/* ============================================================
   Exam Paper Cutter — Main Stylesheet
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #f5f6fa;
  --surface: #ffffff;
  --border: #dde1ea;
  --primary: #4f6ef7;
  --primary-dark: #3a57d6;
  --danger: #e74c3c;
  --success: #27ae60;
  --warning: #f39c12;
  --text: #2c3e50;
  --text-muted: #7f8c8d;
  --cut-color: #e74c3c;
  --cut-hover: #c0392b;
  --radius: 10px;
  --shadow: 0 2px 12px rgba(0,0,0,.08);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

/* ---- Layout ---- */
.app-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}
.app-header h1 { font-size: 18px; font-weight: 700; }
.app-header .version { font-size: 12px; color: var(--text-muted); }

.app-body {
  display: flex;
  height: calc(100vh - 56px);
  overflow: hidden;
}

/* ---- Sidebar ---- */
.sidebar {
  width: 300px;
  min-width: 260px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  padding: 16px;
  gap: 16px;
}

.section-title {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

/* ---- Upload Area ---- */
.upload-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 28px 16px;
  text-align: center;
  cursor: pointer;
  transition: border-color .2s, background .2s;
}
.upload-zone:hover, .upload-zone.drag-over {
  border-color: var(--primary);
  background: #f0f4ff;
}
.upload-zone svg { color: var(--primary); margin-bottom: 8px; }
.upload-zone p { font-size: 14px; color: var(--text-muted); }
.upload-zone p strong { color: var(--text); }
#file-input { display: none; }

/* ---- Form Controls ---- */
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 13px; font-weight: 500; }
.form-group select,
.form-group input[type="number"] {
  height: 36px;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0 10px;
  font-size: 14px;
  background: var(--surface);
  color: var(--text);
  outline: none;
  transition: border-color .2s;
}
.form-group select:focus,
.form-group input[type="number"]:focus {
  border-color: var(--primary);
}

.toggle-group {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
}
.toggle-group button {
  flex: 1;
  padding: 7px;
  border: none;
  background: transparent;
  font-size: 13px;
  cursor: pointer;
  transition: background .15s, color .15s;
}
.toggle-group button.active {
  background: var(--primary);
  color: #fff;
  font-weight: 600;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 16px;
  border: none;
  border-radius: 7px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: opacity .15s, transform .1s;
}
.btn:active { transform: scale(.97); }
.btn:disabled { opacity: .45; cursor: not-allowed; }

.btn-primary   { background: var(--primary); color: #fff; }
.btn-primary:hover:not(:disabled)   { background: var(--primary-dark); }
.btn-danger    { background: var(--danger);  color: #fff; }
.btn-danger:hover:not(:disabled)    { background: #c0392b; }
.btn-success   { background: var(--success); color: #fff; }
.btn-success:hover:not(:disabled)   { background: #1e8449; }
.btn-warning   { background: var(--warning); color: #fff; }
.btn-warning:hover:not(:disabled)   { background: #d68910; }
.btn-ghost {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-ghost:hover:not(:disabled) { background: var(--bg); }
.btn-full { width: 100%; }

.action-buttons { display: flex; flex-direction: column; gap: 8px; }

/* ---- Toast ---- */
#toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 9999;
}
.toast {
  min-width: 240px;
  padding: 12px 16px;
  border-radius: 8px;
  color: #fff;
  font-size: 14px;
  box-shadow: 0 4px 16px rgba(0,0,0,.18);
  animation: slide-in .25s ease;
}
.toast.info    { background: var(--primary); }
.toast.success { background: var(--success); }
.toast.error   { background: var(--danger);  }
.toast.warning { background: var(--warning); }
@keyframes slide-in {
  from { opacity: 0; transform: translateX(40px); }
  to   { opacity: 1; transform: translateX(0); }
}

/* ---- Loading Overlay ---- */
.loading-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.35);
  z-index: 500;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  color: #fff;
  font-size: 16px;
}
.loading-overlay.active { display: flex; }
.spinner {
  width: 44px; height: 44px;
  border: 4px solid rgba(255,255,255,.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---- Main Content ---- */
.main-content {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  gap: 12px;
}
.empty-state svg { opacity: .3; }
.empty-state p { font-size: 16px; }

/* ---- Page Card ---- */
.page-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.page-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  background: #fafbfd;
}
.page-card-header h3 { font-size: 14px; font-weight: 600; }
.page-card-actions { display: flex; gap: 8px; }

.page-card-body { padding: 16px; }

/* ---- Double Column Layout ---- */
.columns-wrapper {
  display: flex;
  gap: 16px;
}
.column-panel {
  flex: 1;
  min-width: 0;
}
.column-panel h4 {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

/* ---- Image + Cut Lines Canvas ---- */
.canvas-wrapper {
  position: relative;
  display: block;
  width: 100%;
  user-select: none;
}
.canvas-wrapper img.page-img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 6px;
}

/* Cut-line overlay — 覆盖在图片上，高度由 JS 同步设置 */
.cut-overlay {
  position: absolute;
  top: 0; left: 0; right: 0;
  pointer-events: none;
  overflow: visible;
}

.cut-line {
  position: absolute;
  left: 0; right: 0;
  height: 0;
  pointer-events: all;
  cursor: ns-resize;
  z-index: 10;
}
/* 红色实线 + 虚线双重效果，更易看到 */
.cut-line-rule {
  position: absolute;
  left: 0; right: 0;
  top: -2px;
  height: 4px;
  background: repeating-linear-gradient(
    90deg,
    var(--cut-color) 0px,
    var(--cut-color) 10px,
    transparent 10px,
    transparent 16px
  );
  box-shadow: 0 0 0 1px rgba(231,76,60,.3);
  cursor: ns-resize;
  transition: filter .15s;
}
.cut-line:hover .cut-line-rule {
  filter: brightness(1.2);
  box-shadow: 0 0 0 2px rgba(231,76,60,.4);
}

.cut-line-label {
  position: absolute;
  left: 8px;
  top: 4px;
  background: var(--cut-color);
  color: #fff;
  font-size: 11px;
  font-weight: 600;
  padding: 2px 7px;
  border-radius: 4px;
  white-space: nowrap;
  cursor: text;
  pointer-events: all;
  box-shadow: 0 1px 4px rgba(0,0,0,.25);
}
.cut-line-label:focus {
  outline: 2px solid var(--primary);
  background: var(--primary);
}
.cut-line-label:empty::before {
  content: "点击编辑题号";
  opacity: .5;
}

.cut-line-delete {
  position: absolute;
  right: 8px;
  top: -12px;
  width: 22px; height: 22px;
  background: var(--cut-color);
  color: #fff;
  border: 2px solid #fff;
  border-radius: 50%;
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: all;
  box-shadow: 0 1px 4px rgba(0,0,0,.25);
}
.cut-line-delete:hover { background: var(--cut-hover); }

/* Add-line ghost that follows cursor */
.add-line-ghost {
  position: absolute;
  left: 0; right: 0;
  height: 2px;
  background: var(--primary);
  opacity: 0;
  pointer-events: none;
  transition: opacity .1s;
}
.canvas-wrapper.add-mode .add-line-ghost { opacity: .7; }
.canvas-wrapper.add-mode { cursor: crosshair; }

/* Section label between two cut lines */
.section-label {
  position: absolute;
  right: 30px;
  background: rgba(79,110,247,.12);
  color: var(--primary);
  font-size: 11px;
  padding: 1px 6px;
  border-radius: 4px;
  pointer-events: none;
}

/* ---- Split line indicator (double mode) ---- */
.split-line {
  position: absolute;
  top: 0; bottom: 0;
  width: 3px;
  background: var(--primary);
  opacity: .6;
  cursor: ew-resize;
  z-index: 10;
}
.split-line::after {
  content: "◀▶";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: var(--primary);
  color: #fff;
  font-size: 10px;
  padding: 2px 4px;
  border-radius: 3px;
  white-space: nowrap;
}

/* ---- Progress indicator ---- */
.progress-bar-wrap {
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  overflow: hidden;
  margin-top: 6px;
}
.progress-bar {
  height: 100%;
  background: var(--primary);
  transition: width .3s;
}

/* ---- Stats chip ---- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  background: #e8eeff;
  color: var(--primary);
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
}

/* ---- 引擎标记 ---- */
.engine-badge {
  display: inline-block;
  font-size: 10px;
  font-weight: 600;
  padding: 1px 6px;
  border-radius: 10px;
  margin-left: 6px;
  vertical-align: middle;
}
.engine-badge.aliyun {
  background: #fff3e0;
  color: #e65100;
  border: 1px solid #ffcc80;
}
.engine-badge.openrouter {
  background: #e8eeff;
  color: var(--primary);
  border: 1px solid #c5d0ff;
}

/* ---- 识别预览面板 ---- */
.preview-panel {
  border-top: 1px solid var(--border);
  padding: 16px;
  background: #f9fafc;
}
.preview-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
}
.preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}
.preview-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 1px 4px rgba(0,0,0,.06);
  transition: box-shadow .15s;
}
.preview-item:hover { box-shadow: 0 3px 10px rgba(0,0,0,.12); }
.preview-item img {
  display: block;
  width: 100%;
  height: auto;
}
.preview-img-wrap { line-height: 0; }
.preview-img-wrap .no-img-tip {
  padding: 20px;
  text-align: center;
  color: var(--text-muted);
  font-size: 12px;
  background: var(--bg);
}

.preview-item-info {
  border-top: 1px solid var(--border);
  background: #f5f6fa;
}
.preview-item-label {
  padding: 5px 8px;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
}
.preview-stem {
  padding: 2px 8px 6px;
  font-size: 11px;
  color: var(--text);
  line-height: 1.5;
  word-break: break-all;
}
.q-type-badge {
  display: inline-block;
  font-size: 10px;
  padding: 0 5px;
  background: #e8f5e9;
  color: #2e7d32;
  border-radius: 4px;
  font-weight: normal;
}

/* ---- Scrollbar ---- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #c8cdd6; border-radius: 3px; }

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .app-body { flex-direction: column; }
  .sidebar { width: 100%; height: auto; border-right: none; border-bottom: 1px solid var(--border); }
  .columns-wrapper { flex-direction: column; }
  .preview-grid { grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); }
}