/* ============================================
   Portfolio Project Page — Refined
   ============================================ */

/* Back Navigation */
.back-nav {
  position: fixed;
  top: 1.5rem;
  left: 1.5rem;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  padding: 10px 18px;
  border-radius: var(--border-radius-full);
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 600;
  font-size: var(--font-size-sm);
  transition: all 0.25s var(--ease-out-quart);
  border: 1px solid var(--border-color);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  box-shadow: 0 4px 16px var(--shadow-soft);
}

.back-nav:hover {
  background: white;
  color: var(--accent-primary);
  box-shadow: 0 8px 22px rgba(49, 130, 206, 0.18);
  transform: translateX(-4px);
  padding-left: 22px;
}
.back-nav i { transition: transform 0.25s ease; }
.back-nav:hover i { transform: translateX(-2px); }

/* Reading progress bar (created by JS but styled here) */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  width: 0;
  background: var(--accent-gradient);
  z-index: 1001;
  transition: width 0.15s linear;
  box-shadow: 0 0 12px rgba(49, 130, 206, 0.4);
}

/* ---- Project Header ---- */
.project-header {
  padding: 6.5rem 0 3rem;
  background: var(--bg-primary);
  position: relative;
  overflow: hidden;
  isolation: isolate;
}

/* Soft aurora behind header */
.project-header::before,
.project-header::after {
  content: '';
  position: absolute;
  z-index: -1;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.45;
  pointer-events: none;
}
.project-header::before {
  width: 460px; height: 460px;
  top: -160px; left: -140px;
  background: radial-gradient(circle, var(--accent-primary), transparent 65%);
}
.project-header::after {
  width: 380px; height: 380px;
  top: -80px; right: -120px;
  background: radial-gradient(circle, var(--accent-coral), transparent 65%);
}

.project-header .container { max-width: 1200px; position: relative; z-index: 1; }

.project-header .project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
  opacity: 0;
  animation: revealUp 0.7s var(--ease-out-quart) 0.05s forwards;
}

.project-header .tag {
  display: inline-flex;
  align-items: center;
  padding: 5px 13px;
  font-size: var(--font-size-xs);
  font-weight: 600;
  letter-spacing: 0.3px;
  border-radius: var(--border-radius-full);
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(8px);
  color: var(--accent-primary-dark);
  border: 1px solid rgba(49, 130, 206, 0.2);
  transition: transform 0.25s var(--ease-out-quart), box-shadow 0.25s ease;
}
.project-header .tag:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(49,130,206,0.15);
}

.project-header .project-title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.1;
  color: var(--text-primary);
  margin: 0 0 1rem 0;
  letter-spacing: -0.025em;
  opacity: 0;
  animation: revealUp 0.7s var(--ease-out-quart) 0.15s forwards;
}

.project-header .project-subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 720px;
  margin: 0;
  opacity: 0;
  animation: revealUp 0.7s var(--ease-out-quart) 0.25s forwards;
}

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

/* ---- Main Content Area ---- */
.project-content {
  padding: 3rem 0 5rem;
  background: linear-gradient(180deg, #f7f7f5 0%, #f0f1f4 100%);
  position: relative;
}

.content-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 2.5rem;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  align-items: start;
}

.main-content {
  background: #fff;
  border-radius: var(--border-radius-xl);
  padding: 2.75rem;
  border: 1px solid rgba(45,55,72,0.06);
  box-shadow: 0 10px 30px var(--shadow-soft);
}

/* ---- Content Sections ---- */
.content-section {
  margin-bottom: 2.5rem;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.7s var(--ease-out-quart), transform 0.7s var(--ease-out-quart);
}
.content-section.in-view {
  opacity: 1;
  transform: translateY(0);
}
.content-section:last-child { margin-bottom: 0; }

.content-section h2 {
  font-size: var(--font-size-2xl);
  font-weight: 800;
  color: var(--text-primary);
  margin: 0 0 1.25rem 0;
  padding-bottom: 0.85rem;
  letter-spacing: -0.015em;
  position: relative;
}
.content-section h2::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  height: 3px;
  width: 48px;
  background: var(--accent-gradient);
  border-radius: 3px;
}

.content-text {
  font-size: var(--font-size-base);
  line-height: 1.75;
  color: var(--text-secondary);
}

.content-text p { margin-bottom: 1.25rem; }

.content-text h3 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--text-primary);
  margin: 1.75rem 0 0.75rem 0;
}

.content-text ul,
.content-text ol {
  margin: 1rem 0;
  padding-left: 1.5rem;
}

.content-text li { margin-bottom: 0.4rem; }

.content-text a {
  color: var(--accent-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 2px;
  text-decoration-color: rgba(49,130,206,0.35);
  transition: text-decoration-color 0.2s ease, color 0.2s ease;
}
.content-text a:hover {
  color: var(--accent-primary-dark);
  text-decoration-color: var(--accent-primary-dark);
}

/* ---- Inline code ---- */
.content-text code {
  background: #f1f5f9;
  color: #be185d;
  padding: 2px 7px;
  border-radius: 5px;
  font-family: var(--font-mono);
  font-size: 0.88em;
  border: 1px solid rgba(45,55,72,0.06);
}

/* ---- Code blocks: pre + pre>code ----
   Critical fix: reset the inline-code background/color when nested inside <pre>. */
.content-text pre {
  background: #0f172a;
  color: #e2e8f0;
  padding: 1.5rem 1.25rem 1.25rem;
  border-radius: var(--border-radius-lg);
  overflow-x: auto;
  margin: 1.5rem 0;
  font-size: var(--font-size-sm);
  line-height: 1.65;
  font-family: var(--font-mono);
  position: relative;
  border: 1px solid #1e293b;
  box-shadow: 0 10px 30px rgba(15,23,42,0.25);
}

.content-text pre code,
.content-text pre code * {
  background: transparent !important;
  color: inherit;
  padding: 0;
  border: 0;
  border-radius: 0;
  font-family: var(--font-mono);
  font-size: inherit;
  white-space: pre;
}

/* Top bar of every code block: dots + optional language label */
.content-text pre::before {
  content: '';
  position: absolute;
  top: 14px;
  left: 18px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #ff5f57;
  box-shadow:
    20px 0 0 #ffbd2e,
    40px 0 0 #28ca42;
}
.content-text pre {
  padding-top: 2.6rem;
}

.content-text pre[data-lang]::after {
  content: attr(data-lang);
  position: absolute;
  top: 12px;
  right: 56px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: #64748b;
  font-family: var(--font-mono);
}

/* Copy button injected by JS */
.copy-code-btn {
  position: absolute;
  top: 8px;
  right: 10px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #e2e8f0;
  padding: 6px 10px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.25s ease;
  font-size: 12px;
  font-family: var(--font-family);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.copy-code-btn:hover {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.3);
}
.copy-code-btn.copied {
  background: rgba(34, 197, 94, 0.2);
  border-color: rgba(34, 197, 94, 0.4);
  color: #86efac;
}

/* ---- Video Embed ---- */
.video-wrapper {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  margin: 1.25rem 0;
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.15);
}

.video-wrapper iframe,
.video-wrapper video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: none;
}

.video-caption {
  font-style: italic;
  color: #94a3b8;
  text-align: center;
  margin-top: 0.5rem;
  font-size: var(--font-size-sm);
}

/* ---- Image Gallery ---- */
.image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.gallery-item {
  position: relative;
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.35s var(--ease-out-quart), box-shadow 0.35s ease;
  border: 1px solid var(--border-color);
}

.gallery-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 16px 36px rgba(49,130,206,0.18);
}

.gallery-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
  transition: transform 0.5s var(--ease-out-quart);
}

.gallery-item:hover img { transform: scale(1.06); }

.gallery-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(49,130,206,0.65), rgba(229,62,62,0.55));
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.gallery-item:hover .gallery-overlay { opacity: 1; }
.gallery-overlay i { color: #fff; font-size: 1.6rem; }

/* ---- Sidebar (sticky on desktop) ---- */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: sticky;
  top: 2rem;
  align-self: start;
}

.sidebar-card {
  background: #fff;
  border-radius: var(--border-radius-xl);
  padding: 1.5rem;
  border: 1px solid rgba(45,55,72,0.06);
  box-shadow: 0 6px 20px var(--shadow-soft);
  transition: transform 0.3s var(--ease-out-quart), box-shadow 0.3s ease;
}
.sidebar-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(49,130,206,0.12);
}

.sidebar-card h3 {
  font-size: var(--font-size-base);
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 1rem 0;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border-color);
  position: relative;
}
.sidebar-card h3::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 28px;
  height: 2px;
  background: var(--accent-gradient);
  border-radius: 2px;
}

/* Project details */
.project-details {
  display: flex;
  flex-direction: column;
}

.detail-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.65rem 0;
  border-bottom: 1px solid #f1f5f9;
  font-size: var(--font-size-sm);
}
.detail-item:last-child { border-bottom: none; }

.detail-item strong {
  color: #94a3b8;
  font-weight: 600;
}

.detail-item span {
  color: var(--text-primary);
  font-weight: 600;
}

/* Tech stack */
.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.tech-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.75rem;
  background: rgba(49, 130, 206, 0.06);
  border: 1px solid rgba(49, 130, 206, 0.15);
  border-radius: var(--border-radius-full);
  font-weight: 600;
  font-size: var(--font-size-sm);
  color: var(--text-primary);
  transition: all 0.25s var(--ease-out-quart);
}
.tech-item:hover {
  background: var(--accent-primary);
  color: white;
  border-color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(49,130,206,0.25);
}
.tech-item:hover i { color: white; }
.tech-item i {
  color: var(--accent-primary);
  font-size: 0.85rem;
  transition: color 0.2s ease;
}

/* Feature list */
.feature-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.feature-list li {
  padding: 0.5rem 0;
  padding-left: 1.6rem;
  position: relative;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  border-bottom: 1px solid #f8f9fa;
  line-height: 1.5;
}
.feature-list li:last-child { border-bottom: none; }
.feature-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-gradient);
}

/* External links */
.external-links a {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.65rem 0.85rem;
  background: #f8fafc;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 600;
  font-size: var(--font-size-sm);
  margin-bottom: 0.5rem;
  transition: all 0.25s var(--ease-out-quart);
}
.external-links a:last-child { margin-bottom: 0; }
.external-links a:hover {
  background: white;
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  transform: translateX(4px);
  box-shadow: 0 6px 16px rgba(49,130,206,0.15);
}
.external-links a i {
  font-size: 1rem;
  width: 18px;
  text-align: center;
}

/* ---- Image Modal ---- */
.image-modal {
  position: fixed;
  inset: 0;
  z-index: 9999;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}
.image-modal.active { opacity: 1; visibility: visible; }
.image-modal .modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.92);
  backdrop-filter: blur(6px);
}
.image-modal .modal-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.95);
  max-width: 90vw;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s ease;
}
.image-modal.active .modal-content { transform: translate(-50%, -50%) scale(1); }
.image-modal .modal-close {
  position: fixed;
  top: 1.25rem;
  right: 1.25rem;
  width: 44px;
  height: 44px;
  border: none;
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  transition: all 0.25s ease;
  font-size: 1.1rem;
}
.image-modal .modal-close:hover {
  background: rgba(255, 255, 255, 0.25);
  transform: rotate(90deg);
}
.image-modal img {
  max-width: 100%;
  max-height: 80vh;
  border-radius: var(--border-radius);
  display: block;
  margin: 0 auto;
}
.modal-caption {
  text-align: center;
  color: rgba(255, 255, 255, 0.8);
  margin-top: 0.75rem;
  font-size: var(--font-size-sm);
}

.content-text img {
  max-width: 100%;
  height: auto;
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: 0 6px 18px var(--shadow-soft);
}

/* ---- Table of Contents (auto-generated) ---- */
.table-of-contents {
  display: none; /* TOC now lives in the sticky sidebar instead */
}
.sidebar-card.toc-card .toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.sidebar-card.toc-card .toc-list li { margin: 0; }
.sidebar-card.toc-card .toc-list a {
  display: block;
  padding: 0.4rem 0.6rem;
  border-radius: 6px;
  text-decoration: none;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  transition: all 0.2s ease;
  border-left: 2px solid transparent;
}
.sidebar-card.toc-card .toc-list a.h3 {
  padding-left: 1.4rem;
  font-size: 0.8rem;
}
.sidebar-card.toc-card .toc-list a:hover {
  background: rgba(49,130,206,0.06);
  color: var(--accent-primary);
  border-left-color: var(--accent-primary);
}
.sidebar-card.toc-card .toc-list a.active {
  background: rgba(49,130,206,0.08);
  color: var(--accent-primary-dark);
  border-left-color: var(--accent-primary);
  font-weight: 600;
}

/* ---- Responsive ---- */
@media (max-width: 1024px) {
  .content-grid {
    grid-template-columns: 1fr 280px;
    gap: 2rem;
  }
  .project-header .project-title { font-size: 2.4rem; }
}

@media (max-width: 768px) {
  .back-nav {
    top: 1rem;
    left: 1rem;
    padding: 8px 14px;
    font-size: 0.85rem;
  }
  .project-header {
    padding: 5rem 0 2rem;
  }
  .project-header .project-title { font-size: 1.85rem; }
  .project-header .project-subtitle { font-size: var(--font-size-base); }
  .project-content { padding: 2rem 0 3rem; }
  .content-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 0 var(--spacing-sm);
  }
  .sidebar {
    position: static; /* no sticky on mobile */
  }
  .main-content { padding: 1.5rem; }
  .image-gallery { grid-template-columns: 1fr; }
  .image-modal .modal-content { max-width: 96vw; max-height: 96vh; }
  .image-modal img { max-height: 85vh; min-width: 280px; object-fit: contain; }
  .image-modal .modal-close {
    top: 0.75rem;
    right: 0.75rem;
    width: 38px;
    height: 38px;
  }
}

@media (max-width: 480px) {
  .project-header { padding: 4.5rem 0 1.5rem; }
  .project-header .project-title { font-size: 1.55rem; }
  .main-content { padding: 1.25rem; }
  .sidebar-card { padding: 1.25rem; }
  .content-section h2 { font-size: var(--font-size-lg); }
}