* { box-sizing: border-box; }
html, body, #app { height: 100%; margin: 0; width: 100%; overflow-x: hidden; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
    'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  background: #fafafa;
  color: #222;
  font-size: 14px;
}
.app { max-width: 100vw; overflow-x: hidden; }

button { font: inherit; cursor: pointer; }
textarea, input { font: inherit; }

/* ====== layout ====== */

.app {
  display: grid;
  grid-template-columns: 260px 1fr;
  height: 100vh;
}

.sidebar {
  border-right: 1px solid #e5e5e5;
  background: #fff;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.sidebar-header {
  padding: 14px 16px;
  border-bottom: 1px solid #eee;
  display: flex;
  align-items: center;
  gap: 8px;
}
.sidebar-header h1 { margin: 0; font-size: 16px; font-weight: 600; }
.sidebar-header .new-btn {
  margin-left: auto;
  border: 1px solid #ddd;
  background: #fff;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 13px;
}
.sidebar-header .new-btn:hover { background: #f5f5f5; }

.doc-list { flex: 1; overflow-y: auto; padding: 6px; }
.doc-item {
  padding: 8px 10px;
  border-radius: 6px;
  cursor: pointer;
  margin-bottom: 2px;
  font-size: 13px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.doc-item:hover { background: #f3f3f3; }
.doc-item.active { background: #e8efff; }
.doc-item .title {
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.doc-item .meta { font-size: 11px; color: #888; }
.doc-item .del {
  border: none;
  background: transparent;
  color: #c44;
  font-size: 12px;
  visibility: hidden;
}
.doc-item:hover .del { visibility: visible; }

/* ====== workspace ====== */

.workspace {
  display: grid;
  grid-template-rows: 1fr auto;
  min-width: 0;
  min-height: 0;
  background: #fafafa;
  overflow: hidden;
}

.editor-pane > * { min-width: 0; min-height: 0; }
.workspace > * { min-width: 0; }
.input-bar { min-width: 0; box-sizing: border-box; overflow: hidden; }

.editor-pane {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: 0;
  border-bottom: 1px solid #e5e5e5;
}

.title-row {
  grid-column: 1 / -1;
  padding: 10px 16px;
  border-bottom: 1px solid #eee;
  background: #fff;
}
.title-row input {
  width: 100%;
  border: none;
  outline: none;
  font-size: 16px;
  font-weight: 600;
  background: transparent;
}

.editor, .preview {
  min-height: 0;
  overflow-y: auto;
  padding: 16px;
}
.editor {
  border-right: 1px solid #e5e5e5;
  background: #fff;
}
.editor { overflow-x: hidden; }
.editor textarea {
  width: 100%;
  max-width: 100%;
  height: 100%;
  border: none;
  outline: none;
  resize: none;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 13px;
  line-height: 1.6;
  background: transparent;
  word-break: break-all;
}
.preview {
  background: #fff;
  line-height: 1.6;
  overflow-x: hidden;
  word-wrap: break-word;
  overflow-wrap: anywhere;
}
.preview h1, .preview h2, .preview h3 { margin: 18px 0 8px; }
.preview p { margin: 8px 0; }
.preview pre {
  background: #f5f5f5; padding: 10px; border-radius: 6px;
  font-size: 12px; overflow-x: auto;
  max-width: 100%;
}
.preview code { background: #f5f5f5; padding: 1px 4px; border-radius: 3px; font-size: 12px; }
.preview pre code { background: transparent; padding: 0; word-wrap: normal; overflow-wrap: normal; }
.preview blockquote { border-left: 3px solid #ddd; margin: 8px 0; padding: 4px 12px; color: #555; }
.preview img { max-width: 100%; height: auto; }
.preview table { display: block; max-width: 100%; overflow-x: auto; }

/* ====== input bar ====== */

.input-bar {
  background: #fff;
  border-top: 1px solid #e5e5e5;
  padding: 10px 12px;
}
.input-row { display: flex; gap: 8px; align-items: flex-end; min-width: 0; }
.input-row textarea {
  flex: 1 1 0;
  min-width: 0;
  min-height: 40px;
  max-height: 160px;
  resize: none;
  padding: 9px 12px;
  border: 1px solid #ddd;
  border-radius: 8px;
  outline: none;
  font-size: 14px;
  line-height: 1.4;
}
.input-row textarea:focus { border-color: #6b7cff; }

.btn {
  height: 40px;
  padding: 0 14px;
  border-radius: 8px;
  border: 1px solid #ddd;
  background: #fff;
  font-size: 14px;
}
.btn:hover { background: #f5f5f5; }
.btn.primary { background: #5566ee; border-color: #4455dd; color: #fff; }
.btn.primary:hover { background: #4455dd; }
.btn.primary:disabled { background: #aaa; border-color: #aaa; cursor: not-allowed; }
.btn.mic { width: 44px; padding: 0; }
.btn.mic.on { background: #ee5566; border-color: #dd4455; color: #fff; }

.status {
  font-size: 12px;
  color: #666;
  padding: 4px 4px 0;
  min-height: 18px;
}
.status.err { color: #c44; }

/* ====== mobile-only chrome ====== */

.mobile-bar {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  background: #fff;
  border-bottom: 1px solid #e5e5e5;
  padding-top: max(8px, env(safe-area-inset-top));
}
.mobile-bar .hamburger,
.mobile-bar .pane-tabs button {
  border: 1px solid #ddd;
  background: #fff;
  border-radius: 6px;
  font-size: 14px;
  padding: 6px 10px;
}
.mobile-bar .pane-tabs {
  margin-left: auto;
  display: flex;
  gap: 4px;
}
.mobile-bar .pane-tabs button.active {
  background: #5566ee;
  color: #fff;
  border-color: #4455dd;
}
.mobile-bar .doc-title {
  flex: 1 1 0;
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-weight: 600;
  font-size: 14px;
}
.mobile-bar .doc-title input { min-width: 0; }

.sidebar-backdrop {
  display: none;
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.35);
  z-index: 50;
}

/* ====== mobile layout ====== */

@media (max-width: 768px) {
  .app {
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr;
    height: 100dvh;
  }

  .mobile-bar { display: flex; }

  /* sidebar becomes a slide-in drawer */
  .sidebar {
    position: fixed;
    top: 0; left: 0; bottom: 0;
    width: 78vw;
    max-width: 320px;
    border-right: 1px solid #e5e5e5;
    border-bottom: none;
    transform: translateX(-100%);
    transition: transform 0.2s ease;
    z-index: 60;
    box-shadow: 2px 0 8px rgba(0,0,0,0.1);
  }
  .app.drawer-open .sidebar { transform: translateX(0); }
  .app.drawer-open .sidebar-backdrop { display: block; }

  /* workspace fills the screen; editor + preview overlay each other,
     pane-tabs picks which one shows */
  .editor-pane {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr;
    position: relative;
  }
  .title-row { display: none; }  /* title shows in the mobile-bar instead */

  .editor, .preview {
    grid-column: 1;
    grid-row: 1;
    border-right: none;
    border-bottom: none;
    padding: 12px;
  }
  .editor { display: none; }
  .preview { display: none; }
  .app.pane-editor .editor { display: block; }
  .app.pane-preview .preview { display: block; }

  /* input bar honors safe area at bottom */
  .input-bar {
    padding-bottom: max(10px, env(safe-area-inset-bottom));
  }
  .input-row textarea {
    font-size: 16px;  /* iOS won't zoom in if >= 16px */
  }
  .btn { height: 44px; }  /* easier thumb target */
  .btn.mic { width: 48px; }
}

/* ====== modal ====== */

.modal-backdrop {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.4);
  display: flex; align-items: center; justify-content: center;
  z-index: 100;
}
.modal {
  background: #fff; padding: 20px; border-radius: 10px;
  width: 360px; max-width: 90vw;
}
.modal h2 { margin: 0 0 12px; font-size: 16px; }
.modal input {
  width: 100%; padding: 8px 10px; border: 1px solid #ddd; border-radius: 6px;
  margin-bottom: 12px; outline: none;
}
.modal-actions { display: flex; gap: 8px; justify-content: flex-end; }