:root {
  --fluid-yellow: #F2C14E;
  --fluid-vermilion: #E25B45;
  --fluid-teal: #2A9D8F;
  --grid-black: #1A1A1A;
  --paper: #F7F4EC;
  --paper-soft: #EFECE2;
  --mute: #524F49;
  --max: 1200px;
  --pill: 999px;
  --font: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --mono: "Consolas", "Courier New", monospace;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--grid-black);
  background-color: var(--paper);
  background-image:
    linear-gradient(90deg, rgba(26, 26, 26, 0.14) 1px, transparent 1px),
    linear-gradient(180deg, rgba(26, 26, 26, 0.14) 1px, transparent 1px);
  background-size: 96px 96px;
  line-height: 1.72;
  font-size: 16px;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: 0; background: none; }

.container {
  width: min(100% - 64px, var(--max));
  margin-inline: auto;
}

.skip { position: absolute; left: -999px; }
.skip:focus {
  left: 16px;
  top: 16px;
  z-index: 100;
  background: var(--grid-black);
  color: var(--fluid-yellow);
  padding: 8px 12px;
}

/* fixed 64px white semi-transparent top bar */
.header {
  position: fixed;
  inset: 0 0 auto;
  height: 64px;
  z-index: 50;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border-bottom: 2px solid var(--grid-black);
  contain: layout paint style;
}

.nav {
  height: 64px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  width: min(100% - 48px, var(--max));
  margin-inline: auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  justify-self: start;
}

.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 4px;
  overflow: hidden;
  background: var(--fluid-yellow);
  border: 2px solid var(--grid-black);
  flex-shrink: 0;
}
.brand-mark img { width: 100%; height: 100%; object-fit: cover; }

.brand-name {
  font-size: 15px;
  font-weight: 900;
  color: var(--grid-black);
  letter-spacing: 0.03em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  justify-self: center;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a { font-size: 14px; color: var(--mute); font-weight: 600; }
.nav-links a:hover,
.nav-links a.is-active {
  color: var(--grid-black);
  font-weight: 900;
  border-bottom: 2px solid var(--fluid-vermilion);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  justify-self: end;
}

.btn-ghost {
  font-size: 14px;
  font-weight: 700;
  color: var(--grid-black);
  padding: 8px 12px;
}

.btn-solid {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 22px;
  border-radius: var(--pill);
  background: var(--grid-black);
  color: #FFFFFF;
  font-size: 14px;
  font-weight: 800;
  border: 2px solid var(--grid-black);
  box-shadow: 3px 3px 0 var(--fluid-yellow);
}
.btn-solid:hover {
  background: var(--fluid-vermilion);
  color: #FFFFFF;
}

.btn-solid.lg {
  min-height: 48px;
  padding: 0 32px;
  font-size: 16px;
}

.menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: 4px;
  border: 2px solid var(--grid-black);
  align-items: center;
  justify-content: center;
  color: var(--grid-black);
  justify-self: end;
}
.menu-btn span,
.menu-btn span::before,
.menu-btn span::after {
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
  position: relative;
}
.menu-btn span::before,
.menu-btn span::after { content: ""; position: absolute; left: 0; }
.menu-btn span::before { top: -5px; }
.menu-btn span::after { top: 5px; }

.drawer {
  display: none;
  position: fixed;
  inset: 64px 0 auto;
  background: var(--paper);
  border-bottom: 2px solid var(--grid-black);
  padding: 12px 24px 20px;
  z-index: 49;
}
.drawer.is-open { display: block; }
.drawer a {
  display: block;
  padding: 12px 0;
  border-bottom: 1px solid var(--grid-black);
  color: var(--grid-black);
  font-size: 15px;
  font-weight: 700;
}

/* Fluid Grid Skeleton (Highest Priority):
   - Background is a pool of flat-colored fluid sliced by a sharp #1A1A1A grid.
   - Fluid consists of 3 flat color puddles: #F2C14E (ochre yellow), #E25B45 (vermilion), #2A9D8F (verdigris teal).
   - Keywords sit strictly on the 4 grid intersections (Nodes 1-4), and WorkBuddy网页版 sits outside the grid frame. */
.fluid-grid-stage {
  position: relative;
  max-width: 980px;
  margin: 0 auto 38px;
  padding-bottom: 34px;
}

.fluid-grid-board {
  position: relative;
  border: 3px solid var(--grid-black);
  background-color: var(--paper);
  overflow: hidden;
  box-shadow: 10px 10px 0 var(--grid-black);
}

/* Three flat-coated fluid shapes (#F2C14E, #E25B45, #2A9D8F) — strictly flat fills, no gradients */
.fluid-pool-svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

/* Crisp #1A1A1A grid slicing across the fluid pool */
.sliced-grid {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  grid-template-rows: repeat(2, minmax(148px, auto));
  background-image:
    linear-gradient(90deg, rgba(26, 26, 26, 0.25) 1px, transparent 1px),
    linear-gradient(180deg, rgba(26, 26, 26, 0.25) 1px, transparent 1px);
  background-size: 48px 48px;
}

.grid-quadrant {
  position: relative;
  padding: 34px 28px;
  border-right: 2px solid var(--grid-black);
  border-bottom: 2px solid var(--grid-black);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}
.grid-quadrant:nth-child(2n) { border-right: 0; }
.grid-quadrant:nth-child(n+3) { border-bottom: 0; }

/* Crosshair pin at the exact intersection point */
.intersection-pin {
  position: relative;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 12px 22px;
  background: #FFFFFF;
  border: 2.5px solid var(--grid-black);
  box-shadow: 5px 5px 0 var(--grid-black);
}
.intersection-pin::before,
.intersection-pin::after {
  content: "";
  position: absolute;
  background: var(--grid-black);
}
.intersection-pin::before {
  width: 14px;
  height: 2px;
  top: -8px;
  left: -8px;
}
.intersection-pin::after {
  width: 2px;
  height: 14px;
  top: -14px;
  left: -2px;
}

.node-coord {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--grid-black);
  background: var(--fluid-yellow);
  padding: 1px 7px;
  border: 1px solid var(--grid-black);
}
.grid-quadrant:nth-child(2) .node-coord { background: var(--fluid-vermilion); color: #fff; }
.grid-quadrant:nth-child(3) .node-coord { background: var(--fluid-teal); color: #fff; }
.grid-quadrant:nth-child(4) .node-coord { background: var(--fluid-yellow); color: var(--grid-black); }

.intersection-pin h1,
.intersection-pin .node-word {
  margin: 0;
  font-size: clamp(22px, 3vw, 34px);
  font-weight: 900;
  color: var(--grid-black);
  letter-spacing: 0.02em;
  line-height: 1.15;
}

/* Outside the grid (网格外 WorkBuddy网页版) */
.outside-grid-tag {
  position: absolute;
  right: 0;
  bottom: -10px;
  z-index: 4;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 18px;
  background: var(--fluid-teal);
  color: #FFFFFF;
  border: 2.5px solid var(--grid-black);
  box-shadow: 4px 4px 0 var(--grid-black);
  font-size: 14px;
  font-weight: 900;
  transform: rotate(-2deg);
}
.outside-grid-tag small {
  font-family: var(--mono);
  font-size: 11px;
  background: var(--grid-black);
  color: var(--fluid-yellow);
  padding: 2px 6px;
}

/* hero */
.hero {
  padding: 140px 0 72px;
  text-align: center;
}

.hero-lead {
  margin: 0 auto 22px;
  max-width: 560px;
  color: var(--grid-black);
  font-size: 16px;
  font-weight: 500;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  margin-bottom: 36px;
}

.hero-link {
  color: var(--fluid-vermilion);
  font-size: 14px;
  font-weight: 900;
  border-bottom: 2px solid var(--fluid-vermilion);
}

.hero-shot-wrap {
  position: relative;
  max-width: 1000px;
  margin: 0 auto;
}

.hero-glow {
  position: absolute;
  left: 50%;
  top: 46%;
  width: 78%;
  height: 72%;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(242, 193, 78, 0.38), rgba(42, 157, 143, 0.22) 52%, transparent 72%);
  filter: none;
  contain: paint;
  pointer-events: none;
}

.hero-shot {
  position: relative;
  border-radius: 12px;
  overflow: hidden;
  padding: 12px;
  background: #FFFFFF;
  border: 3px solid var(--grid-black);
  box-shadow: 8px 8px 0 var(--grid-black);
}
.hero-shot img { width: 100%; border-radius: 6px; }

/* sections */
.section {
  padding: 96px 0;
  content-visibility: auto;
  contain-intrinsic-size: auto 720px;
}

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 40px;
  margin-bottom: 28px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 28px;
  padding: 0 14px;
  border-radius: var(--pill);
  background: var(--fluid-yellow);
  border: 2px solid var(--grid-black);
  color: var(--grid-black);
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.section-title {
  margin: 12px 0 0;
  font-size: clamp(30px, 4vw, 46px);
  font-weight: 900;
  line-height: 1.2;
  color: var(--grid-black);
}

.section-sub {
  max-width: 400px;
  margin: 0;
  color: var(--mute);
  font-size: 15px;
}

.center-copy {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 32px;
}
.center-copy p { color: var(--mute); }

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 6px;
  border-radius: var(--pill);
  background: var(--fluid-teal);
  border: 2px solid var(--grid-black);
  width: fit-content;
  margin-bottom: 18px;
}

.tab {
  border-radius: var(--pill);
  padding: 9px 18px;
  font-size: 14px;
  font-weight: 700;
  color: #FFFFFF;
}
.tab.is-on {
  background: #FFFFFF;
  color: var(--grid-black);
  font-weight: 900;
  border: 1.5px solid var(--grid-black);
}

.scenario-card {
  display: grid;
  grid-template-columns: 30% 70%;
  min-height: 410px;
  border-radius: 16px;
  overflow: hidden;
  background: #FFFFFF;
  border: 3px solid var(--grid-black);
  box-shadow: 8px 8px 0 var(--grid-black);
}

.scenario-text {
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 14px;
  border-right: 2px solid var(--grid-black);
  background: var(--fluid-yellow);
}
.scenario-text h3 {
  margin: 0;
  font-size: 24px;
  font-weight: 900;
  color: var(--grid-black);
}
.scenario-text p {
  margin: 0;
  color: var(--grid-black);
  font-size: 14px;
}

.scenario-visual {
  background: var(--paper);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 22px;
}
.scenario-visual img {
  width: 100%;
  border-radius: 8px;
  border: 2px solid var(--grid-black);
}

.pane { display: none; }
.pane.is-on { display: contents; }

/* cooperation: light gray full band */
.eco {
  background: #ECEAE3;
  border-top: 2px solid var(--grid-black);
  border-bottom: 2px solid var(--grid-black);
  content-visibility: auto;
  contain-intrinsic-size: auto 480px;
}

.logo-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
}

.logo-chip {
  min-width: 118px;
  padding: 14px 18px;
  border-radius: 6px;
  background: #FFFFFF;
  border: 2px solid var(--grid-black);
  box-shadow: 3px 3px 0 var(--grid-black);
  text-align: center;
  font-size: 14px;
  font-weight: 900;
  color: var(--grid-black);
}
.logo-chip:nth-child(3n+1) { background: var(--fluid-yellow); }
.logo-chip:nth-child(3n+2) { background: var(--fluid-vermilion); color: #fff; }
.logo-chip:nth-child(3n) { background: var(--fluid-teal); color: #fff; }

/* trust: light rounded band + 3 white cards */
.trust-band {
  background: var(--paper-soft);
  border: 3px solid var(--grid-black);
  border-radius: 20px;
  padding: 46px 36px;
  box-shadow: 8px 8px 0 var(--grid-black);
}

.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 26px;
}

.trust-card {
  background: #FFFFFF;
  color: var(--grid-black);
  border-radius: 12px;
  padding: 28px;
  border: 2px solid var(--grid-black);
}
.trust-card h3 {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 900;
  color: var(--grid-black);
}
.trust-card p {
  margin: 0;
  color: var(--mute);
  font-size: 14px;
}

/* download */
.dl-groups {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 44px;
  margin-top: 32px;
}

.dl-group-label {
  display: block;
  margin-bottom: 14px;
  color: var(--grid-black);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.dl-tiles {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.dl-tile {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px;
  border-radius: 8px;
  background: #FFFFFF;
  border: 2px solid var(--grid-black);
  box-shadow: 4px 4px 0 var(--grid-black);
  position: relative;
}

.dl-ico {
  width: 38px;
  height: 38px;
  border-radius: 4px;
  background: var(--fluid-teal);
  color: #FFFFFF;
  border: 1.5px solid var(--grid-black);
  display: grid;
  place-items: center;
  font-size: 11px;
  font-weight: 900;
  flex-shrink: 0;
}

.dl-tile strong {
  display: block;
  font-size: 14px;
  font-weight: 900;
  color: var(--grid-black);
}
.dl-tile span {
  font-size: 12px;
  color: var(--mute);
}

.badge {
  position: absolute;
  top: 8px;
  right: 10px;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: var(--pill);
  background: var(--fluid-vermilion);
  color: #FFFFFF;
  border: 1px solid var(--grid-black);
  font-weight: 800;
}

/* subpages */
.page-hero {
  padding: 124px 0 48px;
  text-align: center;
}

.page-body {
  padding: 48px 0 88px;
  content-visibility: auto;
  contain-intrinsic-size: auto 680px;
}

.article {
  max-width: 760px;
  background: #FFFFFF;
  border: 3px solid var(--grid-black);
  border-radius: 12px;
  padding: 36px;
  box-shadow: 6px 6px 0 var(--grid-black);
}
.article h2 {
  margin: 28px 0 10px;
  font-size: 24px;
  font-weight: 900;
  color: var(--grid-black);
}
.article h2:first-child { margin-top: 0; }
.article p { color: var(--mute); margin: 0 0 12px; }
.article ul { color: var(--mute); padding-left: 1.2em; }
.article li { margin-bottom: 8px; }
.article a { color: var(--fluid-vermilion); font-weight: 800; border-bottom: 2px solid var(--fluid-vermilion); }

.help-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-bottom: 28px;
}

.help-card {
  padding: 24px;
  border-radius: 10px;
  background: #FFFFFF;
  border: 2px solid var(--grid-black);
  box-shadow: 4px 4px 0 var(--grid-black);
}
.help-card h3 {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 900;
  color: var(--grid-black);
}
.help-card p {
  margin: 0;
  color: var(--mute);
  font-size: 14px;
}

.entry-box {
  max-width: 620px;
  margin: 0 auto 36px;
  padding: 32px;
  border-radius: 12px;
  background: #FFFFFF;
  border: 3px solid var(--grid-black);
  box-shadow: 6px 6px 0 var(--grid-black);
  text-align: center;
}
.entry-box p { color: var(--mute); margin: 0 0 18px; }
.entry-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}
.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: var(--pill);
  border: 2px solid var(--grid-black);
  background: var(--fluid-yellow);
  color: var(--grid-black);
  font-size: 14px;
  font-weight: 800;
}

/* footer: dark */
.footer {
  content-visibility: auto;
  contain-intrinsic-size: auto 520px;
  background: var(--grid-black);
  color: rgba(247, 244, 236, 0.84);
  padding: 56px 0 0;
  border-top: 3px solid var(--grid-black);
}

.footer-top {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid rgba(247, 244, 236, 0.18);
}

.footer-brand { max-width: 320px; }
.footer-brand .brand-name { color: var(--fluid-yellow); }
.footer-brand p {
  margin: 12px 0 0;
  font-size: 13px;
  color: rgba(247, 244, 236, 0.72);
  line-height: 1.7;
}

.footer-cols {
  display: flex;
  gap: 72px;
}

.footer-col h3 {
  margin: 0 0 12px;
  font-size: 13px;
  color: var(--fluid-yellow);
  font-weight: 800;
}

.footer-col a {
  display: block;
  font-size: 13px;
  color: rgba(247, 244, 236, 0.72);
  margin-bottom: 9px;
}
.footer-col a:hover { color: #FFFFFF; }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 22px 0;
  font-size: 12px;
  color: rgba(247, 244, 236, 0.55);
}

.footer-wordmark {
  text-align: center;
  padding: 20px 0 36px;
  font-size: clamp(44px, 9.5vw, 112px);
  font-weight: 900;
  letter-spacing: -0.03em;
  color: rgba(242, 193, 78, 0.12);
  line-height: 1;
  user-select: none;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

@media (max-width: 968px) {
  .nav-links,
  .nav-actions { display: none; }
  .menu-btn { display: inline-flex; }
  .nav { grid-template-columns: 1fr auto; }
  .section-head {
    flex-direction: column;
    align-items: flex-start;
  }
  .sliced-grid,
  .scenario-card,
  .trust-grid,
  .dl-groups,
  .help-grid { grid-template-columns: 1fr; }
  .grid-quadrant { border-right: 0 !important; border-bottom: 2px solid var(--grid-black) !important; }
  .grid-quadrant:last-child { border-bottom: 0 !important; }
  .scenario-text { border-right: 0; border-bottom: 2px solid var(--grid-black); }
  .footer-top,
  .footer-bottom { flex-direction: column; }
  .footer-cols { flex-wrap: wrap; gap: 28px; }
  .container { width: min(100% - 32px, var(--max)); }
}

@media (max-width: 640px) {
  .container { width: min(100% - 16px, var(--max)); }
  .dl-tiles { grid-template-columns: 1fr; }
  .hero { padding-top: 112px; }
  .section { padding: 72px 0; }
  .trust-band { padding: 28px 18px; }
  .article { padding: 24px 18px; }
  .header,
  .drawer {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}