 130, 206, 0.3);
}
.view-all-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 36px rgba(49, 130, 206, 0.4);
}
.view-all-btn i { transition: transform 0.3s ease; }
.view-all-btn[aria-expanded="true"] i { transform: rotate(180deg); }

.portfolio-gallery {
  position: relative;
  z-index: 2;
  margin-top: var(--spacing-2xl);
  animation: galleryReveal 0.5s var(--ease-out-quart);
}
.portfolio-gallery[hidden] { display: none; }

@keyframes galleryReveal {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* Filters */
.portfolio-filters {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-2xl);
  padding: 0 var(--spacing-md);
}
.filter-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: 0.55rem 1.1rem;
  background: rgba(255, 255, 255, 0.9);
  border: 1.5px solid transparent;
  border-radius: var(--border-radius-full);
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.3s var(--ease-out-quart);
  backdrop-filter: blur(10px);
  font-size: var(--font-size-sm);
  letter-spacing: 0.2px;
}
.filter-btn:hover {
  background: white;
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(49, 130, 206, 0.18);
}
.filter-btn.active {
  background: var(--accent-gradient-cool);
  border-color: transparent;
  color: white;
  box-shadow: 0 8px 24px rgba(49, 130, 206, 0.35);
}
.filter-btn i { font-size: 0.95rem; }

/* Static grid */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}
.gallery-grid .portfolio-card.is-hidden { display: none; }

@media (max-width: 768px) {
  .gallery-grid { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: var(--spacing-md); }
  .filter-btn { padding: 0.4rem 0.8rem; font-size: var(--font-size-xs); }
}
@media (max-width: 480px) {
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
}
