* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  background: var(--ff-bg);
  color: var(--ff-text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

.top,
.page,
.foot {
  width: 100%;
  max-width: 1128px;
  margin: 0 auto;
  padding-inline: 24px;
}

.page {
  flex: 1;
}

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 700;
  text-decoration: none;
}

.brand img {
  display: block;
  width: 32px;
  height: 32px;
}

.switches {
  display: flex;
  gap: 8px;
}

/* Both switches need JS; without it the privacy pages simply show both languages. */
:root:not([data-lang]) .switches {
  display: none;
}

.pill {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  padding: 0;
  border: 1px solid var(--ff-border);
  border-radius: 999px;
  background: transparent;
  color: var(--ff-muted);
  font: inherit;
  font-size: 13px;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.pill:hover {
  color: var(--ff-text);
  border-color: var(--ff-muted);
}

.pill svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
}

.pill .sun,
:root[data-theme="dark"] .pill .moon {
  display: none;
}

:root[data-theme="dark"] .pill .sun {
  display: block;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .pill .moon {
    display: none;
  }

  :root:not([data-theme="light"]) .pill .sun {
    display: block;
  }
}

:focus-visible {
  outline: 2px solid var(--ff-focus);
  outline-offset: 2px;
}

.foot {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 24px;
  padding-block: 32px;
  color: var(--ff-subtle);
  font-size: 13px;
}

.foot nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 20px;
}

.foot a {
  text-decoration: none;
}

.foot a:hover {
  color: var(--ff-text);
}

/* Home */
.hero {
  padding-block: clamp(24px, 6vh, 56px) clamp(28px, 5vh, 44px);
  text-align: center;
}

.hero h1 {
  margin: 0;
  font-size: clamp(36px, 6.4vw, 68px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.03em;
}

.hero .accent {
  color: var(--ff-accent);
}

:root[data-lang="en"] .hero .accent {
  display: block;
}

.hero p {
  margin: 14px 0 0;
  color: var(--ff-muted);
  font-size: clamp(16px, 2vw, 19px);
  text-wrap: balance;
}

.cta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 28px;
}

.cta > * {
  display: grid;
  place-items: center;
  height: 46px;
  padding: 0 22px;
  border: 1px solid var(--ff-border);
  border-radius: 12px;
  background: var(--ff-surface);
  color: var(--ff-text);
  font: inherit;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.15s;
}

.cta a:hover {
  background: var(--ff-hover);
}

.cta a.main {
  border-color: var(--ff-accent-edge);
  background: var(--ff-accent);
  color: var(--ff-on-accent);
}

.cta a.main:hover {
  background: var(--ff-accent-hover);
}

.cta button:disabled {
  background: transparent;
  color: var(--ff-subtle);
  cursor: default;
  opacity: 0.6;
}

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 32px 0 24px;
  padding: 0;
  list-style: none;
}

.features li {
  padding: 24px;
  border: 1px solid var(--ff-border);
  border-radius: 14px;
  background: var(--ff-surface);
}

.features span {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--ff-accent-soft);
  color: var(--ff-accent-text);
}

.features svg {
  display: block;
  width: 22px;
  height: 22px;
}

.features h2 {
  margin: 16px 0 6px;
  font-size: 18px;
  line-height: 1.35;
}

.features p {
  margin: 0;
  color: var(--ff-muted);
  font-size: 14.5px;
  text-wrap: pretty;
}

@media (max-width: 760px) {
  .features {
    grid-template-columns: 1fr;
    gap: 12px;
  }
}

/* Privacy */
.policy {
  max-width: 780px;
  margin-inline: auto;
  padding-block: 16px 24px;
}

.policy h1 {
  margin: 0 0 8px;
  font-size: clamp(26px, 4vw, 32px);
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.policy h2 {
  margin: 32px 0 10px;
  font-size: 19px;
  line-height: 1.5;
}

.policy p,
.policy li {
  font-size: 15.5px;
  line-height: 1.85;
}

.policy p {
  margin: 12px 0;
}

.policy ul {
  padding-left: 22px;
}

.policy li {
  margin: 8px 0;
}

.policy a {
  color: var(--ff-accent-text);
  overflow-wrap: anywhere;
}

.policy .meta {
  color: var(--ff-subtle);
  font-size: 14px;
}

.policy .intro {
  padding: 14px 18px;
  border-left: 4px solid var(--ff-accent);
  border-radius: 6px;
  background: var(--ff-accent-soft);
}

.policy article + article {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--ff-divider);
}

/* With JS only the chosen language shows; without it, both do. */
:root[data-lang="zh"] .policy [data-for="en"],
:root[data-lang="en"] .policy [data-for="zh"] {
  display: none;
}

:root[data-lang] .policy article + article {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

@media (max-width: 480px) {
  .top,
  .page,
  .foot {
    padding-inline: 16px;
  }

  .cta > * {
    flex: 1 1 40%;
    padding: 0 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .pill,
  .cta > * {
    transition: none;
  }
}