:root {
  --fog: #e8e8e8;
  --ink: #2f3238;
  --quiet: #5f646e;
  --line: #d4d4d4;
  --accent: #4a5568;
  --accent-deep: #343b48;
  --shade: #c3c3c3;
  --glow: #ffffff;
  --focus: #3d4a62;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--fog);
  line-height: 1.7;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--accent-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--ink);
}

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.jump {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--fog);
  padding: 0.6rem 1rem;
  z-index: 20;
}

.jump:focus {
  left: 1rem;
  top: 1rem;
}

.shell {
  width: min(1180px, calc(100% - 2.4rem));
  margin-inline: auto;
}

.mast {
  position: sticky;
  top: 0;
  z-index: 8;
  background: color-mix(in srgb, var(--fog) 88%, transparent);
  backdrop-filter: blur(10px);
}

.mast-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.9rem 0;
}

.mark {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: inherit;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.mark img {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: 8px 8px 16px var(--shade), -6px -6px 14px var(--glow);
}

.menu-btn {
  display: none;
  border: 0;
  background: var(--fog);
  color: var(--ink);
  padding: 0.55rem 1rem;
  border-radius: 999px;
  font: inherit;
  cursor: pointer;
  box-shadow: 8px 8px 16px var(--shade), -6px -6px 14px var(--glow);
}

.menu-btn[aria-expanded="true"] {
  box-shadow: inset 5px 5px 10px var(--shade), inset -4px -4px 8px var(--glow);
}

.trail {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 1.15rem;
}

.trail a {
  text-decoration: none;
  color: var(--quiet);
  font-weight: 600;
  padding: 0.25rem 0;
}

.trail a:hover,
.trail a[aria-current="page"] {
  color: var(--ink);
}

.hero-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 7rem;
  align-items: center;
  padding: 4.5rem 0 3.2rem;
}

.pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin: 0 0 1.2rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.95rem;
  border-radius: 999px;
  background: var(--fog);
  color: var(--quiet);
  font-size: 0.88rem;
  font-weight: 600;
  box-shadow: 7px 7px 14px var(--shade), -5px -5px 12px var(--glow);
}

h1,
h2,
h3 {
  line-height: 1.25;
  margin: 0 0 0.8rem;
}

h1 {
  font-size: clamp(2rem, 4vw, 3.15rem);
  letter-spacing: -0.03em;
}

h2 {
  font-size: clamp(1.4rem, 2.4vw, 1.85rem);
}

.lead {
  margin: 0 0 1.6rem;
  color: var(--quiet);
  font-size: 1.05rem;
}

.action-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
}

.puff,
.quiet-puff {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.7rem 1.4rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  border: 0;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
}

.puff {
  color: #f4f4f4;
  background: var(--accent);
  box-shadow: 12px 12px 22px var(--shade), -8px -8px 18px var(--glow);
}

.puff:hover {
  color: #fff;
  background: var(--accent-deep);
}

.quiet-puff {
  color: var(--ink);
  background: var(--fog);
  box-shadow: 10px 10px 20px var(--shade), -8px -8px 16px var(--glow);
}

.puff:active,
.quiet-puff:active {
  box-shadow: inset 6px 6px 12px var(--shade), inset -4px -4px 10px var(--glow);
}

.hero-visual {
  margin: 0;
  padding: 1.2rem;
  border-radius: 36px;
  background: var(--fog);
  box-shadow: 22px 22px 40px var(--shade), -16px -16px 34px var(--glow);
}

.hero-visual img {
  display: block;
  width: 100%;
  border-radius: 26px;
}

.metric-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.4rem;
  margin: 0.4rem 0 3.4rem;
}

.metric {
  padding: 1.3rem 1.2rem;
  border-radius: 28px;
  background: var(--fog);
  box-shadow: 14px 14px 26px var(--shade), -10px -10px 22px var(--glow);
}

.metric strong {
  display: block;
  font-size: 1.35rem;
}

.metric span {
  color: var(--quiet);
  font-size: 0.92rem;
}

.block {
  padding: 0.4rem 0 3.6rem;
}

.gate-grid,
.card-grid,
.os-grid,
.pair {
  display: grid;
  gap: 1.4rem;
}

.gate-grid,
.card-grid,
.os-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.pair {
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
}

.cushion {
  padding: 1.4rem 1.3rem;
  border-radius: 28px;
  background: var(--fog);
  box-shadow: 16px 16px 30px var(--shade), -12px -12px 24px var(--glow);
}

.cushion p:last-child,
.cushion ol:last-child,
.cushion ul:last-child {
  margin-bottom: 0;
}

.gate-grid a,
.card-grid article,
.os-grid article {
  text-decoration: none;
  color: inherit;
}

.circle {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  margin-bottom: 1rem;
  background: var(--fog);
  box-shadow: 10px 10px 18px var(--shade), -7px -7px 16px var(--glow);
}

.ico {
  width: 22px;
  height: 22px;
  border: 2.4px solid var(--accent);
  border-radius: 50%;
  position: relative;
}

.ico.core {
  border-radius: 6px;
}

.ico.yaml {
  border-radius: 4px 4px 10px 10px;
}

.ico.theme::after {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  position: absolute;
}

.ico.guard {
  border-radius: 50% 50% 8px 8px;
}

.ico.tun {
  width: 18px;
  height: 10px;
  border-radius: 999px;
}

.ico.rule {
  width: 18px;
  height: 18px;
  border-radius: 3px;
}

.ico.win,
.ico.mac,
.ico.lin,
.ico.and {
  border-style: solid;
}

.note {
  color: var(--quiet);
  margin: 0 0 1rem;
}

ol,
ul {
  padding-left: 1.15rem;
}

.faq-list {
  display: grid;
  gap: 1rem;
}

.faq-list details {
  border-radius: 24px;
  background: var(--fog);
  box-shadow: 12px 12px 22px var(--shade), -9px -9px 18px var(--glow);
  padding: 0.2rem 0.4rem;
}

.faq-list summary {
  cursor: pointer;
  font-weight: 700;
  padding: 0.95rem 1rem;
  list-style: none;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list details p {
  margin: 0;
  padding: 0 1rem 1rem;
  color: var(--quiet);
}

.foot {
  padding: 2.6rem 0 2rem;
  margin-top: 1rem;
}

.foot-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.5rem;
  padding: 1.6rem;
  border-radius: 32px;
  background: var(--fog);
  box-shadow: 18px 18px 34px var(--shade), -14px -14px 28px var(--glow);
}

.foot h3 {
  font-size: 0.95rem;
}

.foot a,
.foot p {
  display: block;
  margin: 0.35rem 0;
  color: var(--quiet);
  text-decoration: none;
}

.legal {
  color: var(--quiet);
  font-size: 0.88rem;
  text-align: center;
  margin: 1.4rem 0 0;
}

.anchor-box {
  margin: 0 0 2.4rem;
}

@media (max-width: 980px) {
  .hero-split,
  .pair,
  .gate-grid,
  .card-grid,
  .os-grid,
  .metric-row,
  .foot-grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.3rem;
  }

  .hero-split {
    gap: 2.2rem;
    padding-top: 2.4rem;
  }
}

@media (max-width: 720px) {
  .menu-btn {
    display: inline-flex;
  }

  .trail {
    display: none;
    position: absolute;
    right: 1.2rem;
    top: 4.3rem;
    flex-direction: column;
    padding: 1rem 1.1rem;
    border-radius: 22px;
    background: var(--fog);
    box-shadow: 14px 14px 28px var(--shade), -10px -10px 20px var(--glow);
  }

  .trail.is-open {
    display: flex;
  }

  .hero-split,
  .pair,
  .gate-grid,
  .card-grid,
  .os-grid,
  .metric-row,
  .foot-grid {
    grid-template-columns: 1fr;
  }
}

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

  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}