:root {
  color-scheme: dark;
  --background: #0d0f12;
  --surface: #15191e;
  --surface-strong: #1c2229;
  --line: #2a313a;
  --line-strong: #3a444f;
  --text: #f3f5f7;
  --muted: #929ca8;
  --accent: #ff654c;
  --accent-hover: #ff7963;
  --danger: #ff7b74;
  --success: #71d99a;
  --radius: 16px;
  --shadow: 0 18px 60px rgb(0 0 0 / 0.24);
  font-family:
    Inter, "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  background: var(--background);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 85% 0%, rgb(255 101 76 / 0.09), transparent 28rem),
    var(--background);
}

button,
input,
select {
  font: inherit;
}

button {
  color: inherit;
}

button:focus-visible,
input:focus-visible,
select:focus-visible,
.drop-zone:focus-within {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.site-header,
.app-shell,
.site-footer {
  width: min(1440px, calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  padding: 40px 0 28px;
}

.eyebrow,
.step-label {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.16em;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 8px;
  font-size: clamp(1.7rem, 3vw, 2.7rem);
  line-height: 1.05;
  letter-spacing: -0.04em;
}

h2 {
  margin-bottom: 0;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
}

.subtitle {
  max-width: 760px;
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.7;
}

.privacy-badge {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: #c8d0d9;
  background: rgb(21 25 30 / 0.8);
  font-size: 0.78rem;
}

.privacy-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 4px rgb(113 217 154 / 0.12);
}

.app-shell {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(320px, 0.65fr);
  gap: 20px;
}

.workspace-card {
  min-width: 0;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgb(21 25 30 / 0.94);
  box-shadow: var(--shadow);
}

.source-panel,
.frames-panel {
  grid-column: 1;
}

.settings-panel,
.preview-panel {
  grid-column: 2;
}

.settings-panel {
  grid-row: 1;
  align-self: start;
}

.preview-panel {
  grid-row: 2 / span 2;
  align-self: start;
  position: sticky;
  top: 20px;
}

.section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.button,
.icon-button {
  border: 0;
  border-radius: 10px;
  cursor: pointer;
  transition:
    transform 150ms ease,
    background-color 150ms ease,
    opacity 150ms ease;
}

.button:hover:not(:disabled),
.icon-button:hover:not(:disabled) {
  transform: translateY(-1px);
}

.button:disabled,
.icon-button:disabled {
  cursor: not-allowed;
  opacity: 0.42;
}

.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 10px 16px;
  font-weight: 750;
}

.button-primary {
  color: #111;
  background: var(--accent);
}

.button-primary:hover:not(:disabled) {
  background: var(--accent-hover);
}

.button-ghost {
  min-height: 36px;
  padding: 7px 10px;
  border: 1px solid var(--line);
  color: var(--muted);
  background: transparent;
  font-size: 0.78rem;
}

.button-danger-text {
  width: 100%;
  margin-top: 14px;
  color: var(--danger);
  background: transparent;
  font-size: 0.82rem;
}

.drop-zone {
  display: grid;
  min-height: 240px;
  place-items: center;
  align-content: center;
  gap: 8px;
  padding: 28px;
  border: 1px dashed var(--line-strong);
  border-radius: 13px;
  color: var(--muted);
  text-align: center;
  background: #11151a;
  cursor: pointer;
  transition:
    border-color 150ms ease,
    background-color 150ms ease;
}

.drop-zone:hover,
.drop-zone.is-dragging {
  border-color: var(--accent);
  background: rgb(255 101 76 / 0.05);
}

.drop-zone input {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
}

.drop-zone strong {
  color: var(--text);
  font-size: 1.05rem;
}

.drop-zone small {
  margin-top: 10px;
  font-size: 0.76rem;
}

.drop-icon {
  display: grid;
  width: 50px;
  height: 50px;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  color: var(--accent);
  font-size: 1.8rem;
}

.file-info {
  margin-bottom: 14px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--muted);
  font-size: 0.78rem;
  line-height: 1.6;
}

.file-info strong {
  color: var(--text);
}

.message {
  margin: 12px 0;
  padding: 12px 14px;
  border-radius: 10px;
  font-size: 0.84rem;
  line-height: 1.6;
}

.message-error {
  border: 1px solid rgb(255 123 116 / 0.28);
  color: #ffc1bd;
  background: rgb(255 123 116 / 0.08);
}

.video-frame {
  position: relative;
  display: grid;
  min-height: 240px;
  place-items: center;
  overflow: hidden;
  border-radius: 12px;
  background: #08090b;
}

.video-frame video {
  display: block;
  width: 100%;
  max-height: min(62vh, 720px);
  object-fit: contain;
}

.loading-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: rgb(8 9 11 / 0.76);
  font-size: 0.8rem;
}

.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgb(255 255 255 / 0.2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.transport-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 14px;
}

.icon-button {
  display: grid;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  place-items: center;
  border: 1px solid var(--line);
  background: var(--surface-strong);
}

.timeline-stack {
  min-width: 0;
  flex: 1;
}

.timeline-wrap {
  position: relative;
  height: 24px;
  display: flex;
  align-items: center;
}

.timeline {
  width: 100%;
  height: 5px;
  margin: 0;
  accent-color: var(--accent);
  cursor: pointer;
}

.capture-markers {
  position: absolute;
  inset: 0 8px;
  z-index: 2;
  pointer-events: none;
}

.capture-marker {
  position: absolute;
  top: 1px;
  width: 3px;
  height: 11px;
  border: 0;
  border-radius: 2px;
  background: #fff;
  transform: translateX(-50%);
  pointer-events: auto;
  cursor: pointer;
}

.time-row {
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  font-size: 0.74rem;
}

.capture-button {
  width: 100%;
  margin-top: 14px;
}

.frame-count,
.grid-summary {
  color: var(--muted);
  font-size: 0.8rem;
}

.frame-count strong {
  color: var(--text);
  font-size: 1rem;
}

.empty-state {
  display: grid;
  min-height: 160px;
  place-items: center;
  align-content: center;
  gap: 10px;
  padding: 24px;
  border: 1px dashed var(--line);
  border-radius: 12px;
  color: var(--muted);
  text-align: center;
}

.empty-state p {
  max-width: 380px;
  margin-bottom: 0;
  font-size: 0.83rem;
  line-height: 1.65;
}

.empty-icon {
  color: var(--line-strong);
  font-size: 2rem;
}

.frame-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 12px;
}

.frame-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: #101419;
}

.frame-seek {
  position: relative;
  display: block;
  width: 100%;
  padding: 0;
  overflow: hidden;
  border: 0;
  background: #090b0e;
  cursor: pointer;
}

.frame-seek img {
  display: block;
  width: 100%;
  aspect-ratio: var(--video-aspect, 16 / 9);
  object-fit: contain;
}

.frame-number {
  position: absolute;
  top: 8px;
  left: 8px;
  display: grid;
  min-width: 25px;
  height: 25px;
  place-items: center;
  padding: 0 6px;
  border-radius: 6px;
  background: rgb(0 0 0 / 0.72);
  color: #fff;
  font-size: 0.76rem;
  font-weight: 800;
}

.frame-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 9px 10px;
}

.frame-meta time {
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  font-size: 0.72rem;
}

.delete-frame {
  min-height: 30px;
  padding: 4px 8px;
  border: 0;
  border-radius: 7px;
  color: var(--danger);
  background: transparent;
  cursor: pointer;
  font-size: 0.72rem;
}

.delete-frame:hover {
  background: rgb(255 123 116 / 0.09);
}

.settings-grid {
  display: grid;
  gap: 14px;
}

.field,
.toggle-field {
  display: grid;
  gap: 8px;
}

.field > span,
.toggle-field strong {
  font-size: 0.82rem;
}

.field input,
.field select {
  width: 100%;
  min-height: 44px;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 9px;
  color: var(--text);
  background: #101419;
}

.toggle-field {
  grid-template-columns: 1fr auto;
  align-items: center;
  padding: 12px 0 0;
  border-top: 1px solid var(--line);
}

.toggle-field span {
  display: grid;
  gap: 3px;
}

.toggle-field small {
  color: var(--muted);
  font-size: 0.72rem;
}

.toggle-field input {
  width: 42px;
  height: 24px;
  accent-color: var(--accent);
  cursor: pointer;
}

.preview-viewport {
  overflow: auto;
  max-height: 64vh;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background:
    linear-gradient(45deg, #101318 25%, transparent 25%),
    linear-gradient(-45deg, #101318 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #101318 75%),
    linear-gradient(-45deg, transparent 75%, #101318 75%),
    #0d1014;
  background-position:
    0 0,
    0 8px,
    8px -8px,
    -8px 0;
  background-size: 16px 16px;
}

.preview-viewport canvas {
  display: block;
  width: 100%;
  height: auto;
  margin: auto;
  box-shadow: 0 8px 30px rgb(0 0 0 / 0.4);
}

.export-button {
  width: 100%;
  margin-top: 16px;
}

.status-message {
  min-height: 1.4em;
  margin: 10px 0 0;
  color: var(--muted);
  text-align: center;
  font-size: 0.76rem;
}

.site-footer {
  padding: 26px 0 42px;
  color: var(--muted);
  text-align: center;
  font-size: 0.75rem;
}

.site-footer p {
  margin-bottom: 0;
}

[hidden] {
  display: none !important;
}

@media (max-width: 960px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .source-panel,
  .frames-panel,
  .settings-panel,
  .preview-panel {
    grid-column: 1;
    grid-row: auto;
  }

  .preview-panel {
    position: static;
  }
}

@media (max-width: 640px) {
  .site-header,
  .app-shell,
  .site-footer {
    width: min(100% - 24px, 1440px);
  }

  .site-header {
    display: block;
    padding-top: 28px;
  }

  .privacy-badge {
    margin-top: 18px;
  }

  .workspace-card {
    padding: 17px;
    border-radius: 14px;
  }

  .section-heading {
    align-items: flex-start;
  }

  .drop-zone {
    min-height: 210px;
  }

  .video-frame {
    min-height: 180px;
  }

  .frame-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 380px) {
  .frame-grid {
    grid-template-columns: 1fr;
  }
}