/* 词以类聚：左树右栏；点枝干出词墙、点词出卡不刷新；无 JS 时仍可原生 details 浏览。 */
.tree-hero {
  padding: 22px 26px;
  margin: 0 0 20px;
  background:
    radial-gradient(ellipse at 92% 8%, #e8f5db, transparent 60%),
    linear-gradient(120deg, #f1f8ea, #eaf3e0);
  border: 1px solid #cfe3c0;
  border-radius: 22px;
}
.tree-hero-copy .eyebrow { margin-bottom: 6px; }
.tree-hero-copy h1 { margin: 0 0 8px; font-size: clamp(32px, 3.6vw, 44px); }
.tree-hero-tag { margin: 0 0 18px; color: var(--muted, #586b62); font-size: 17px; line-height: 1.7; }
.tree-modes { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.tree-modes a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border: 1px solid #bcd9a8;
  border-radius: 16px;
  background: var(--white, #fff);
  line-height: 1.5;
}
.tree-mode-icon { flex-shrink: 0; font-size: 28px; }
.tree-modes b { font-size: 20px; }
.tree-modes small { display: block; font-size: 15px; color: var(--muted, #586b62); }
.tree-modes a:hover { border-color: var(--green, #22634c); }
.tree-modes a[aria-current] { border-color: var(--green, #22634c); background: var(--green, #22634c); color: #fff; }
.tree-modes a[aria-current] small { color: #ecf7ea; }

.tree-root-chips { display: flex; flex-wrap: wrap; gap: 8px; padding: 14px 16px; margin: 0 0 20px; border: 1px solid #d8ecd3; border-radius: 18px; background: #f4faef; }
.tree-root-chips .chip { display: inline-flex; align-items: center; gap: 6px; min-height: 40px; padding: 6px 14px; border: 1px solid #d5e0ca; border-radius: 12px; background: var(--white, #fff); color: #3d4750; font-size: 16px; }
.tree-root-chips .chip i { font-style: normal; color: var(--muted, #586b62); font-size: 13px; }
.tree-root-chips .chip:hover { border-color: var(--green, #22634c); }
.tree-root-chips .chip.on { border-color: var(--green, #22634c); background: var(--green, #22634c); color: #fff; }
.tree-root-chips .chip.on i { color: #d9ecda; }

.tree-shell { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(280px, 1fr); gap: 22px; align-items: start; }
.tree-board { min-width: 0; padding: 18px 20px; border: 1px solid var(--line, #dce6d9); border-radius: 20px; background: var(--white, #fff); }
.tree-title { margin: 0 0 10px; font-size: 24px; }
.tree-title .muted { font-size: 16px; font-weight: 500; }

.tree-nodes { list-style: none; margin: 0; padding-left: 18px; }
.tree-nodes > li { position: relative; }
.tree-nodes > li::before { content: ""; position: absolute; left: -10px; top: 0; bottom: 0; border-left: 2px solid #e3ecdc; }
.tree-branch details { margin: 3px 0; }
.tree-branch summary { display: inline-flex; align-items: center; gap: 8px; cursor: pointer; list-style: none; padding: 5px 10px; border-radius: 10px; font-size: 17px; font-weight: 700; color: #234b38; }
.tree-branch summary::-webkit-details-marker { display: none; }
.tree-branch summary::before { content: "▸"; color: var(--green, #22634c); transition: transform .15s; }
.tree-branch details[open] > summary::before { transform: rotate(90deg); }
.tree-branch summary:hover { background: #eef5e6; }
.tree-branch-name i { margin-left: 6px; font-style: normal; font-size: 13px; font-weight: 500; }
.tree-branch-en { margin-left: 6px; font-style: normal; font-size: 13px; font-weight: 500; color: #7a8a6e; }
.tree-family-tip { margin-bottom: 12px; color: var(--muted, #586b62); font-size: 16px; }
.tree-shell-spelling .tree-branch-name [lang="en"] { font-size: 20px; }
.tree-shell .tree-family-sound { color: #57517d; font-size: 16px; }

.tree-board-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; margin-bottom: 10px; }
.tree-board-head .tree-title { margin: 0; }
.tree-tools { display: flex; gap: 8px; }
.tree-tool { padding: 6px 12px; border: 1px solid #d5e0ca; border-radius: 10px; background: #fff; color: #3d4750; font-size: 14px; cursor: pointer; }
.tree-tool:hover { border-color: var(--green, #22634c); background: #eef5e6; }

/* 词墙：任一枝干一点，右侧按子枝分组平铺全部后代词 */
.tree-wall { padding: 18px 20px; border: 1px solid var(--line, #dce6d9); border-radius: 20px; background: var(--white, #fff); }
.tree-crumb { display: flex; align-items: center; flex-wrap: wrap; gap: 6px; margin: 0; color: var(--muted, #586b62); font-size: 14px; }
.tree-crumb-sep { color: #b9c4ae; }
.tree-crumb-here { color: var(--ink, #233e37); font-weight: 700; }
.tree-filter { width: 100%; box-sizing: border-box; margin-top: 12px; padding: 9px 13px; border: 1px solid #d9e1cf; border-radius: 12px; background: #f9fbf5; font-size: 15px; color: var(--ink, #233e37); }
.tree-filter:focus { outline: 2px solid #bcd9a8; border-color: var(--green, #22634c); }
.tree-wall-groups { display: flex; flex-direction: column; gap: 16px; margin-top: 14px; }
.tree-wall-group-title { display: flex; align-items: baseline; gap: 6px; margin: 0 0 8px; font-size: 15px; font-weight: 700; color: #234b38; }
.tree-wall-group-title i { font-style: normal; font-size: 13px; font-weight: 500; color: var(--muted, #586b62); }
.tree-wall-words { display: flex; flex-wrap: wrap; gap: 8px; }
.tree-wall .tree-word { display: inline-flex; flex-direction: column; align-items: flex-start; gap: 1px; min-width: 86px; padding: 7px 12px; }
.tree-wall .tree-word[hidden] { display: none; }
.tree-wall .tree-word b { font-size: 16px; font-weight: 700; }
.tree-wall .tree-word i { font-style: normal; font-size: 12px; color: var(--muted, #586b62); }
.tree-shell-spelling .tree-wall .tree-word b { font-size: 18px; }
.tree-shell-spelling .tree-wall .tree-word i { font-size: 14px; }
.tree-wall .tree-word.on i { color: #d9ecda; }
.tree-wall-entry {
  display: inline-grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  min-width: min(128px, 100%);
  max-width: 100%;
  border: 1px solid #d9e1cf;
  border-radius: 16px;
  background: #f9fbf5;
}
.tree-wall-entry[hidden] { display: none; }
.tree-wall-entry .tree-word { min-width: 0; padding: 7px 10px; border: 0; background: transparent; overflow-wrap: anywhere; }
.tree-wall-entry .tree-word:hover { background: #eef5e6; }
.tree-wall-ipa { color: #57517d; font-size: 15px; font-weight: 600; }

.tree-node-words { display: flex; flex-wrap: wrap; gap: 7px; margin: 6px 0 8px 14px; }
.tree-root-words { margin-left: 0; }
.tree-word { display: inline-block; padding: 5px 12px; border: 1px solid #d9e1cf; border-radius: 16px; background: #f9fbf5; color: var(--ink, #233e37); font-size: 16px; }
.tree-word:hover { border-color: var(--green, #22634c); background: #eef5e6; }
.tree-word.on { border-color: var(--green, #22634c); background: var(--green, #22634c); color: #fff; font-weight: 700; }
.tree-word-ending { color: #275e49; background: #dff2cc; border-radius: .2em; font-weight: 800; }
.tree-word.on .tree-word-ending { color: #e4ffc9; background: transparent; }

.tree-word-panel { position: sticky; top: 24px; max-height: calc(100vh - 48px); overflow-y: auto; padding: 2px; }
.tree-word-card { padding: 26px 24px; border: 1px solid var(--line, #dce6d9); border-radius: 20px; background: var(--white, #fff); text-align: center; }
.tree-word-emoji { margin: 0; font-size: 54px; }
.tree-word-headline { display: flex; align-items: center; justify-content: center; gap: 12px; margin: 8px 0 0; }
.tree-word-headline b { font-size: 38px; font-weight: 900; letter-spacing: .01em; }
.say-chip { display: grid; place-items: center; width: 46px; height: 46px; border: 1px solid #cfe0c2; border-radius: 13px; background: #fff; font-size: 19px; }
.say-chip:hover { background: #eef6e6; }
.tree-wall-say { width: 44px; height: 44px; margin-inline-end: 8px; font-size: 18px; }
.tree-word-ipa { margin: 6px 0 0; color: #57517d; font-size: 21px; font-weight: 650; }
.tree-word-zh { margin: 10px 0 0; font-size: 23px; font-weight: 700; color: #33404d; }
.tree-word-scene { margin: 8px 0 0; color: var(--muted, #586b62); font-size: 16px; }
.tree-word-status { margin: 8px 0 0; color: #a3332a; font-size: 14px; }
.tree-word-actions { display: flex; flex-direction: column; gap: 8px; margin-top: 16px; }
.tree-word-actions .button { justify-content: center; }
.tree-word-actions .ghost { background: #fff; color: var(--green, #22634c); }
.tree-word-empty { padding: 18px; border: 2px dashed #dcead2; border-radius: 16px; color: var(--muted, #586b62); font-size: 16px; line-height: 1.8; text-align: center; }
.tree-word-empty b { color: var(--green, #22634c); }
.tree-source { margin: 22px 2px 0; color: var(--muted, #586b62); font-size: 13px; line-height: 1.7; }

@media (max-width: 900px) {
  .tree-shell { grid-template-columns: minmax(0, 1fr); }
  .tree-word-panel { position: static; }
}
@media (max-width: 560px) {
  .tree-hero { padding: 16px; }
  .tree-modes { grid-template-columns: minmax(0, 1fr); }
}
@media print {
  .tree-modes, .tree-root-chips, .tree-word-actions, .say-chip, .back { display: none !important; }
  .tree-shell { display: block; }
}