/* 方法图谱：原生 SVG、有限动效与渐进增强。 */
button, output { font: inherit; }
button { color: inherit; }
button:not(:disabled), .scene-method-link { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible, [tabindex="0"]:focus-visible {
  outline: 2px solid #ff9577;
  outline-offset: 5px;
}
button:disabled { opacity: .35; cursor: default; }
.diagram-only-js { display: none; }
.methodology-ready .diagram-only-js { display: flex; }
.methodology-ready .method-fallback { display: none; }
.site-header::after {
  content: ""; position: absolute; bottom: -1px; left: 0; height: 2px;
  width: calc(var(--reading-progress, 0) * 100%); background: #ff633c;
  pointer-events: none;
}
.nav-links { gap: clamp(17px, 1.8vw, 26px); font-size: 14px; }
.nav-links a[aria-current="location"] { color: #fff; border-bottom-color: #ff633c; }

/* 从具体场景进入方法；文字与行动各占一层。 */
.scene-heading { max-width: 940px; }
.scene-heading h2 { max-width: 920px; }
.scene-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.scene-grid .fit-item {
  position: relative; display: flex; flex-direction: column; align-items: flex-start;
  padding: 34px 36px 29px; min-height: 300px; overflow: hidden;
  background: radial-gradient(ellipse at 100% 0, rgba(255,255,255,.035), transparent 60%), #202225;
  transition: border-color .25s, transform .25s;
}
.scene-grid .item-index { font-size: 11px; font-weight: 500; letter-spacing: .1em; color: #b0b2b7; }
.scene-grid h3 { margin-top: 23px; margin-bottom: 15px; font-size: clamp(23px, 2.15vw, 29px); line-height: 1.45; font-weight: 650; letter-spacing: -.025em; }
.scene-grid .fit-item p { max-width: 390px; font-size: 14px; line-height: 1.85; color: #b9bbc1; text-wrap: pretty; }
.scene-method-link { display: flex; align-items: center; gap: 26px; margin-top: auto; padding-top: 25px; font-size: 12px; font-weight: 500; color: #ff9c82; }
.scene-method-link span { font-size: 18px; transition: transform .25s; }
@media (hover: hover) {
  .scene-grid .fit-item:hover { transform: translateY(-3px); border-color: rgba(255, 157, 128, .35); }
  .scene-method-link:hover span { transform: translate(2px,-2px); }
}

/* 图谱像一本展开的工作图册，背景纹理只留在纸面下。 */
.methodology-section {
  border-block: 1px solid rgba(255,255,255,.08);
  background: radial-gradient(ellipse at 85% 35%, rgba(255,99,60,.035), transparent 58%), linear-gradient(120deg,#1c1e21,#17191c);
}
.methodology-heading { display: flex; align-items: flex-end; justify-content: space-between; max-width: none; gap: 45px; }
.methodology-heading h2 { max-width: 730px; }
.methodology-heading .methodology-heading-note { flex: 0 0 auto; border-left: 1px solid rgba(255,255,255,.17); padding: 3px 0 3px 25px; margin: 0 0 6px; }
.methodology-heading-note strong { display: block; margin-bottom: 9px; color: #ededee; font-size: 13px; font-weight: 550; letter-spacing: .04em; }
.methodology-heading-note span { font-size: 12px; line-height: 1.85; color: #a8abb2; }
.methodology-library { margin-top: 43px; }
.methodology-categories { gap: 32px; border-bottom: 1px solid rgba(255,255,255,.14); }
.methodology-categories button {
  position: relative; display: flex; gap: 10px; align-items: baseline; padding: 0 0 16px;
  border: 0; border-bottom: 2px solid transparent; margin-bottom: -1px;
  background: transparent; color: #9b9fa7; font-size: 14px; font-weight: 500; cursor: pointer;
  transition: color .2s, border-color .2s;
}
.methodology-categories button span { font-size: 10px; font-variant-numeric: tabular-nums; color: #7d828b; }
.methodology-categories button[aria-pressed="true"] { color: #fff; border-bottom-color: #ff633c; }
.methodology-categories button[aria-pressed="true"] span { color: #ff9476; }
.methodology-category-hint { display: none; }
.diagram-tabs { flex-wrap: wrap; align-items: center; gap: 9px; margin-block: 22px; min-height: 40px; }
.diagram-tab { display: inline-flex; align-items: center; gap: 9px; border: 1px solid rgba(255,255,255,.13); border-radius: 5px; background: rgba(255,255,255,.018); padding: 9px 13px; color: #b7bac1; font-size: 12px; cursor: pointer; }
.diagram-tab span { color: #818691; font-size: 10px; font-variant-numeric: tabular-nums; }
.diagram-tab[aria-pressed="true"] { color: #fff; background: rgba(255,99,60,.08); border-color: rgba(255,136,104,.5); }
.diagram-tab[aria-pressed="true"] span { color: #ff9476; }
.diagram-tab[hidden] { display: none; }
.diagram-panel { overflow: hidden; border: 1px solid #3b3f46; border-radius: 10px; background: #222428; box-shadow: 0 28px 70px rgba(0,0,0,.17), inset 0 1px 0 rgba(255,255,255,.045); }
.diagram-panel-heading { display: flex; justify-content: space-between; align-items: flex-start; gap: 25px; padding: 31px 35px 25px; border-bottom: 1px solid rgba(255,255,255,.07); }
.diagram-kicker { display: flex; align-items: baseline; gap: 14px; font-size: 11px; color: #b0b4bc; letter-spacing: .06em; }
.diagram-kicker > span:first-child { color: #ff9577; font-size: 12px; font-variant-numeric: tabular-nums; }
.diagram-panel-heading h3 { margin-top: 12px; font-size: clamp(20px,2vw,27px); line-height: 1.5; font-weight: 600; letter-spacing: -.015em; text-wrap: balance; }
.diagram-panel-heading #diagram-purpose { margin-top: 10px; color: #aeb2ba; font-size: 13px; line-height: 1.85; max-width: 730px; text-wrap: pretty; }
.diagram-expand { flex-shrink: 0; gap: 7px; align-items: center; border: 1px solid rgba(255,255,255,.22); border-radius: 5px; background: transparent; padding: 9px 12px; font-size: 12px; color: #dedfe2; cursor: pointer; }
.diagram-expand > span { font-size: 19px; line-height: 1; }
.diagram-canvas { overflow: auto; overscroll-behavior-x: contain; scrollbar-width: thin; scrollbar-color: #565c66 #232529; }
.method-diagram { display: block; width: 100%; height: auto; }
.diagram-canvas .method-diagram { min-width: 800px; }
.diagram-panel-footer { display: flex; align-items: center; justify-content: space-between; gap: 15px; padding: 15px 29px; border-top: 1px solid rgba(255,255,255,.08); background: rgba(0,0,0,.09); }
.diagram-credit { font-size: 10px; color: #858a95; letter-spacing: .035em; }
.diagram-hint { display: none; font-size: 10px; color: #9da2ab; }
.diagram-pagination { align-items: center; gap: 15px; margin-left: auto; }
.diagram-pagination button { border: 1px solid #41464f; background: transparent; width: 32px; height: 29px; border-radius: 4px; cursor: pointer; line-height: 1; }
.diagram-pagination > span { font-size: 10px; font-variant-numeric: tabular-nums; letter-spacing: .12em; color: #acb0b8; }
.methodology-note { max-width: 860px; margin-top: 19px; font-size: 11px; line-height: 1.9; color: #9297a1; text-wrap: pretty; }
.method-fallback { display: flex; flex-wrap: wrap; gap: 14px 25px; margin-top: 24px; color: #d4b1a8; font-size: 13px; }

/* 四步是一条可读的流程，而不是四块互不相连的说明。 */
.workflow { margin-top: 40px; }
.workflow-route { display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); gap: 24px; padding-bottom: 28px; }
.workflow-route > li { min-width: 0; position: relative; }
.workflow-route > li:not(:last-child)::after { content: ""; position: absolute; width: calc(100% - 10px); left: 52px; top: 24px; height: 1px; background: linear-gradient(90deg,#666c77,#3a3d43); z-index: -1; }
.workflow-step { position: relative; display: flex; align-items: flex-start; gap: 14px; width: 100%; padding: 0; border: none; background: transparent; text-align: left; cursor: pointer; }
.workflow-node { display: grid; place-items: center; flex: 0 0 48px; height: 48px; border: 1px solid #4b5059; border-radius: 50%; background: #22252a; color: #b3b7bf; font-size: 11px; letter-spacing: .06em; font-variant-numeric: tabular-nums; transition: border-color .3s, background .3s; }
.workflow-step strong { display: block; width: fit-content; padding: 0 7px; margin: 0 0 5px -7px; background: #191b1e; font-size: 20px; line-height: 1.5; font-weight: 550; }
.workflow-step small { display: block; font-size: 11px; color: #9197a2; line-height: 1.65; }
.workflow-step-arrow { display: none; }
.methodology-ready .workflow-step[aria-expanded="true"] .workflow-node { background: #ff633c; border-color: #ff8c6f; color: #171717; box-shadow: 0 0 25px rgba(255,99,60,.1); }
.methodology-ready .workflow-step[aria-expanded="true"] strong { color: #ff9c81; }
.workflow-panels { border: 1px solid #3b3f46; border-radius: 8px; background: linear-gradient(125deg,rgba(255,255,255,.032),transparent 65%), #202227; overflow: hidden; }
.workflow-panel { display: grid; grid-template-columns: 1.15fr 1fr; gap: 60px; padding: 37px 39px; }
.workflow-panel[hidden] { display: none; }
.workflow-panel-main .eyebrow { margin-bottom: 17px; font-size: 10px; color: #f99c84; }
.workflow-panel-main h3 { font-size: 25px; line-height: 1.5; font-weight: 600; letter-spacing: -.02em; text-wrap: balance; }
.workflow-panel-main > p:last-child { color: #b2b6be; font-size: 13px; line-height: 1.9; margin-top: 15px; max-width: 460px; text-wrap: pretty; }
.workflow-evidence { display: grid; gap: 19px; margin: 0; }
.workflow-evidence > div { border-left: 1px solid #4a505a; padding-left: 21px; }
.workflow-evidence dt { font-size: 10px; color: #9097a3; margin-bottom: 6px; letter-spacing: .05em; }
.workflow-evidence dd { margin: 0; color: #d9dce1; font-size: 13px; line-height: 1.85; text-wrap: pretty; }
.workflow-loop { margin-top: 18px; font-size: 11px; color: #989ea8; }
.workflow-loop > span { color: #ff9679; margin-right: 8px; font-size: 17px; vertical-align: -1px; }

/* 图册阅读模式，使用浏览器原生对话框与焦点管理。 */
body.diagram-open { overflow: hidden; }
.diagram-dialog { width: calc(100vw - 40px); max-width: 1600px; height: calc(100dvh - 40px); max-height: none; padding: 0; margin: auto; background: #1c1e22; color: #f6f6f6; border: 1px solid #535a66; border-radius: 10px; overflow: hidden; box-shadow: 0 30px 150px #000; }
.diagram-dialog[open] { display: flex; flex-direction: column; }
.diagram-dialog::backdrop { background: rgba(6,7,9,.88); backdrop-filter: blur(8px); }
.diagram-dialog-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 17px 24px; border-bottom: 1px solid #3c414a; flex-shrink: 0; }
.diagram-dialog-toolbar p { color: #989fab; font-size: 10px; letter-spacing: .07em; margin-bottom: 5px; }
.diagram-dialog-toolbar h2 { font-size: 18px; font-weight: 550; line-height: 1.5; }
.diagram-zoom-controls { display: flex; align-items: center; gap: 9px; margin-left: auto; }
.diagram-zoom-controls button, .diagram-close { display: grid; place-items: center; padding: 0 10px; height: 34px; min-width: 34px; border: 1px solid #464d58; border-radius: 4px; background: transparent; cursor: pointer; font-size: 14px; }
.diagram-zoom-controls output { width: 45px; text-align: center; font-size: 11px; color: #b4bac5; font-variant-numeric: tabular-nums; }
.diagram-zoom-controls [data-zoom-fit] { font-size: 11px; }
.diagram-close { border-color: transparent; font-size: 26px; font-weight: 300; }
.diagram-viewport { flex: 1; overflow: auto; min-height: 0; background: #212327; overscroll-behavior: contain; cursor: grab; scrollbar-color: #646c7a #24272d; touch-action: pan-x pan-y; }
.diagram-viewport.is-dragging { cursor: grabbing; user-select: none; }
.diagram-viewport svg { max-width: none; }
.diagram-dialog-footer { display: flex; justify-content: space-between; gap: 16px; padding: 12px 24px; font-size: 10px; color: #9ca3af; border-top: 1px solid #383e47; flex-shrink: 0; }
.diagram-dialog-footer a { color: #ffc1ae; }

/* 动效只在进入视野或切换图谱时播放一次。 */
@media (prefers-reduced-motion: no-preference) {
  .motion-ready [data-reveal] { opacity: 0; transform: translateY(18px); transition: opacity .65s ease, transform .65s cubic-bezier(.2,.7,.2,1); }
  .motion-ready [data-reveal].is-visible { opacity: 1; transform: none; }
  .method-diagram.is-entering .diagram-label { animation: diagram-label-in .5s both; animation-delay: calc(var(--label-order) * 13ms); transform-box: fill-box; transform-origin: center; }
  .method-diagram.is-entering .diagram-connector { animation: diagram-line-in .8s .1s both; }
  .workflow-panel.is-entering { animation: panel-in .4s both; }
}
@keyframes diagram-label-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@keyframes diagram-line-in { from { stroke-dasharray: 1; stroke-dashoffset: 1; } to { stroke-dasharray: 1; stroke-dashoffset: 0; } }
@keyframes panel-in { from { opacity: .3; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { animation: none !important; transition: none !important; } }

@media (max-width: 1180px) { .brand-sub { display: none; } }
@media (max-width: 980px) {
  .methodology-heading { align-items: flex-start; gap: 25px; }
  .methodology-heading .methodology-heading-note { border: none; padding: 0; }
  .methodology-heading-note span { display: none; }
  .methodology-categories { gap: 24px; }
  .workflow-panel { gap: 34px; padding: 30px; }
  .workflow-step { gap: 10px; }
  .workflow-step small { font-size: 10px; }
  .workflow-node { flex-basis: 41px; height: 41px; }
  .workflow-route > li:not(:last-child)::after { top: 20px; left: 45px; }
  .diagram-canvas .method-diagram { min-width: 0; }
}
@media (max-width: 720px) {
  .scene-grid { grid-template-columns: 1fr; gap: 14px; }
  .scene-grid .fit-item { padding: 27px 26px 24px; min-height: 270px; }
  .scene-grid h3 { font-size: 25px; margin-top: 18px; }
  .scene-grid .fit-item p { font-size: 13px; }
  .scene-method-link { font-size: 11px; padding-top: 21px; }
  .methodology-heading { display: block; }
  .methodology-heading .methodology-heading-note { margin-top: 20px; }
  .methodology-heading-note strong { font-size: 11px; color: #a4a9b3; }
  .methodology-library { margin-top: 28px; }
  .methodology-categories { gap: 22px; overflow: auto; scrollbar-width: none; padding-right: 1px; }
  .methodology-categories button { flex-shrink: 0; font-size: 12px; padding-bottom: 13px; gap: 7px; }
  .methodology-categories button span { font-size: 9px; }
  .methodology-ready .methodology-category-hint { display: block; margin-top: 10px; font-size: 9px; line-height: 1.6; color: #969ca6; text-align: right; }
  .methodology-category-hint span { color: #ff9c82; padding-left: 5px; }
  .diagram-tabs { gap: 7px; margin-block: 18px; }
  .diagram-tab { font-size: 11px; padding: 8px 10px; gap: 7px; }
  .diagram-panel-heading { padding: 24px 23px 22px; display: block; }
  .diagram-panel-heading h3 { font-size: 22px; margin-top: 11px; }
  .diagram-panel-heading #diagram-purpose { font-size: 12px; line-height: 1.85; }
  .diagram-kicker { font-size: 10px; gap: 11px; }
  .diagram-expand { margin-top: 17px; font-size: 11px; padding: 7px 10px; background: rgba(255,99,60,.08); border-color: rgba(255,145,111,.4); color: #ffc0ac; }
  .diagram-panel-footer { padding: 12px 18px; flex-wrap: wrap; gap: 10px; }
  .diagram-credit { width: 100%; font-size: 9px; }
  .diagram-hint { display: block; }
  .diagram-pagination { gap: 9px; }
  .diagram-pagination button { width: 28px; height: 26px; }
  .diagram-pagination > span { font-size: 9px; letter-spacing: .03em; }
  .methodology-note { font-size: 10px; margin-top: 16px; }
  .workflow { margin-top: 30px; }
  .workflow-route { grid-template-columns: repeat(2,minmax(0,1fr)); gap: 23px 15px; padding-bottom: 25px; }
  .workflow-route > li:not(:last-child)::after { display: none; }
  .workflow-node { flex-basis: 39px; height: 39px; font-size: 10px; }
  .workflow-step strong { font-size: 18px; background: transparent; }
  .workflow-step small { font-size: 10px; }
  .workflow-panel { grid-template-columns: 1fr; padding: 27px 25px; gap: 29px; }
  .workflow-panel-main h3 { font-size: 23px; }
  .workflow-panel-main > p:last-child, .workflow-evidence dd { font-size: 12px; }
  .workflow-evidence { gap: 19px; }
  .workflow-evidence > div { padding-left: 16px; }
  .workflow-loop { font-size: 10px; line-height: 1.9; }
  .diagram-dialog { width: calc(100vw - 16px); height: calc(100dvh - 20px); border-radius: 7px; }
  .diagram-dialog-toolbar { padding: 14px; gap: 10px; flex-wrap: wrap; }
  .diagram-dialog-toolbar > div:first-child { max-width: calc(100% - 48px); }
  .diagram-dialog-toolbar h2 { font-size: 16px; }
  .diagram-dialog-toolbar p { font-size: 9px; }
  .diagram-zoom-controls { order: 3; margin: 0; width: 100%; gap: 10px; }
  .diagram-close { margin-left: auto; }
  .diagram-zoom-controls button { height: 31px; }
  .diagram-dialog-footer { padding: 11px 14px; flex-direction: column; gap: 5px; font-size: 9px; }
}