:root {
  --dark: #20262a;
  --panel: #1f2529;
  --panel-soft: #252c31;
  --white: #ffffff;
  --muted: rgba(255, 255, 255, 0.78);
  --line: rgba(255, 255, 255, 0.78);
  --green: #149763;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--white);
  background: #d7d9dc;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", Arial, sans-serif;
  line-height: 1.55;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: #202528;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06);
}

.nav-wrap {
  width: min(1120px, calc(100% - 32px));
  min-height: 80px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 34px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
}

.brand img {
  width: 52px;
  height: 52px;
  object-fit: contain;
  border-radius: 0;
}

.brand span {
  color: #21a66f;
  white-space: nowrap;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.site-nav a {
  font-size: 16px;
  font-weight: 700;
  color: #fff;
}

.site-nav a::before {
  content: "";
  width: 14px;
  height: 14px;
  display: inline-block;
  margin-right: 8px;
  vertical-align: -2px;
  border: 2px solid #fff;
  border-radius: 50%;
}

.site-nav a:nth-child(2)::before {
  border-radius: 2px;
}

.site-nav a:nth-child(3)::before {
  content: "?";
  width: 15px;
  height: 15px;
  color: #202528;
  background: #fff;
  border: 0;
  text-align: center;
  line-height: 15px;
  font-size: 12px;
  font-weight: 900;
}

.auth-actions {
  display: flex;
  gap: 12px;
  align-items: center;
}

.signup,
.login {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 38px;
  padding: 0 15px;
  border-radius: 6px;
  font-size: 16px;
  font-weight: 700;
}

.signup {
  background: var(--green);
  color: #fff;
}

.login {
  border: 1px solid #fff;
  color: #fff;
}

.page-shell {
  position: relative;
  min-height: calc(100vh - 80px);
}

.hero-screen {
  position: relative;
  min-height: 700px;
  overflow: hidden;
}

.hero-bg,
.hero-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-bg {
  object-fit: cover;
  filter: grayscale(100%) brightness(1.06) contrast(0.92);
}

.hero-overlay {
  background:
    linear-gradient(180deg, rgba(32, 37, 40, 0.08) 0%, rgba(32, 37, 40, 0.16) 52%, rgba(32, 37, 40, 0.28) 100%),
    rgba(235, 237, 240, 0.08);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 50px 0 70px;
  text-align: center;
}

.hero-content h1 {
  margin: 0;
  color: #fff;
  font-size: clamp(42px, 5vw, 62px);
  font-weight: 300;
  line-height: 1.12;
  -webkit-text-stroke: 1px rgba(31, 37, 41, 0.68);
  paint-order: stroke fill;
  text-shadow:
    0 2px 0 rgba(31, 37, 41, 0.5),
    0 8px 24px rgba(31, 37, 41, 0.45);
}

.hero-content > p {
  margin: 12px 0 46px;
  color: rgba(255, 255, 255, 0.94);
  font-size: 19px;
  font-weight: 700;
  -webkit-text-stroke: 0.45px rgba(31, 37, 41, 0.72);
  paint-order: stroke fill;
  text-shadow:
    0 1px 0 rgba(31, 37, 41, 0.7),
    0 5px 16px rgba(31, 37, 41, 0.42);
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px 24px;
  align-items: stretch;
  min-width: 0;
}

.quick-grid article,
.tool-grid article {
  min-width: 0;
  min-height: 124px;
  padding: 18px 20px;
  border-radius: 5px;
  background: rgba(31, 37, 41, 0.98);
  color: #fff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.18);
  display: flex;
  flex-direction: column;
  justify-content: center;
  text-align: center;
}

.quick-grid h2,
.tool-grid h3 {
  margin: 0 0 8px;
  font-size: 28px;
  line-height: 1.2;
  font-weight: 800;
  overflow-wrap: anywhere;
}

.quick-grid p,
.tool-grid p {
  margin: 0;
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.feature-panel {
  position: relative;
  z-index: 2;
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto 46px;
  padding: 36px 30px 38px;
  border-radius: 5px;
  background: rgba(31, 37, 41, 0.98);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.22);
  text-align: center;
}

.panel-head {
  max-width: 760px;
  margin: 0 auto 28px;
}

.panel-head h2 {
  margin: 0;
  color: #fff;
  font-size: 30px;
  line-height: 1.25;
}

.panel-head p {
  margin: 10px 0 0;
  color: #fff;
  font-size: 15px;
  font-weight: 700;
}

.tool-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px 24px;
  min-width: 0;
}

.tool-grid article {
  min-height: 176px;
  padding: 24px 22px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, 0.82);
  background: #21272b;
  box-shadow: none;
}

.tool-grid .ai-card {
  grid-column: 2;
  min-height: 150px;
  background:
    linear-gradient(135deg, rgba(20, 151, 99, 0.18), rgba(255, 255, 255, 0.03)),
    #21272b;
}

.icon {
  width: 34px;
  height: 34px;
  margin-bottom: 8px;
  display: grid;
  place-items: center;
  color: #fff;
  border: 2px solid #fff;
  border-radius: 5px;
  font-size: 17px;
  font-weight: 900;
}

.grid-icon {
  border: 0;
  background:
    linear-gradient(#fff, #fff) 0 0 / 8px 8px,
    linear-gradient(#fff, #fff) 13px 0 / 8px 8px,
    linear-gradient(#fff, #fff) 26px 0 / 8px 8px,
    linear-gradient(#fff, #fff) 0 13px / 8px 8px,
    linear-gradient(#fff, #fff) 13px 13px / 8px 8px,
    linear-gradient(#fff, #fff) 26px 13px / 8px 8px,
    linear-gradient(#fff, #fff) 0 26px / 8px 8px,
    linear-gradient(#fff, #fff) 13px 26px / 8px 8px,
    linear-gradient(#fff, #fff) 26px 26px / 8px 8px;
  background-repeat: no-repeat;
}

.columns-icon,
.doc-icon,
.ruler-icon,
.chip-icon {
  position: relative;
}

.columns-icon::before {
  content: "";
  position: absolute;
  inset: 4px;
  border-left: 5px solid #fff;
  border-right: 5px solid #fff;
  box-shadow: 10px 0 0 #fff;
}

.doc-icon::before {
  content: "";
  position: absolute;
  inset: 4px 7px;
  border: 2px solid #fff;
  border-top-width: 5px;
}

.ruler-icon::before {
  content: "";
  position: absolute;
  width: 20px;
  height: 24px;
  border-left: 5px solid #fff;
  border-bottom: 3px solid #fff;
}

.chip-icon::before {
  content: "";
  position: absolute;
  inset: 8px;
  border: 3px solid #fff;
  border-radius: 4px;
  box-shadow:
    -9px 0 0 -6px #fff,
    9px 0 0 -6px #fff,
    0 -9px 0 -6px #fff,
    0 9px 0 -6px #fff;
}

.site-footer {
  position: relative;
  z-index: 2;
  padding: 24px max(16px, calc((100% - 1120px) / 2)) 28px;
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(260px, 1.1fr) minmax(360px, 1.35fr);
  align-items: center;
  gap: 28px;
  color: rgba(255, 255, 255, 0.82);
  background: #202528;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.site-footer strong,
.site-footer span {
  display: block;
}

.site-footer strong {
  color: #fff;
  font-size: 16px;
}

.footer-note {
  color: rgba(255, 255, 255, 0.72);
  font-size: 14px;
  line-height: 1.7;
}

.footer-records {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  justify-content: flex-end;
  font-size: 13px;
}

@media (max-width: 900px) {
  .nav-wrap {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 12px 0;
  }

  .site-nav,
  .auth-actions {
    justify-content: center;
    flex-wrap: wrap;
  }

  .site-nav {
    width: 100%;
    gap: 12px 20px;
  }

  .site-nav a {
    font-size: 15px;
    white-space: nowrap;
  }

  .quick-grid,
  .tool-grid {
    grid-template-columns: 1fr;
  }

  .tool-grid .ai-card {
    grid-column: auto;
  }

  .site-footer {
    grid-template-columns: 1fr;
    align-items: center;
    text-align: center;
  }

  .footer-records {
    justify-content: center;
  }
}

@media (max-width: 560px) {
  .nav-wrap {
    width: min(100% - 28px, 390px);
  }

  .brand {
    justify-content: center;
  }

  .brand img {
    width: 46px;
    height: 46px;
  }

  .hero-screen {
    min-height: 0;
  }

  .hero-content {
    width: min(100% - 48px, 320px);
    padding: 46px 0 44px;
  }

  .hero-content h1 {
    max-width: 100%;
    font-size: 31px;
    line-height: 1.18;
  }

  .hero-content > p {
    max-width: 292px;
    margin: 12px auto 34px;
    font-size: 15px;
    line-height: 1.58;
    overflow-wrap: anywhere;
  }

  .quick-grid {
    width: min(100%, 280px);
    margin-left: auto;
    margin-right: auto;
    gap: 16px;
  }

  .quick-grid article {
    width: 100%;
    max-width: 100%;
    padding: 20px 18px;
  }

  .quick-grid h2,
  .tool-grid h3 {
    font-size: 24px;
  }

  .quick-grid p,
  .tool-grid p {
    max-width: 244px;
    margin-left: auto;
    margin-right: auto;
    font-size: 13px;
    line-height: 1.65;
  }

  .quick-grid article,
  .tool-grid article {
    min-height: auto;
  }

  .feature-panel {
    width: min(100% - 48px, 300px);
    margin-bottom: 28px;
    padding: 28px 18px 30px;
  }

  .panel-head h2 {
    font-size: 25px;
  }

  .panel-head p {
    font-size: 14px;
    line-height: 1.65;
  }

  .tool-grid {
    width: min(100%, 252px);
    margin-left: auto;
    margin-right: auto;
    gap: 16px;
  }

  .tool-grid article {
    width: 100%;
    max-width: 100%;
    padding: 22px 16px;
  }

  .site-footer {
    padding-top: 24px;
    padding-bottom: 26px;
  }
}