:root {
  color-scheme: light dark;
  --bg-primary: #0f1115;
  --bg-secondary: #151821;
  --bg-card: #1a1d26;
  --bg-card-hover: #1f2330;
  --border-color: #2a2d38;
  --border-active: #56ccf2;
  --text-primary: #f2f4f8;
  --text-secondary: #a5adbb;
  --text-muted: #6b7280;
  --accent: #56ccf2;
  --accent-hover: #7dd8f5;
  --link: #7ab8ff;
  --shadow: rgba(0, 0, 0, 0.3);
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
}

header {
  padding: 28px 32px 20px;
  border-bottom: 1px solid var(--border-color);
  background: linear-gradient(180deg, #181b22 0%, var(--bg-primary) 100%);
}

.header-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 8px;
}

header h1 {
  margin: 0;
  font-size: 24px;
  font-weight: 700;
  background: linear-gradient(90deg, var(--accent), #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

header p {
  margin: 0;
  font-size: 14px;
  color: var(--text-secondary);
}

.related-toggle {
  display: none;
  align-items: center;
  gap: 6px;
  background: var(--accent);
  color: #0f1115;
  border: none;
  border-radius: 999px;
  padding: 8px 14px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.2s ease;
}

.related-toggle:hover {
  background: var(--accent-hover);
}

.related-toggle:active {
  transform: scale(0.98);
}

main {
  display: grid;
  grid-template-columns: minmax(0, 1fr) clamp(280px, 32vw, 420px);
  gap: 24px;
  padding: 24px 32px 40px;
  max-width: 1600px;
  margin: 0 auto;
}

section {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 20px 24px;
  min-width: 0;
}

.related-panel {
  position: sticky;
  top: 24px;
  align-self: start;
  max-height: calc(100vh - 48px);
  display: flex;
  flex-direction: column;
  z-index: 40;
}

.related-panel #related-content {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding-right: 6px;
  margin-right: -6px;
}

.player-modal {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(10, 11, 13, 0.72);
  z-index: 80;
}

.player-modal.is-open {
  display: flex;
}

body.player-open {
  overflow: hidden;
}

.player-modal-content {
  width: min(92vw, 960px);
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
}

.player-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-color);
  flex-wrap: wrap;
}

.player-modal-title {
  font-size: 14px;
  font-weight: 600;
}

.player-modal-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.player-modal-nav {
  border: 1px solid var(--border-color);
  background: transparent;
  color: var(--text-primary);
  border-radius: 8px;
  padding: 6px 10px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, opacity 0.2s ease;
}

.player-modal-nav:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.player-modal-nav:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.player-modal-nav:disabled:hover {
  border-color: var(--border-color);
  color: var(--text-primary);
}

.player-modal-close {
  border: 1px solid var(--border-color);
  background: transparent;
  color: var(--text-primary);
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.player-modal-close:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.player-modal-body {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px;
}

.player-shell {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #0a0b0d;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border-color);
}

#player,
#player iframe {
  width: 100%;
  height: 100%;
}

.player-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 16px;
  text-align: center;
  color: var(--text-muted);
  background: linear-gradient(135deg, #1a1d26, #252833);
}

.player-placeholder-icon {
  font-size: 36px;
}

.player-placeholder-note {
  font-size: 11px;
  color: var(--text-secondary);
}

.player-status {
  font-size: 12px;
  color: var(--text-secondary);
  display: none;
}

.player-status.is-visible {
  display: block;
}

h2 {
  margin: 0 0 16px;
  font-size: 18px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
}

h2::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 20px;
  background: var(--accent);
  border-radius: 2px;
}

.related-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.related-panel-header h2 {
  margin: 0;
}

.drawer-close {
  display: none;
  border: 1px solid var(--border-color);
  background: transparent;
  color: var(--text-primary);
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.drawer-close:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 11, 13, 0.6);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
  z-index: 45;
}

body.drawer-open {
  overflow: hidden;
}

body.drawer-open .drawer-backdrop {
  opacity: 1;
  pointer-events: auto;
}

.filter-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  align-items: end;
  margin-bottom: 16px;
  padding: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.filter-label {
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.filter-input {
  background: var(--bg-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 13px;
}

.filter-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(86, 204, 242, 0.15);
}

.filter-range {
  display: flex;
  align-items: center;
  gap: 6px;
}

.filter-range-sep {
  font-size: 12px;
  color: var(--text-muted);
}

.sort-control {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.sort-toggle {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 2px;
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 999px;
}

.sort-button {
  background: transparent;
  color: var(--text-secondary);
  border: none;
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.sort-button:hover {
  color: var(--accent);
}

.sort-button.is-active {
  background: var(--accent);
  color: #0f1115;
}

.sort-button.is-active:hover {
  background: var(--accent-hover);
  color: #0f1115;
}

.sort-button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.sort-select {
  display: none;
  min-width: 160px;
}

.filter-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  flex-wrap: wrap;
  grid-column: 1 / -1;
}

.filter-action-buttons {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.filter-clear {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
}

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

.filter-toggle {
  background: var(--bg-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
}

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

.filter-count {
  font-size: 12px;
  color: var(--text-secondary);
}

.timeline-empty {
  grid-column: 1 / -1;
  text-align: center;
  padding: 32px 16px;
  color: var(--text-muted);
  font-size: 14px;
  background: var(--bg-card);
  border: 1px dashed var(--border-color);
  border-radius: 12px;
}

.timeline-group-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  min-height: 0;
}

.timeline-group {
  border: 1px solid var(--border-color);
  border-radius: 12px;
  background: var(--bg-secondary);
  overflow: hidden;
}

.timeline-group-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  background: var(--bg-card);
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.timeline-group-summary::marker,
.timeline-group-summary::-webkit-details-marker {
  color: var(--text-muted);
}

.timeline-group[open] .timeline-group-summary {
  border-bottom: 1px solid var(--border-color);
}

.timeline-group-count {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-secondary);
}

.timeline-group-content {
  padding: 16px;
}

.timeline-subgroup-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.timeline-subgroup {
  border-color: rgba(122, 184, 255, 0.25);
  background: rgba(15, 17, 21, 0.6);
}

.timeline-subgroup-summary {
  font-size: 13px;
  padding: 10px 14px;
  background: transparent;
}

.timeline-subgroup-content {
  padding: 12px;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.video-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
  cursor: pointer;
  transition: all 0.25s ease;
  position: relative;
}

.video-card:hover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--shadow);
}

.video-card.is-active {
  border-color: var(--border-active);
  background: rgba(86, 204, 242, 0.08);
  box-shadow: 0 0 0 3px rgba(86, 204, 242, 0.15);
}

.video-card.is-active::after {
  content: "選択中";
  position: absolute;
  top: 12px;
  right: 12px;
  background: var(--accent);
  color: #0f1115;
  font-size: 11px;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: 4px;
  z-index: 2;
}

.thumbnail-wrapper {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #0a0b0d;
  overflow: hidden;
}

.thumbnail {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.video-card:hover .thumbnail {
  transform: scale(1.05);
}

.thumbnail-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #1a1d26, #252833);
  color: var(--text-muted);
  font-size: 48px;
}

.play-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.4);
  opacity: 0;
  transition: opacity 0.25s ease;
}

.video-card:hover .play-overlay {
  opacity: 1;
}

.play-icon {
  width: 56px;
  height: 56px;
  background: var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(86, 204, 242, 0.4);
  transition: transform 0.2s ease;
}

.video-card:hover .play-icon {
  transform: scale(1.1);
}

.play-icon svg {
  width: 24px;
  height: 24px;
  fill: #0f1115;
  margin-left: 3px;
}

.video-info {
  padding: 14px 16px;
}

.video-title {
  font-size: 14px;
  font-weight: 500;
  line-height: 1.5;
  margin-bottom: 8px;
  display: -webkit-box;
  line-clamp: 2;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-meta {
  font-size: 12px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
}

.video-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.related-header {
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
}

.related-title {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
  line-height: 1.4;
}

.related-meta {
  font-size: 13px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.related-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 12px;
  background: var(--accent);
  color: #0f1115;
  font-size: 12px;
  font-weight: 600;
  border-radius: 6px;
  text-decoration: none;
  transition: background 0.2s ease;
  margin-top: 8px;
}

.related-link:hover {
  background: var(--accent-hover);
  text-decoration: none;
}

.related-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.related-item {
  display: flex;
  gap: 12px;
  padding: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  transition: all 0.2s ease;
  cursor: pointer;
  color: inherit;
  text-decoration: none;
}

button.related-item {
  width: 100%;
  font: inherit;
  text-align: left;
}

button.related-item:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.related-item:hover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
}

.related-thumb {
  width: 120px;
  min-width: 120px;
  aspect-ratio: 16 / 9;
  border-radius: 6px;
  overflow: hidden;
  background: #0a0b0d;
}

.related-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.related-info {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
}

.related-info .video-title {
  font-size: 13px;
  margin-bottom: 6px;
}

.related-info .video-meta {
  font-size: 11px;
}

.related-empty {
  text-align: center;
  padding: 32px 16px;
  color: var(--text-muted);
  font-size: 14px;
}

.related-empty-icon {
  font-size: 40px;
  margin-bottom: 12px;
  opacity: 0.5;
}

a {
  color: var(--link);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.error {
  color: #ff8c8c;
  font-size: 13px;
  padding: 16px;
  background: rgba(255, 140, 140, 0.1);
  border-radius: 8px;
  border: 1px solid rgba(255, 140, 140, 0.2);
}

.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px;
  color: var(--text-muted);
}

.loading-spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-right: 12px;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@media (max-width: 1100px) {
  main {
    grid-template-columns: 1fr;
  }

  .video-grid {
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  }

  .related-panel {
    position: static;
    max-height: none;
  }

  .related-panel #related-content {
    overflow: visible;
    padding-right: 0;
    margin-right: 0;
  }
}

@media (min-width: 1600px) {
  .filter-bar {
    grid-template-columns:
      minmax(220px, 1.2fr) minmax(240px, 1fr) minmax(160px, 0.6fr) minmax(180px, 0.6fr) minmax(220px, 0.8fr) auto;
  }

  .filter-actions {
    flex-direction: column;
    align-items: flex-end;
    justify-content: flex-start;
    grid-column: auto;
  }
}

@media (max-width: 900px) {
  .related-toggle {
    display: inline-flex;
  }

  .filter-bar {
    grid-template-columns: 1fr 1fr;
  }

  .filter-actions {
    align-items: flex-start;
  }

  .related-panel {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(92vw, 420px);
    max-height: none;
    transform: translateX(100%);
    transition: transform 0.25s ease;
    border-radius: 16px 0 0 16px;
    z-index: 60;
    display: block;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: calc(24px + env(safe-area-inset-bottom));
  }

  body.drawer-open .related-panel {
    transform: translateX(0);
    box-shadow: -16px 0 32px rgba(0, 0, 0, 0.4);
  }

  .related-panel #related-content {
    overflow: visible;
    min-height: auto;
    padding-right: 0;
    margin-right: 0;
  }

  .drawer-close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .related-panel-header {
    margin-bottom: 12px;
  }
}

@media (max-width: 600px) {
  header {
    padding: 20px 16px 16px;
  }

  header h1 {
    font-size: 20px;
  }

  main {
    padding: 16px;
    gap: 16px;
  }

  section {
    padding: 16px;
    border-radius: 12px;
  }

  .video-grid {
    grid-template-columns: 1fr;
  }

  .timeline-group-content {
    padding: 12px;
  }

  .filter-bar {
    grid-template-columns: 1fr;
  }

  .filter-input {
    font-size: 16px;
  }

  .filter-range {
    flex-wrap: wrap;
  }

  .sort-toggle {
    display: none;
  }

  .sort-select {
    display: block;
    width: 100%;
  }

  .related-thumb {
    width: 100px;
    min-width: 100px;
  }

  .player-modal {
    padding: 12px;
  }

  .player-modal-content {
    width: 100%;
    border-radius: 12px;
  }

  .player-modal-body {
    padding: 12px;
  }
}