:root {
  --bg: #ecfeff;
  --panel: #ffffff;
  --line: #d9eef2;
  --text: #164e63;
  --muted: #457386;
  --accent: #0891b2;
  --accent-2: #0e7490;
  --accent-soft: #f0fdff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  height: 100vh;
  overflow: hidden;
}

.topbar {
  max-width: 1240px;
  height: 72px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand h1 {
  margin: 0;
  font-size: 32px;
  letter-spacing: -0.02em;
}

.brand .muted {
  margin: 6px 0 0;
}

.badge {
  font-size: 12px;
  font-weight: 700;
  color: #fafafa;
  background: var(--accent-2);
  border: 1px solid var(--accent-2);
  padding: 5px 10px;
  border-radius: 999px;
}

.layout {
  max-width: 1240px;
  height: calc(100vh - 72px);
  margin: 0 auto;
  padding: 0 20px;
  display: grid;
  grid-template-columns: minmax(320px, 42%) 1fr;
  gap: 12px;
  overflow: hidden;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
  box-shadow: 0 6px 24px rgba(8, 145, 178, 0.08);
  min-height: 0;
  overflow: hidden;
}

h1,
h2 {
  margin-top: 0;
}

.panel-head {
  margin-bottom: 10px;
}

.panel-head h2 {
  margin: 0;
  font-size: 18px;
}

.muted {
  color: var(--muted);
  margin-top: 2px;
}

label {
  display: block;
  margin-top: 8px;
  margin-bottom: 4px;
  font-size: 13px;
  font-weight: 600;
}

.field-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}

.meta {
  color: var(--muted);
  font-size: 12px;
}

input,
textarea,
button {
  width: 100%;
  border-radius: 10px;
  border: 1px solid var(--line);
  padding: 8px 10px;
  font-size: 13px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
}

textarea {
  resize: vertical;
  line-height: 1.5;
}

input:focus,
textarea:focus {
  outline: none;
  border-color: #7dd3e7;
  box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.15);
}

button {
  cursor: pointer;
  margin-top: 8px;
  font-weight: 700;
}

button:hover {
  filter: brightness(0.98);
}

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

button.primary:hover {
  background: var(--accent-2);
}

button.secondary {
  background: #fff;
  color: var(--text);
  border-color: var(--line);
}

button.secondary:hover {
  background: #f8fdff;
}

.subtle-btn {
  background: #fff;
  border-color: #a5dae6;
  color: var(--accent-2);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.65;
}

.actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.grid2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.cover-tools {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  align-items: center;
}

.cover-tools button {
  margin-top: 0;
  width: auto;
  white-space: nowrap;
}

.status {
  min-height: 18px;
  margin-top: 6px;
  color: var(--accent-2);
  font-weight: 500;
  font-size: 12px;
}

.small {
  font-size: 12px;
  margin: 0 0 6px;
}

.body-split {
  display: grid;
  grid-template-columns: 1fr 0.9fr;
  gap: 10px;
  align-items: stretch;
  min-height: 0;
}

.body-split textarea {
  min-height: 170px;
  max-height: 240px;
}

.preview-panel {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.markdown-preview {
  flex: 1;
  min-height: 170px;
  max-height: 240px;
  overflow: auto;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fafcfb;
  font-size: 14px;
  line-height: 1.65;
}

.markdown-preview h2 {
  font-size: 1.15rem;
  margin: 1em 0 0.5em;
  color: #111827;
}

.markdown-preview h3 {
  font-size: 1.05rem;
  margin: 0.9em 0 0.4em;
}

.markdown-preview p {
  margin: 0.5em 0;
}

.markdown-preview ul,
.markdown-preview ol {
  margin: 0.4em 0 0.6em 1.2em;
  padding: 0;
}

.markdown-preview li {
  margin: 0.25em 0;
}

@media (max-width: 960px) {
  body {
    overflow: auto;
  }

  .layout {
    grid-template-columns: 1fr;
    height: auto;
  }

  .body-split {
    grid-template-columns: 1fr;
  }

  .topbar {
    align-items: flex-start;
    gap: 8px;
    flex-direction: column;
  }
}