:root {
  --ink: #172039;
  --muted: #6f7890;
  --violet: #f05138;
  --violet-dark: #ca442f;
  --violet-soft: #fdeae7;
  --accent-light: #f26650;
  --accent-glow: rgba(240, 81, 56, .28);
  --accent-selection: rgba(240, 81, 56, .48);
  --accent-ambient: rgba(240, 81, 56, .13);
  --accent-ambient-soft: rgba(240, 81, 56, .08);
  --tree-color: #f05138;
  --tree-light: #f26650;
  --tree-highlight: #f47b68;
  --tree-deep: #c0412d;
  --tree-dark: #953223;
  --tree-component: #f15d46;
  --tree-shadow: rgba(240, 81, 56, .26);
  --tree-line: #f69384;
  --line: #d9ddea;
  --paper: #fbfbfd;
  --panel: rgba(255, 255, 255, 0.9);
  --shadow: 0 22px 65px rgba(240, 81, 56, 0.12);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background: #f6f6fa;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans TC", sans-serif;
  overflow-x: hidden;
}

button, textarea { font: inherit; }
button { color: inherit; }

.ambient {
  position: fixed;
  z-index: -1;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  filter: blur(1px);
  pointer-events: none;
}

.ambient-two { top: 440px; left: -340px; background: var(--accent-ambient-soft); }

.topbar {
  height: 74px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0 4.5vw;
  border-bottom: 1px solid rgba(23, 32, 57, 0.08);
  background: rgba(248, 248, 251, 0.78);
  backdrop-filter: blur(18px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  width: fit-content;
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -0.03em;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  color: white;
  border-radius: 10px;
  background: linear-gradient(145deg, var(--accent-light), var(--violet-dark));
  box-shadow: 0 7px 16px var(--accent-glow);
}

.brand-mark svg { width: 21px; fill: none; stroke: currentColor; stroke-width: 1.7; }
.header-copy { color: #8b91a2; font-size: 12px; font-weight: 600; letter-spacing: .06em; }

.top-actions { display: flex; align-items: center; justify-self: end; gap: 14px; }
.language-switch { display: flex; padding: 3px; border: 1px solid #dfe1e9; border-radius: 9px; background: rgba(255,255,255,.68); }
.language-switch button { min-width: 38px; height: 25px; padding: 0 8px; color: #7d8497; border: 0; border-radius: 6px; background: transparent; font-size: 10px; font-weight: 800; cursor: pointer; transition: color .18s, background .18s, box-shadow .18s; }
.language-switch button:hover { color: var(--violet); }
.language-switch button[aria-pressed="true"] { color: white; background: var(--violet); box-shadow: 0 3px 9px var(--accent-glow); }

main { width: min(1420px, 92vw); margin: 0 auto; padding: 74px 0 54px; }

.hero { display: grid; grid-template-columns: minmax(0, 760px) minmax(340px, 500px); align-items: center; justify-content: space-between; gap: clamp(30px, 5vw, 84px); margin-bottom: 45px; }
.hero-copy { min-width: 0; }
.eyebrow { display: flex; align-items: center; gap: 10px; color: var(--violet); font-size: 11px; font-weight: 800; letter-spacing: .15em; text-transform: uppercase; }
.eyebrow > span:first-child { width: 24px; height: 2px; flex: 0 0 24px; background: var(--violet); }

.hero h1 {
  margin: 18px 0 16px;
  color: #1b2137;
  font-size: clamp(40px, 5vw, 68px);
  line-height: 1.06;
  letter-spacing: -.065em;
}
.hero h1 em { color: var(--violet); font-style: normal; font-weight: 500; }
.hero p { max-width: 620px; margin: 0; color: var(--muted); font-size: 15px; line-height: 1.85; }
.hero-art { position: relative; isolation: isolate; width: 100%; margin: -28px 0 -20px; justify-self: end; }
.hero-art img { position: relative; z-index: 1; display: block; width: 100%; height: auto; border-radius: 42px; -webkit-mask-image: radial-gradient(ellipse 78% 82% at 50% 50%, #000 70%, transparent 100%); mask-image: radial-gradient(ellipse 78% 82% at 50% 50%, #000 70%, transparent 100%); filter: drop-shadow(0 22px 28px var(--accent-ambient)); }
.hero-art-glow { position: absolute; z-index: 0; inset: 18% 8% 8%; border-radius: 50%; background: var(--accent-ambient); filter: blur(55px); }

.workspace { display: grid; grid-template-columns: minmax(360px, .78fr) minmax(560px, 1.22fr); gap: 22px; align-items: stretch; }
.panel { min-width: 0; border: 1px solid rgba(37, 44, 75, .1); border-radius: 18px; background: var(--panel); box-shadow: var(--shadow); overflow: hidden; }

.panel-header { min-height: 76px; display: flex; align-items: center; justify-content: space-between; padding: 0 23px; border-bottom: 1px solid #e6e8f0; }
.panel-header > div:first-child { display: flex; align-items: center; gap: 12px; }
.panel-header h2 { margin: 0; font-size: 14px; letter-spacing: -.02em; }
.step { display: grid; place-items: center; width: 30px; height: 30px; color: var(--violet); border-radius: 9px; background: var(--violet-soft); font-family: ui-monospace, "SFMono-Regular", Menlo, monospace; font-size: 10px; font-weight: 500; }
.editor-actions, .toolbar, .diagram-tools { display: flex; align-items: center; gap: 6px; }
.diagram-tools { gap: 12px; }

.text-button, .icon-button { border: 0; background: transparent; cursor: pointer; }
.text-button { padding: 8px 10px; color: var(--violet); font-size: 11px; font-weight: 800; }
.icon-button { display: grid; place-items: center; width: 31px; height: 31px; border-radius: 8px; color: #767e94; font-size: 18px; transition: .18s ease; }
.icon-button:hover { color: var(--violet); background: var(--violet-soft); }
.icon-button svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.code-wrap { position: relative; display: grid; grid-template-columns: 46px 1fr; height: 450px; background: #191b27; overflow: hidden; }
.line-numbers { padding: 21px 11px 21px 0; color: #555969; border-right: 1px solid #2a2d3a; font: 12px/1.75 ui-monospace, "SFMono-Regular", Menlo, monospace; text-align: right; user-select: none; overflow: hidden; }
#codeInput { width: 100%; height: 100%; padding: 20px; color: #d8daea; border: 0; outline: 0; resize: none; background: transparent; caret-color: var(--accent-light); font: 12px/1.75 ui-monospace, "SFMono-Regular", Menlo, monospace; tab-size: 4; white-space: pre; overflow: auto; }
#codeInput::selection { background: var(--accent-selection); }

.editor-footer, .diagram-footer { height: 42px; display: flex; align-items: center; padding: 0 22px; color: #8c93a5; border-top: 1px solid #e6e8f0; font-size: 10px; font-weight: 700; }
.editor-footer { justify-content: space-between; }
.editor-footer i { display: inline-block; width: 6px; height: 6px; margin-right: 6px; border-radius: 50%; background: #ea8d39; box-shadow: 0 0 0 3px rgba(234, 141, 57, .13); }
.generate-button { width: 100%; height: 56px; display: flex; align-items: center; justify-content: center; gap: 12px; color: white; border: 0; background: linear-gradient(100deg, var(--violet-dark), var(--accent-light)); font-size: 12px; font-weight: 800; cursor: pointer; transition: filter .2s, transform .15s; }
.generate-button:hover { filter: brightness(1.07); }
.generate-button:active { transform: scale(.995); }
.generate-button svg { width: 17px; fill: none; stroke: currentColor; stroke-width: 1.8; }

.toolbar { padding: 3px; border: 1px solid #e1e3eb; border-radius: 10px; background: #f9f9fc; }
.toolbar .icon-button { width: 28px; height: 26px; font-size: 15px; }
.toolbar > span:not(.divider) { width: 43px; color: #757c90; font: 9px ui-monospace, "SFMono-Regular", Menlo, monospace; text-align: center; }
.toolbar .divider { width: 1px; height: 17px; margin: 0 2px; background: #dfe1e9; }
.fit-icon svg { width: 13px; }
.name-only-control { display: flex; align-items: center; gap: 7px; color: #70788e; font-size: 10px; font-weight: 700; cursor: pointer; user-select: none; white-space: nowrap; }
.name-only-control input { position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.switch-track { position: relative; width: 31px; height: 18px; flex: 0 0 auto; border: 1px solid #d6d9e4; border-radius: 999px; background: #e7e9f0; transition: background .18s, border-color .18s; }
.switch-track span { position: absolute; top: 2px; left: 2px; width: 12px; height: 12px; border-radius: 50%; background: white; box-shadow: 0 1px 4px rgba(24, 29, 53, .22); transition: transform .18s; }
.name-only-control input:checked + .switch-track { border-color: var(--violet); background: var(--violet); }
.name-only-control input:checked + .switch-track span { transform: translateX(13px); }
.name-only-control input:focus-visible + .switch-track { outline: 2px solid var(--accent-glow); outline-offset: 2px; }
.color-control { display: flex; align-items: center; gap: 7px; color: #70788e; font-size: 10px; font-weight: 700; cursor: pointer; white-space: nowrap; }
.color-control input { width: 28px; height: 28px; padding: 3px; border: 1px solid #dfe1e9; border-radius: 9px; outline: 0; background: #f9f9fc; cursor: pointer; }
.color-control input::-webkit-color-swatch-wrapper { padding: 0; }
.color-control input::-webkit-color-swatch { border: 0; border-radius: 5px; }
.color-control input::-moz-color-swatch { border: 0; border-radius: 5px; }
.color-control input:focus-visible { border-color: var(--tree-color); box-shadow: 0 0 0 2px color-mix(in srgb, var(--tree-color) 24%, transparent); }

.diagram-panel { display: flex; flex-direction: column; }
.diagram-canvas { position: relative; flex: 1; min-height: 508px; background-color: #fafafd; background-image: radial-gradient(#d9dbe7 0.7px, transparent 0.7px); background-size: 17px 17px; overflow: auto; }
.tree-stage { min-width: 100%; min-height: 100%; width: max-content; padding: 52px 68px; transform-origin: 40px 40px; transition: transform .18s ease; }

.tree, .tree ul { position: relative; margin: 0; padding: 0; list-style: none; }
.tree ul { margin-left: 92px; }
.children-branch { display: grid; grid-template-rows: 1fr; opacity: 1; transform: translateY(0); transform-origin: top; transition: grid-template-rows .32s cubic-bezier(.2, .8, .2, 1), opacity .22s ease, transform .32s cubic-bezier(.2, .8, .2, 1); }
.children-branch > ul { min-height: 0; overflow: hidden; }
.tree li { position: relative; padding: 11px 0 11px 72px; }
.tree > li { padding-left: 0; }
.tree li::before { content: ""; position: absolute; top: 0; bottom: 0; left: 0; width: 3px; border-radius: 2px; background: var(--tree-line); }
.tree li::after { content: ""; position: absolute; top: 33px; left: 0; width: 50px; height: 3px; border-radius: 2px; background: var(--tree-line); }
.tree li:last-child::before { bottom: auto; height: 36px; }
.tree > li::before, .tree > li::after { display: none; }

.node-row { position: relative; display: flex; align-items: center; min-height: 46px; }
.tree li > .node-row::before { content: ""; position: absolute; z-index: 2; top: 17px; left: -23px; width: 0; height: 0; border-top: 6px solid transparent; border-bottom: 6px solid transparent; border-left: 11px solid var(--tree-line); }
.tree > li > .node-row::before { display: none; }
.tree-stage.tree-entering .tree li::before,
.children-branch.is-expanding li::before { transform-origin: top; animation: connector-grow-vertical .3s cubic-bezier(.2, .8, .2, 1) both; }
.tree-stage.tree-entering .tree li::after,
.children-branch.is-expanding li::after { transform-origin: left center; animation: connector-grow-horizontal .32s .1s cubic-bezier(.2, .8, .2, 1) both; }
.tree-stage.tree-entering .tree li > .node-row::before,
.children-branch.is-expanding li > .node-row::before { transform-origin: center; animation: connector-arrow-pop .18s .36s cubic-bezier(.2, .9, .3, 1.25) both; }

@keyframes connector-grow-vertical {
  from { opacity: 0; transform: scaleY(0); }
  to { opacity: 1; transform: scaleY(1); }
}

@keyframes connector-grow-horizontal {
  from { opacity: 0; transform: scaleX(0); }
  to { opacity: 1; transform: scaleX(1); }
}

@keyframes connector-arrow-pop {
  from { opacity: 0; transform: translateX(-8px) scale(.35); }
  to { opacity: 1; transform: translateX(0) scale(1); }
}

.view-node { position: relative; display: flex; align-items: center; gap: 10px; min-width: 166px; min-height: 46px; padding: 9px 14px; color: #35405f; border: 1px solid #dde0e9; border-radius: 11px; background: white; box-shadow: 0 7px 18px rgba(32, 38, 69, .08); cursor: default; transition: transform .18s, border-color .18s, box-shadow .18s; }
.view-node.has-children { color: white; border-color: transparent; background: linear-gradient(135deg, var(--tree-highlight) 0%, var(--tree-color) 52%, var(--tree-deep) 100%); box-shadow: 0 9px 20px var(--tree-shadow); cursor: pointer; }
.view-node.type-node { background: linear-gradient(135deg, var(--tree-dark) 0%, var(--tree-color) 58%, var(--tree-deep) 100%); box-shadow: 0 9px 22px var(--tree-shadow); }
.view-node.type-node .node-icon { background: rgba(255,255,255,.14); }
.view-node.component-node { background: linear-gradient(135deg, var(--tree-component) 0%, var(--tree-color) 55%, var(--tree-deep) 100%); box-shadow: 0 9px 20px var(--tree-shadow); }
.view-node:hover { transform: translateY(-1px); border-color: var(--tree-light); box-shadow: 0 9px 22px var(--tree-shadow); }
.node-icon { display: grid; place-items: center; width: 24px; height: 24px; border-radius: 7px; color: var(--violet); background: var(--violet-soft); font: 500 10px ui-monospace, "SFMono-Regular", Menlo, monospace; }
.has-children .node-icon { color: white; background: rgba(255,255,255,.17); }
.node-text { display: flex; min-width: 0; flex-direction: column; }
.node-name { font: 500 13px ui-monospace, "SFMono-Regular", Menlo, monospace; }
.node-detail { max-width: 160px; margin-top: 2px; color: #9a9fb0; font: 9px ui-monospace, "SFMono-Regular", Menlo, monospace; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tree-stage.names-only .node-detail { display: none; }
.has-children .node-detail { color: rgba(255,255,255,.65); }
.toggle { display: grid; place-items: center; width: 18px; height: 18px; margin-left: auto; border-radius: 5px; background: rgba(255,255,255,.18); font: 12px/1 ui-monospace, "SFMono-Regular", Menlo, monospace; }
.collapsed > .children-branch { grid-template-rows: 0fr; opacity: 0; transform: translateY(-7px); pointer-events: none; }
.collapsed > .node-row .view-node { background: linear-gradient(135deg, var(--tree-highlight) 0%, var(--tree-color) 52%, var(--tree-deep) 100%); }

.empty-state { position: absolute; inset: 0; display: grid; place-content: center; justify-items: center; color: #9a9fb1; text-align: center; }
.empty-state[hidden] { display: none; }
.empty-state > span { display: grid; place-items: center; width: 58px; height: 58px; margin-bottom: 15px; color: var(--violet); border-radius: 16px; background: var(--violet-soft); font: 16px ui-monospace, "SFMono-Regular", Menlo, monospace; }
.empty-state h3 { margin: 0 0 7px; color: #515a73; font-size: 14px; }
.empty-state p { margin: 0; font-size: 11px; }

.diagram-footer { gap: 20px; }
.legend { display: inline-block; width: 7px; height: 7px; margin-right: 5px; border-radius: 2px; }
.container-dot { background: var(--violet); }
.leaf-dot { border: 1px solid #aeb3c1; background: white; }
.stats { display: flex; gap: 17px; margin-left: auto; font-family: ui-monospace, "SFMono-Regular", Menlo, monospace; }
.hint { margin: 22px 0 0; color: #81889c; font-size: 11px; text-align: center; }
.hint > span { margin-right: 8px; padding: 3px 7px; color: var(--violet); border-radius: 5px; background: var(--violet-soft); font: 500 8px ui-monospace, "SFMono-Regular", Menlo, monospace; }
.hint b { display: inline-grid; place-items: center; width: 15px; height: 15px; color: white; border-radius: 4px; background: var(--violet); font: 10px ui-monospace, "SFMono-Regular", Menlo, monospace; }

@media (max-width: 960px) {
  .workspace { grid-template-columns: 1fr; }
  .hero { grid-template-columns: minmax(0, 1fr) minmax(280px, 360px); gap: 24px; }
  .diagram-canvas { min-height: 520px; }
  .header-copy { display: none; }
  .topbar { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .hero { grid-template-columns: 1fr; }
  .hero-art { width: min(430px, 92%); margin: -18px auto -8px; justify-self: center; }
}

@media (max-width: 580px) {
  main { width: 94vw; padding-top: 48px; }
  .topbar { padding: 0 4vw; }
  .brand { font-size: 14px; }
  .top-actions { gap: 8px; }
  .hero h1 { font-size: 42px; }
  .hero p { font-size: 13px; }
  .panel-header { padding: 0 15px; }
  .diagram-header { align-items: flex-start; min-height: 104px; padding-top: 16px; padding-bottom: 13px; }
  .diagram-tools { align-items: flex-end; flex-direction: column-reverse; gap: 7px; }
  .code-wrap { height: 390px; }
  .diagram-canvas { min-height: 460px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; animation: none !important; }
}