:root {
  --bg: #0f172a;
  --panel: rgba(15, 23, 42, 0.8);
  --panel-2: #111827;
  --line: rgba(148, 163, 184, 0.18);
  --text: #e5eefc;
  --muted: #9fb0c9;
  --accent: #60a5fa;
  --accent-2: #22c55e;
  --danger: #f87171;
  --shadow: 0 20px 60px rgba(0, 0, 0, 0.28);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: linear-gradient(180deg, #020617, #0f172a 30%, #111827 100%);
  color: var(--text);
  min-height: 100vh;
}
button, input { font: inherit; }
button {
  border: 0;
  border-radius: 14px;
  padding: 10px 14px;
  cursor: pointer;
  color: white;
  background: #2563eb;
}
button.ghost {
  background: transparent;
  border: 1px solid var(--line);
}
button.danger { color: #fecaca; border-color: rgba(248, 113, 113, 0.35); }
button.danger-solid {
  background: #dc2626;
  color: #fff;
}
.app-shell {
  display: grid;
  grid-template-columns: 320px 1fr;
  min-height: 100vh;
}
.sidebar, .main-panel { backdrop-filter: blur(14px); }
.sidebar {
  border-right: 1px solid var(--line);
  padding: 18px;
  background: rgba(2, 6, 23, 0.65);
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand h1 { margin: 0; font-size: 24px; }
.brand p, .hint { margin: 4px 0 0; color: var(--muted); font-size: 13px; }
.mobile-toggle { display: none; background: rgba(96, 165, 250, 0.14); color: var(--text); }
.sidebar-actions button { width: 100%; }
.tab-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  overflow: auto;
}
.tab-item {
  width: 100%;
  text-align: left;
  background: rgba(15, 23, 42, 0.9);
  border: 1px solid transparent;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}
.tab-item.active {
  border-color: rgba(96, 165, 250, 0.5);
  background: rgba(37, 99, 235, 0.22);
}
.tab-title {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.tab-meta { color: var(--muted); font-size: 12px; }
.upload-panel {
  background: rgba(15, 23, 42, 0.75);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 14px;
}
.bottom-upload-panel {
  margin-top: 0;
}
.upload-panel h3, .uploads-wrap h3 { margin: 0 0 10px; }
.upload-button {
  display: block;
  width: 100%;
}
.upload-button input { display: none; }
.upload-button span {
  display: block;
  background: rgba(34, 197, 94, 0.16);
  border: 1px dashed rgba(34, 197, 94, 0.35);
  color: #dcfce7;
  text-align: center;
  padding: 12px;
  border-radius: 14px;
}
.main-panel {
  padding: 18px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 14px;
}
.topbar, .editor-wrap, .uploads-wrap {
  background: rgba(15, 23, 42, 0.78);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: var(--shadow);
}
.bottom-panels {
  display: grid;
  gap: 14px;
}
.topbar {
  display: flex;
  gap: 12px;
  align-items: center;
  padding: 14px;
}
.title-input {
  flex: 1;
  background: rgba(2, 6, 23, 0.6);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px 14px;
}
.file-search-input {
  width: 100%;
  background: rgba(2, 6, 23, 0.6);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px 14px;
  margin-bottom: 12px;
}
.status-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
}
.save-status {
  color: var(--muted);
  font-size: 14px;
  min-width: 84px;
  text-align: right;
}
.editor-wrap { padding: 16px; }
.editor {
  min-height: 52vh;
  outline: none;
  line-height: 1.65;
  font-size: 16px;
}
.editor img {
  max-width: 100%;
  border-radius: 12px;
  margin: 10px 0;
}
.editor:empty:before {
  content: '在这里写内容……也可以直接把截图或图片粘贴进来。';
  color: #6b7b95;
}
.uploads-wrap { padding: 16px; }
.section-title-row {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
  margin-bottom: 12px;
}
.uploads-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}
.upload-card {
  border: 1px solid var(--line);
  background: rgba(2, 6, 23, 0.55);
  border-radius: 16px;
  padding: 12px;
}
.upload-card a {
  color: #bfdbfe;
  word-break: break-all;
  text-decoration: none;
}
.upload-card .meta { color: var(--muted); font-size: 12px; margin-top: 6px; }
.upload-actions {
  display: flex;
  gap: 8px;
  margin-top: 10px;
  flex-wrap: wrap;
}
.delete-file-btn {
  background: rgba(239, 68, 68, 0.16);
  border: 1px solid rgba(248, 113, 113, 0.3);
  color: #fecaca;
  padding: 8px 12px;
  border-radius: 12px;
}

.confirm-modal {
  position: fixed;
  inset: 0;
  background: rgba(2, 6, 23, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 100;
}
.confirm-modal.hidden { display: none; }
.confirm-card {
  width: min(92vw, 420px);
  background: #0f172a;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px;
  box-shadow: var(--shadow);
}
.confirm-card h3 { margin: 0 0 10px; }
.confirm-card p { margin: 0; color: var(--muted); }
.confirm-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 18px;
}

@media (max-width: 900px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar {
    position: static;
    inset: auto;
    width: 100%;
    z-index: auto;
    transform: none;
    transition: none;
    border-right: 0;
    border-bottom: 1px solid var(--line);
    padding-bottom: 12px;
  }
  .sidebar.open { transform: none; }
  .mobile-toggle { display: none; }
  .main-panel { padding: 12px; }
  .topbar { flex-direction: column; align-items: stretch; }
  .status-wrap { justify-content: space-between; }
  .section-title-row { flex-direction: column; align-items: flex-start; }
  .editor { min-height: 38vh; }
  .bottom-panels { grid-template-columns: 1fr; }
}