/* ── Letters 信件面板 ── */
.letters-panel {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: var(--bg-primary);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  will-change: transform;
}

@media (min-width: 768px) {
  .letters-panel {
    right: auto;
    width: 480px;
    border-right: 1px solid var(--border);
    box-shadow: var(--shadow-lg, 0 8px 28px rgba(31,30,29,0.10));
  }
}

.letters-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--bg-primary);
  z-index: 10;
}

.letters-back {
  background: none;
  border: none;
  font-size: 1.4rem;
  cursor: pointer;
  color: var(--text-primary);
  padding: 4px 8px;
  border-radius: 6px;
}
.letters-back:hover { background: var(--bg-hover); }

.letters-title {
  font-size: 1.1rem;
  font-weight: 600;
  flex: 1;
  color: var(--text-primary);
}

.letters-compose-btn {
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 6px 14px;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  font-weight: 500;
}
.letters-compose-btn:hover { opacity: 0.9; }

.letters-body {
  flex: 1;
  padding: 16px 20px;
  overflow-y: auto;
}

/* ── 信件列表 ── */
.letters-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.letter-card {
  background: var(--card-bg);
  border-radius: var(--card-radius);
  padding: 16px;
  cursor: pointer;
  transition: background 0.15s;
}
.letter-card:hover { background: var(--bg-hover); }

.letter-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.letter-card-author {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-primary);
}
.letter-card-author.is-shen { color: var(--accent); }
.letter-card-author.is-dukou { color: var(--text-secondary, #666); }

.letter-card-date {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.letter-card-title {
  font-size: 0.95rem;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.letter-card-preview {
  font-size: 0.85rem;
  color: var(--text-secondary, #666);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ── 待拆信提示 ── */
.letters-pending {
  background: var(--bg-secondary);
  border-radius: 10px;
  padding: 12px 16px;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
}

/* ── 空状态 ── */
.letters-empty {
  text-align: center;
  color: var(--text-muted);
  padding: 48px 20px;
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ── 写信面板 ── */
.compose-overlay {
  position: fixed;
  inset: 0;
  z-index: 400;
  background: var(--bg-primary);
  display: flex;
  flex-direction: column;
}

@media (min-width: 768px) {
  .compose-overlay {
    right: auto;
    width: 480px;
    border-right: 1px solid var(--border);
  }
}

.compose-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}

.compose-cancel {
  background: none;
  border: none;
  font-size: 0.9rem;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px 8px;
}

.compose-send {
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 6px 16px;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  font-weight: 500;
  margin-left: auto;
}
.compose-send:disabled { opacity: 0.5; cursor: not-allowed; }

.compose-body {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.compose-field label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.compose-field input,
.compose-field textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 0.9rem;
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-family: inherit;
  resize: none;
}
.compose-field textarea {
  min-height: 200px;
  line-height: 1.6;
}
.compose-field input:focus,
.compose-field textarea:focus {
  outline: none;
  border-color: var(--accent);
}
.compose-field input[type="datetime-local"] {
  -webkit-appearance: none;
  min-height: 42px;
}
.compose-random-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 8px;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card-bg);
  color: var(--text-primary);
  font-size: 0.85rem;
  cursor: pointer;
  font-family: inherit;
}
.compose-random-btn:hover {
  border-color: var(--accent);
  background: var(--bg-hover);
}
.compose-random-btn:active { opacity: 0.8; }

/* ── 信件详情 ── */
.letter-detail {
  padding: 24px 20px;
}

.letter-detail-header {
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-light);
}

.letter-detail-title {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.letter-detail-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.letter-detail-content {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--text-primary);
  white-space: pre-wrap;
  word-break: break-word;
}

/* ── 导航红点 ── */
.feature-nav-badge {
  margin-left: auto;
  min-width: 20px;
  height: 20px;
  border-radius: 10px;
  background: var(--danger);
  color: #fff;
  font-size: 0.7rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 5px;
  line-height: 1;
}
.feature-nav-badge.hidden { display: none; }