:root {
  --color-bg: #faf8f5;
  --color-surface: #ffffff;
  --color-text: #2a2a2a;
  --color-text-soft: #6b6b6b;
  --color-line: #e8e3dc;
  --color-accent: #1a1a1a;
  --color-accent-soft: #4a4a4a;
  --color-success: #2c8a5e;
  --color-warning: #c47a00;
  --color-error: #c43a3a;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --font-jp: "Hiragino Sans", "Yu Gothic", "Meiryo", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-jp);
  font-size: 16px;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

button {
  font-family: inherit;
  cursor: pointer;
}

/* ===== Header ===== */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 8px;
}
.brand-mark {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: 0.05em;
}
.brand-divider {
  color: var(--color-text-soft);
}
.brand-tool {
  font-size: 14px;
  color: var(--color-text-soft);
  letter-spacing: 0.04em;
}
.header-meta {
  font-size: 13px;
  color: var(--color-text-soft);
}

/* ===== Step Nav ===== */
.step-nav {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
  padding: 12px 16px;
  overflow-x: auto;
}
.step-nav ol {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
  min-width: max-content;
}
.step {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-soft);
  white-space: nowrap;
}
.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-line);
  color: var(--color-text-soft);
  font-weight: 600;
  font-size: 13px;
}
.step.is-active {
  color: var(--color-accent);
  font-weight: 600;
}
.step.is-active .step-num {
  background: var(--color-accent);
  color: #fff;
}
.step.is-done .step-num {
  background: var(--color-success);
  color: #fff;
}

/* ===== Main ===== */
.app-main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px 20px 80px;
}
.step-panel {
  display: none;
}
.step-panel.is-active {
  display: block;
}
.panel-title {
  font-size: 22px;
  font-weight: 600;
  margin: 0 0 8px;
}
.panel-hint {
  color: var(--color-text-soft);
  margin: 0 0 24px;
}

/* ===== Dropzone ===== */
.dropzone {
  border: 2px dashed var(--color-line);
  border-radius: var(--radius-lg);
  padding: 48px 24px;
  text-align: center;
  background: var(--color-surface);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
  color: var(--color-text-soft);
}
.dropzone:hover, .dropzone:focus-visible, .dropzone.is-dragover {
  border-color: var(--color-accent);
  background: #fff;
  color: var(--color-accent);
  outline: none;
}
.dropzone-icon {
  display: flex;
  justify-content: center;
  margin-bottom: 12px;
}
.dropzone-main {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 4px;
}
.dropzone-sub {
  font-size: 14px;
}

/* ===== Video Meta ===== */
.video-meta {
  margin-top: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px 20px;
}
.meta-row {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  border-bottom: 1px solid var(--color-line);
  font-size: 14px;
}
.meta-row:last-child {
  border-bottom: none;
}
.meta-key {
  color: var(--color-text-soft);
}
.meta-val {
  font-weight: 500;
}

/* ===== Buttons ===== */
.step-actions {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 32px;
}
.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  padding: 14px 24px;
  font-size: 15px;
  font-weight: 600;
  min-height: 48px;
}
.btn-primary:disabled {
  background: var(--color-line);
  color: var(--color-text-soft);
  cursor: not-allowed;
}
.btn-primary:not(:disabled):hover {
  background: var(--color-accent-soft);
}
.btn-back {
  background: transparent;
  color: var(--color-text-soft);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 14px 24px;
  font-size: 15px;
  min-height: 48px;
}
.btn-back:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.btn-secondary {
  background: var(--color-surface);
  color: var(--color-accent);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  padding: 8px 16px;
  font-size: 13px;
}
.btn-secondary:hover {
  border-color: var(--color-accent);
}
.btn-mini {
  background: var(--color-line);
  color: var(--color-text);
  border: none;
  border-radius: var(--radius-sm);
  padding: 4px 10px;
  font-size: 12px;
  margin-right: 8px;
}
.btn-mini:hover {
  background: var(--color-accent);
  color: #fff;
}
.btn-icon {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  font-size: 14px;
}
.btn-generate {
  background: var(--color-accent);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  padding: 18px 36px;
  font-size: 17px;
  font-weight: 600;
  min-height: 56px;
  width: 100%;
  max-width: 300px;
  display: block;
  margin: 0 auto;
}

/* ===== Editor (Step 2) ===== */
.editor-layout {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 24px;
}
@media (max-width: 768px) {
  .editor-layout {
    grid-template-columns: 1fr;
  }
}
.preview-wrap {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px;
}
.preview-container {
  position: relative;
  width: 100%;
  max-width: 360px;
  aspect-ratio: 9/16;
  margin: 0 auto;
  background: #000;
  border-radius: var(--radius-sm);
  overflow: hidden;
}
.preview-container video {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
.region-canvas {
  position: absolute;
  inset: 0;
  cursor: crosshair;
  width: 100%;
  height: 100%;
}
.preview-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 12px;
}
.seek-bar {
  flex: 1;
}
.time-display {
  font-size: 13px;
  color: var(--color-text-soft);
  font-variant-numeric: tabular-nums;
  min-width: 90px;
  text-align: right;
}

/* Region Side Panel */
.region-side {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.region-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px;
}
.card-title {
  font-size: 14px;
  font-weight: 600;
  margin: 0 0 12px;
  color: var(--color-text);
}
.region-info {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 12px;
}
.region-row {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  padding: 4px 8px;
  background: var(--color-bg);
  border-radius: var(--radius-sm);
}
.region-key {
  color: var(--color-text-soft);
}
.region-val {
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}
.time-control label {
  display: block;
  font-size: 13px;
  margin-bottom: 8px;
}
.time-val {
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}

/* ===== Translation Grid (Step 3) ===== */
.translation-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 24px;
}
@media (max-width: 768px) {
  .translation-grid {
    grid-template-columns: 1fr;
  }
}
.trans-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  flex-direction: column;
}
.trans-label {
  font-size: 13px;
  color: var(--color-text-soft);
  margin-bottom: 8px;
  font-weight: 500;
}
.trans-input {
  width: 100%;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  font-size: 15px;
  font-family: inherit;
  resize: vertical;
}
.trans-input:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: -1px;
}

/* Style Card */
.style-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px;
}
.style-controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}
.style-controls label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  color: var(--color-text-soft);
}

/* ===== Generation (Step 4) ===== */
.generate-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  text-align: center;
}
.gen-status {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: left;
}
.gen-stage {
  display: grid;
  grid-template-columns: 100px 1fr 80px;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  background: var(--color-bg);
  border-radius: var(--radius-sm);
}
.gen-name {
  font-weight: 500;
}
.gen-state {
  font-size: 13px;
  color: var(--color-text-soft);
  text-align: right;
}
.gen-bar {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  overflow: hidden;
}

/* Result */
.result-area {
  margin-top: 32px;
}
.result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 12px;
}
.result-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
}
.result-lang {
  font-weight: 600;
  margin-bottom: 12px;
}
.result-video {
  width: 100%;
  aspect-ratio: 9/16;
  background: #000;
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
}
.btn-download {
  display: inline-block;
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 600;
}
.btn-download:hover {
  background: var(--color-accent-soft);
}

/* ===== Footer ===== */
.app-footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-line);
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--color-text-soft);
}

/* ===== Overlay ===== */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}
.overlay[hidden] {
  display: none;
}
.overlay-card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: 32px 48px;
  text-align: center;
  box-shadow: var(--shadow-md);
}
.overlay-spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--color-line);
  border-top-color: var(--color-accent);
  border-radius: 50%;
  margin: 0 auto 16px;
  animation: spin 1s linear infinite;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}
.overlay-message {
  font-size: 15px;
  color: var(--color-text);
}

/* ===== Responsive ===== */
@media (max-width: 600px) {
  .app-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }
  .header-meta {
    font-size: 12px;
  }
  .panel-title {
    font-size: 18px;
  }
  .step-actions {
    flex-direction: column-reverse;
  }
  .btn-primary, .btn-back {
    width: 100%;
  }
  .step-nav ol {
    gap: 12px;
    justify-content: flex-start;
  }
  .step-label {
    display: none;
  }
}