/* eebookk 官网
   视觉基线：纸张底色 + 品牌绿 + 墨色正文；与桌面端保持同一套主色与圆角语言。 */

:root {
  --paper: #f7f6f3;
  --paper-2: #f1eee7;
  --paper-3: #eae6dc;
  --white: #ffffff;
  --ink: #171613;
  --ink-2: #514e47;
  --ink-3: #6f6b63;
  --ink-4: #a5a097;
  --line: #e6e2d9;
  --line-2: #d8d3c7;
  --green: #07c160;
  --green-deep: #05964a;
  --green-ink: #067a41;
  --green-soft: #e7f8ee;
  --green-ink-on: #052715;
  --warn: #e8890c;
  --danger: #e34747;
  --dark: #14130f;
  --dark-2: #1c1b16;
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --shadow-window: 0 2px 4px rgba(23, 22, 19, 0.05), 0 18px 40px -18px rgba(23, 22, 19, 0.22), 0 60px 120px -50px rgba(23, 22, 19, 0.4);
  --shadow-card: 0 1px 1px rgba(23, 22, 19, 0.03), 0 18px 40px -30px rgba(23, 22, 19, 0.35);
  --font-sans: "Inter", "SF Pro Text", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  --font-mono: "SFMono-Regular", "Cascadia Code", "JetBrains Mono", "Consolas", monospace;
  --container: 1200px;
  --header-h: 72px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 24px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

::selection { background: rgba(7, 193, 96, 0.22); color: var(--ink); }

img { max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
h1, h2, h3, h4, p, dl, dd, figure { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: rgba(23, 22, 19, 0.055);
  border: 1px solid rgba(23, 22, 19, 0.06);
  border-radius: 5px;
  padding: 0.08em 0.36em;
  white-space: nowrap;
}

.icon { width: 20px; height: 20px; flex: none; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.icon--github { fill: currentColor; stroke: none; }
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

.container {
  width: min(var(--container), 100% - 2 * clamp(20px, 4.2vw, 48px));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: -80px;
  z-index: 200;
  padding: 12px 18px;
  border-radius: 10px;
  background: var(--ink);
  color: var(--paper);
  font-size: 14px;
  transition: top 0.2s var(--ease);
}
.skip-link:focus { top: 16px; }

:where(a, button, summary):focus-visible {
  outline: 2px solid var(--green-deep);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ============ 按钮 ============ */

.btn {
  --btn-h: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  height: var(--btn-h);
  padding: 0 22px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
  white-space: nowrap;
  transition: transform 0.25s var(--ease), background 0.25s var(--ease), border-color 0.25s var(--ease), box-shadow 0.25s var(--ease), color 0.2s;
}
.btn .icon { width: 18px; height: 18px; }
.btn-lg { --btn-h: 54px; padding: 0 27px; font-size: 15.5px; }
.btn-sm { --btn-h: 38px; padding: 0 17px; font-size: 14px; }

.btn-primary {
  color: var(--green-ink-on);
  background: linear-gradient(180deg, #0ad06a 0%, var(--green) 55%, #06b458 100%);
  border-color: rgba(4, 120, 58, 0.28);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.4) inset, 0 10px 26px -12px rgba(5, 150, 74, 0.75);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 1px 0 rgba(255, 255, 255, 0.45) inset, 0 16px 34px -14px rgba(5, 150, 74, 0.8); }
.btn-primary:active { transform: translateY(0); }

.btn-ghost {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.72);
  border-color: var(--line-2);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.7) inset;
  backdrop-filter: blur(6px);
}
.btn-ghost:hover { background: var(--white); border-color: #c3bdaf; transform: translateY(-1px); }

/* ============ 顶部导航 ============ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(247, 246, 243, 0.78);
  backdrop-filter: saturate(1.5) blur(16px);
  -webkit-backdrop-filter: saturate(1.5) blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s var(--ease), background 0.25s var(--ease);
}
.site-header.is-scrolled {
  border-bottom-color: var(--line);
  background: rgba(247, 246, 243, 0.92);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: none;
}
.brand-logo { width: 38px; height: 38px; display: block; }
.brand-name { font-size: 21px; font-weight: 650; letter-spacing: -0.035em; line-height: 1; }
.brand-sub {
  margin-left: 2px;
  padding: 3px 7px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.02em;
  color: var(--ink-3);
  line-height: 1.2;
  transform: translateY(1px);
}

.nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav a {
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 14.5px;
  color: var(--ink-2);
  transition: color 0.2s, background 0.2s;
}
.nav a:hover { color: var(--ink); background: rgba(23, 22, 19, 0.045); }
.nav-github {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.nav-github .icon { width: 16px; height: 16px; fill: currentColor; stroke: none; }
.header-cta { margin-left: 6px; }

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  margin-left: auto;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--white);
}
.nav-toggle .icon { width: 20px; height: 20px; }
.nav-toggle .icon-close { display: none; }
.nav-toggle[aria-expanded="true"] .icon-menu { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }

/* ============ Hero ============ */

.hero {
  position: relative;
  padding: clamp(56px, 7.5vw, 100px) 0 clamp(40px, 5vw, 64px);
  isolation: isolate;
  overflow-x: clip;
}
.hero-glow {
  position: absolute;
  inset: -20% -10% auto;
  height: 900px;
  z-index: -1;
  background:
    radial-gradient(58% 52% at 50% 18%, rgba(7, 193, 96, 0.16), transparent 72%),
    radial-gradient(40% 38% at 16% 6%, rgba(7, 193, 96, 0.07), transparent 70%),
    radial-gradient(36% 40% at 86% 2%, rgba(255, 255, 255, 0.9), transparent 70%);
  pointer-events: none;
}
.hero-copy {
  max-width: 920px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 14px 7px 11px;
  border-radius: 999px;
  border: 1px solid var(--line-2);
  background: rgba(255, 255, 255, 0.66);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.8) inset;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  color: var(--ink-3);
  backdrop-filter: blur(8px);
}
.pulse {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 0 rgba(7, 193, 96, 0.45);
  animation: pulse 2.6s infinite;
  flex: none;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(7, 193, 96, 0.4); }
  70% { box-shadow: 0 0 0 7px rgba(7, 193, 96, 0); }
  100% { box-shadow: 0 0 0 0 rgba(7, 193, 96, 0); }
}

.hero h1 {
  margin-top: 26px;
  font-size: clamp(42px, 7.4vw, 88px);
  line-height: 1.06;
  letter-spacing: -0.045em;
  font-weight: 700;
  color: var(--ink);
}
.mark {
  position: relative;
  display: inline;
  background-image: linear-gradient(180deg, transparent 60%, rgba(7, 193, 96, 0.24) 60%, rgba(7, 193, 96, 0.24) 94%, transparent 94%);
  background-repeat: no-repeat;
  padding: 0 0.02em;
}
.hero-lede {
  margin-top: 22px;
  max-width: 650px;
  font-size: clamp(15.5px, 1.35vw, 18px);
  line-height: 1.8;
  color: var(--ink-2);
  text-wrap: pretty;
}
.hero-actions {
  margin-top: 30px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}
.hero-meta {
  margin-top: 16px;
  font-size: 12.5px;
  letter-spacing: 0.01em;
  color: var(--ink-3);
}

.hero-visual {
  position: relative;
  margin-top: clamp(42px, 6vw, 72px);
  padding-inline: clamp(0px, 2vw, 20px);
}
.hero-window {
  position: relative;
  border-radius: 20px;
  overflow: hidden;
  border: 1px solid rgba(23, 22, 19, 0.13);
  background: var(--white);
  box-shadow: var(--shadow-window);
  line-height: 0;
}
.window-bar {
  height: 38px;
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 0 14px;
  background: linear-gradient(180deg, #fbfaf8, #f3f1ec);
  border-bottom: 1px solid var(--line);
  line-height: 1;
}
.wb-dot { width: 9px; height: 9px; border-radius: 50%; background: #d7d2c6; }
.wb-dot--g { background: var(--green); box-shadow: 0 0 0 3px rgba(7, 193, 96, 0.12); }
.wb-title {
  margin-left: 10px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.04em;
  color: var(--ink-4);
}
.hero-window img { display: block; width: 100%; height: auto; }

.float-card {
  position: absolute;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 13px 17px;
  border-radius: 14px;
  border: 1px solid rgba(23, 22, 19, 0.09);
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 18px 40px -22px rgba(23, 22, 19, 0.45);
  backdrop-filter: blur(12px);
  line-height: 1.25;
  z-index: 2;
  animation: float 7s ease-in-out infinite alternate;
}
.float-kicker { font-size: 11px; color: var(--ink-3); letter-spacing: 0.01em; }
.float-card strong { font-size: 25px; font-weight: 600; letter-spacing: -0.04em; color: var(--ink); font-variant-numeric: tabular-nums; }
.float-card strong span { font-size: 13px; color: var(--ink-3); margin-left: 1px; }
.float-strong-sm { font-size: 16px !important; letter-spacing: -0.02em !important; }
.float-card--a { left: -34px; top: 20%; }
.float-card--b { right: -30px; bottom: 17%; animation-delay: -3.4s; }
@keyframes float {
  from { transform: translateY(-5px); }
  to { transform: translateY(7px); }
}

/* ============ 数据条 ============ */

.trust {
  border-block: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.44);
}
.trust-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}
.trust-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 26px 30px;
  border-left: 1px solid var(--line);
}
.trust-item:first-child { border-left: 0; padding-left: 0; }
.trust-num {
  font-size: 29px;
  font-weight: 650;
  letter-spacing: -0.045em;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}
.trust-num span { font-size: 14px; font-weight: 500; color: var(--ink-3); margin-left: 2px; letter-spacing: 0; }
.trust-label { font-size: 12.5px; color: var(--ink-3); letter-spacing: 0.005em; }

/* ============ 通用 section ============ */

.section { padding-block: clamp(72px, 9vw, 124px); }
.section-head { max-width: 860px; margin-bottom: clamp(38px, 5vw, 62px); }
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--green-ink);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: currentColor;
  opacity: 0.55;
}
.section-head h2 {
  margin-top: 16px;
  font-size: clamp(31px, 3.55vw, 46px);
  line-height: 1.16;
  letter-spacing: -0.04em;
  font-weight: 700;
  text-wrap: balance;
}
.section-head > p:not(.eyebrow) {
  margin-top: 18px;
  max-width: 660px;
  font-size: 16.5px;
  line-height: 1.8;
  color: var(--ink-2);
  text-wrap: pretty;
}
.section-head a { color: var(--green-ink); border-bottom: 1px solid rgba(6, 122, 65, 0.3); }
.section-head a:hover { border-color: var(--green-ink); }

/* ============ 功能 bento ============ */

.bento {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 18px;
}
.bcard {
  grid-column: span 4;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--white);
  overflow: hidden;
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
}
.bcard:hover {
  transform: translateY(-3px);
  border-color: #d9d3c6;
  box-shadow: var(--shadow-card);
}
.bcard--wide { grid-column: span 6; flex-direction: row; align-items: stretch; gap: 24px; min-height: 306px; }
.bcard-body { display: flex; flex-direction: column; gap: 13px; flex: 1; min-width: 0; }
.bcard h3 { font-size: 21px; font-weight: 650; letter-spacing: -0.025em; line-height: 1.3; }
.bcard p { font-size: 14.5px; line-height: 1.75; color: var(--ink-2); }
.icon-tile {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--green-soft);
  border: 1px solid rgba(7, 193, 96, 0.16);
  color: var(--green-ink);
  margin-bottom: 2px;
}
.icon-tile .icon { width: 21px; height: 21px; }

.chips { display: flex; flex-wrap: wrap; gap: 6px; margin-top: auto; padding-top: 8px; }
.chip {
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--paper);
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--ink-3);
  white-space: nowrap;
}
.bcard code { background: rgba(23, 22, 19, 0.05); }

.bcard-shot {
  position: absolute;
  right: -6%;
  bottom: -16%;
  width: 54%;
  height: auto;
  border-radius: 12px;
  border: 1px solid rgba(23, 22, 19, 0.12);
  box-shadow: 0 20px 40px -20px rgba(23, 22, 19, 0.4);
  transform: rotate(-3.2deg);
  transition: transform 0.5s var(--ease);
  pointer-events: none;
}
.bcard:hover .bcard-shot { transform: rotate(-2deg) translateY(-4px); }
.bcard--wide:first-child .bcard-body { max-width: 58%; }

.gauge-wrap {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 16px;
  flex: none;
  width: 44%;
}
.gauge {
  width: 132px;
  height: 132px;
  margin-inline: auto;
  border-radius: 50%;
  background: conic-gradient(var(--warn) 0 60%, #ece8df 60% 100%);
  display: grid;
  place-items: center;
  position: relative;
}
.gauge::after {
  content: "";
  position: absolute;
  inset: 9px;
  border-radius: 50%;
  background: var(--white);
}
.gauge span {
  position: relative;
  z-index: 1;
  font-size: 31px;
  font-weight: 650;
  letter-spacing: -0.04em;
  line-height: 1;
}
.gauge small { font-size: 12px; font-weight: 500; color: var(--ink-3); margin-left: 2px; letter-spacing: 0; }
.issue-stack { display: flex; flex-direction: column; gap: 6px; }
.issue {
  display: flex;
  align-items: baseline;
  gap: 6px;
  font-size: 11.5px;
  color: var(--ink-3);
  padding: 5px 9px;
  border-radius: 7px;
  background: var(--paper);
  border: 1px solid var(--line);
  font-variant-numeric: tabular-nums;
}
.issue span { font-size: 10.5px; }
.issue--high { color: #a5462d; background: #fcf0ec; border-color: #f3d9d1; }
.issue--low { color: #7a6a3f; background: #f7f2e5; border-color: #eee3c9; }

/* ============ 产品导览 ============ */

.tour {
  background: var(--white);
  border-block: 1px solid var(--line);
}
.tour-layout {
  display: grid;
  grid-template-columns: 322px minmax(0, 1fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: start;
}
.tour-rail {
  position: sticky;
  top: calc(var(--header-h) + 28px);
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 6px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--paper);
}
.tour-tab {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  grid-template-rows: auto auto;
  column-gap: 6px;
  row-gap: 1px;
  align-items: center;
  padding: 10px 12px;
  border-radius: 11px;
  border: 1px solid transparent;
  text-align: left;
  color: var(--ink-2);
  transition: background 0.2s, color 0.2s, border-color 0.2s, box-shadow 0.2s;
}
.tour-idx {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 10.5px;
  color: var(--ink-3);
  letter-spacing: 0.02em;
}
.tour-label { font-size: 14.5px; font-weight: 550; letter-spacing: -0.01em; line-height: 1.4; }
.tour-sub { font-size: 11.5px; color: var(--ink-3); line-height: 1.4; }
.tour-tab:hover { background: rgba(255, 255, 255, 0.75); color: var(--ink); }
.tour-tab.is-active {
  background: var(--white);
  border-color: var(--line);
  color: var(--ink);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.8) inset, 0 8px 20px -16px rgba(23, 22, 19, 0.5);
}
.tour-tab.is-active .tour-idx { color: var(--green-ink); }
.tour-tab.is-active .tour-label { font-weight: 650; }

.tour-panel { animation: panel-in 0.4s var(--ease); }
.tour-panel[hidden] { display: none; }
@keyframes panel-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
.shot-frame {
  position: relative;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--line-2);
  background: var(--paper-2);
  box-shadow: 0 2px 4px rgba(23, 22, 19, 0.04), 0 30px 70px -40px rgba(23, 22, 19, 0.55);
  line-height: 0;
}
.shot-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.25);
  pointer-events: none;
}
.shot-frame img { display: block; width: 100%; height: auto; aspect-ratio: 16 / 9; object-fit: cover; object-position: top center; }
.tour-copy { margin-top: 26px; max-width: 760px; }
.tour-copy h3 { font-size: 23px; font-weight: 650; letter-spacing: -0.03em; line-height: 1.35; }
.tour-copy > p { margin-top: 10px; font-size: 15px; line-height: 1.8; color: var(--ink-2); }
.ticks {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px 22px;
}
.ticks li {
  position: relative;
  padding-left: 24px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--ink-2);
}
.ticks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.42em;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--green-soft);
  border: 1px solid rgba(7, 193, 96, 0.28);
}
.ticks li::after {
  content: "";
  position: absolute;
  left: 4px;
  top: 0.72em;
  width: 5px;
  height: 3px;
  border-left: 1.5px solid var(--green-ink);
  border-bottom: 1.5px solid var(--green-ink);
  transform: rotate(-45deg);
}

/* ============ 更多功能 ============ */

.more-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.more-item {
  padding: 27px 26px 30px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 9px;
  background: transparent;
  transition: background 0.25s var(--ease);
}
.more-item:hover { background: rgba(255, 255, 255, 0.72); }
.more-item .icon { width: 21px; height: 21px; color: var(--green-ink); margin-bottom: 6px; }
.more-item h3 { font-size: 16px; font-weight: 650; letter-spacing: -0.015em; }
.more-item p { font-size: 13.5px; line-height: 1.7; color: var(--ink-3); }

/* ============ 与 calibre 的关系（深色） ============ */

.philosophy {
  position: relative;
  background: var(--dark);
  color: #f2efe7;
  overflow: hidden;
  isolation: isolate;
}
.philosophy::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(52% 60% at 82% 4%, rgba(7, 193, 96, 0.16), transparent 70%),
    radial-gradient(36% 46% at 8% 100%, rgba(255, 255, 255, 0.05), transparent 70%);
}
.section-head--dark .eyebrow { color: #4ddc8d; }
.section-head--dark h2 { color: #f5f2ea; }
.section-head--dark > p:not(.eyebrow) { color: rgba(242, 239, 231, 0.62); }
.principles {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}
.principle {
  padding: 26px 26px 6px 0;
  border-right: 1px solid rgba(255, 255, 255, 0.12);
}
.principle:last-child { border-right: 0; }
.principle:nth-child(n + 2) { padding-left: 26px; }
.principle-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: #4ddc8d;
}
.principle h3 { margin-top: 14px; font-size: 17px; font-weight: 600; letter-spacing: -0.02em; color: #f5f2ea; }
.principle p { margin-top: 8px; font-size: 13.5px; line-height: 1.75; color: rgba(242, 239, 231, 0.6); }
.philosophy-note {
  margin-top: 46px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 12px;
  letter-spacing: 0.01em;
  color: rgba(242, 239, 231, 0.5);
}

/* ============ 下载 ============ */

.download { background: var(--paper); }
.download-card {
  display: grid;
  grid-template-columns: minmax(0, 1.32fr) minmax(300px, 0.68fr);
  border: 1px solid var(--line-2);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--white);
  box-shadow: 0 1px 2px rgba(23, 22, 19, 0.04), 0 40px 80px -60px rgba(23, 22, 19, 0.55);
}
.download-main {
  padding: clamp(28px, 3.6vw, 46px);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(7, 193, 96, 0.09), transparent 55%),
    linear-gradient(180deg, #fff, #fbfaf7);
}
.dl-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--ink-3);
}
.dl-version {
  margin-top: 14px;
  font-size: clamp(32px, 3.6vw, 42px);
  font-weight: 700;
  letter-spacing: -0.045em;
  line-height: 1.1;
}
.dl-version span { color: var(--ink-3); font-weight: 500; }
.dl-sub { margin-top: 6px; font-size: 14px; color: var(--ink-3); }

.dl-meta {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
}
.dl-meta > div { background: var(--white); padding: 11px 15px; }
.dl-meta dt { font-size: 10.5px; letter-spacing: 0.05em; color: var(--ink-3); text-transform: uppercase; }
.dl-meta dd { margin-top: 2px; font-size: 13px; font-weight: 550; color: var(--ink); font-variant-numeric: tabular-nums; }

.download-actions { margin-top: 26px; display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.dl-note { margin-top: 16px; max-width: 540px; font-size: 12px; line-height: 1.7; color: var(--ink-3); }
.dl-note a { color: var(--green-ink); border-bottom: 1px solid rgba(6, 122, 65, 0.3); }
.dl-note a:hover { border-color: var(--green-ink); }

.steps {
  padding: clamp(26px, 3.2vw, 40px);
  background: var(--paper-2);
  border-left: 1px solid var(--line-2);
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
}
.steps li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 14px;
  padding: 17px 0;
  border-top: 1px solid rgba(23, 22, 19, 0.09);
}
.steps li:first-child { border-top: 0; }
.step-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--green-ink);
  padding-top: 3px;
}
.steps h4 { font-size: 15px; font-weight: 650; letter-spacing: -0.015em; }
.steps p { margin-top: 4px; font-size: 12.8px; line-height: 1.65; color: var(--ink-3); }

.requirements {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  background: var(--line);
}
.requirements > div { padding: 22px 24px; background: var(--paper); }
.requirements h3 { font-size: 13px; font-weight: 650; letter-spacing: 0.02em; color: var(--ink); }
.requirements p { margin-top: 6px; font-size: 12.5px; line-height: 1.7; color: var(--ink-3); }

/* ============ FAQ ============ */

.faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
  gap: clamp(34px, 6vw, 90px);
  align-items: start;
}
.section-head--sticky { position: sticky; top: calc(var(--header-h) + 30px); margin-bottom: 0; }
.faq .section-head h2 { font-size: clamp(29px, 3.2vw, 41px); }
.faq-list { border-top: 1px solid var(--line-2); }
.faq-list details { border-bottom: 1px solid var(--line-2); }
.faq-list summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 21px 2px;
  font-size: 16px;
  font-weight: 550;
  letter-spacing: -0.01em;
  cursor: pointer;
  list-style: none;
  transition: color 0.2s;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary:hover { color: var(--green-ink); }
.faq-list summary .icon { width: 18px; height: 18px; color: var(--ink-4); transition: transform 0.3s var(--ease), color 0.2s; }
.faq-list details[open] summary .icon { transform: rotate(180deg); color: var(--green-ink); }
.faq-body { padding: 0 36px 22px 2px; }
.faq-body p { font-size: 14px; line-height: 1.8; color: var(--ink-2); }

/* ============ 页脚 ============ */

.site-footer {
  background: var(--dark);
  color: rgba(242, 239, 231, 0.66);
  padding-top: clamp(52px, 6vw, 76px);
}
.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) repeat(3, minmax(0, 0.7fr));
  gap: clamp(30px, 4vw, 60px);
  padding-bottom: clamp(42px, 5vw, 64px);
}
.footer-brand { display: flex; flex-direction: column; align-items: flex-start; }
.brand--footer { gap: 12px; }
.brand--footer .brand-logo { width: 46px; height: 46px; }
.brand--footer .brand-name { color: #f5f2ea; font-size: 26px; }
.footer-brand p { margin-top: 18px; font-size: 13.5px; line-height: 1.8; color: rgba(242, 239, 231, 0.5); }
.footer-social { margin-top: 22px; display: flex; gap: 8px; }
.footer-social a {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  color: rgba(242, 239, 231, 0.72);
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}
.footer-social a:hover { background: rgba(255, 255, 255, 0.08); color: #fff; border-color: rgba(255, 255, 255, 0.26); }
.footer-social .icon { width: 18px; height: 18px; fill: currentColor; stroke: none; }

.footer-col { display: flex; flex-direction: column; gap: 9px; padding-top: 4px; }
.footer-col h3 {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(242, 239, 231, 0.5);
  margin-bottom: 7px;
}
.footer-col a, .footer-col span { font-size: 13.5px; line-height: 1.5; color: rgba(242, 239, 231, 0.65); transition: color 0.2s; }
.footer-col a:hover { color: #4ddc8d; }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 22px 26px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.footer-bottom p { font-size: 11.5px; color: rgba(242, 239, 231, 0.46); }

/* ============ 入场动画 ============ */

.reveal { opacity: 1; transform: none; }
.js .reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.js .reveal.is-in { opacity: 1; transform: none; }
.js .bcard.reveal:nth-child(2) { transition-delay: 0.05s; }
.js .bcard.reveal:nth-child(3) { transition-delay: 0.1s; }
.js .bcard.reveal:nth-child(4) { transition-delay: 0.05s; }
.js .bcard.reveal:nth-child(5) { transition-delay: 0.1s; }
.js .principle.reveal:nth-child(2) { transition-delay: 0.06s; }
.js .principle.reveal:nth-child(3) { transition-delay: 0.12s; }
.js .principle.reveal:nth-child(4) { transition-delay: 0.18s; }

/* 截图模式：?static=1 时全部展开，方便整页截图与存档 */
.static .reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
.static .float-card { animation: none; }
.static .tour-panel { animation: none; }

/* ============ 响应式 ============ */

@media (max-width: 1080px) {
  .float-card { display: none; }
  .bcard--wide { min-height: 290px; }
  .bcard-shot { width: 56%; }
  .principles { grid-template-columns: repeat(2, 1fr); }
  .principle:nth-child(2) { border-right: 0; padding-left: 26px; }
  .principle:nth-child(3), .principle:nth-child(4) { border-top: 1px solid rgba(255, 255, 255, 0.12); }
  .principle:nth-child(3) { padding-left: 0; }
}

@media (max-width: 960px) {
  .brand-sub { display: none; }
  .tour-layout { grid-template-columns: 1fr; }
  .tour-rail {
    position: static;
    flex-direction: row;
    overflow-x: auto;
    gap: 6px;
    padding: 6px;
    scrollbar-width: none;
  }
  .tour-rail::-webkit-scrollbar { display: none; }
  .tour-tab {
    flex: none;
    grid-template-columns: auto;
    grid-template-rows: auto;
    padding: 9px 14px;
    border-radius: 999px;
    white-space: nowrap;
  }
  .tour-idx, .tour-sub { display: none; }
  .tour-label { font-size: 13.5px; }
  .tour-copy h3 { font-size: 21px; }
  .download-card { grid-template-columns: 1fr; }
  .steps { border-left: 0; border-top: 1px solid var(--line-2); }
  .requirements { grid-template-columns: 1fr; }
  .faq-layout { grid-template-columns: 1fr; }
  .section-head--sticky { position: static; margin-bottom: 30px; }
  .more-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 820px) {
  .nav {
    position: absolute;
    top: calc(var(--header-h) + 8px);
    left: clamp(16px, 4vw, 28px);
    right: clamp(16px, 4vw, 28px);
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 10px;
    border: 1px solid var(--line-2);
    border-radius: 16px;
    background: #ffffff;
    box-shadow: 0 24px 60px -30px rgba(23, 22, 19, 0.5);
    backdrop-filter: blur(20px);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 0.25s var(--ease), transform 0.25s var(--ease), visibility 0.25s;
  }
  .nav a { padding: 12px 14px; border-radius: 9px; font-size: 15px; }
  .nav-github { justify-content: flex-start; }
  .nav-toggle { display: flex; }
  .header-cta { display: none; }
  .site-header.nav-open .nav { opacity: 1; visibility: visible; transform: none; }
  .site-header.nav-open { border-bottom-color: var(--line); }

  .bcard, .bcard--wide { grid-column: span 12; }
  .bcard--wide { min-height: 0; }
  .bcard--wide:first-child .bcard-body { max-width: 62%; }
  .bcard-shot { width: 44%; right: -4%; bottom: -10%; }
  .gauge-wrap { width: 40%; }
  .gauge { width: 108px; height: 108px; }
  .trust-inner { grid-template-columns: repeat(2, 1fr); }
  .trust-item { padding: 20px 24px; }
  .trust-item:nth-child(odd) { border-left: 0; padding-left: 0; }
  .trust-item:nth-child(-n + 2) { border-bottom: 1px solid var(--line); }
}

@media (max-width: 640px) {
  .principles { grid-template-columns: 1fr; }
  .principle,
  .principle:nth-child(n + 2) {
    padding: 21px 0 18px;
    border-right: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
  }
  .principle:first-child { border-top: 0; padding-top: 6px; }
  .principle h3 { margin-top: 10px; }
}

@media (max-width: 620px) {
  :root { --radius-lg: 20px; --radius-md: 16px; }
  .hero { padding-top: 44px; }
  .hero h1 { font-size: clamp(36px, 10.6vw, 52px); letter-spacing: -0.04em; }
  .hero-lede { font-size: 15px; line-height: 1.75; }
  .hero-actions { width: 100%; flex-direction: column; align-items: stretch; }
  .hero-actions .btn { width: 100%; }
  .hero-meta { line-height: 1.6; }
  .window-bar { height: 34px; }
  .wb-title { display: none; }
  .section-head h2 { font-size: clamp(28px, 8vw, 38px); }
  .section-head > p:not(.eyebrow) { font-size: 15px; }
  .bcard { padding: 22px; }
  .bcard--wide { flex-direction: column; }
  .bcard--wide:first-child .bcard-body { max-width: 100%; }
  .bcard-shot { position: static; width: 100%; margin-top: 4px; transform: none; border-radius: 10px; }
  .bcard:hover .bcard-shot { transform: none; }
  .gauge-wrap { width: 100%; flex-direction: row; align-items: center; gap: 20px; }
  .gauge { flex: none; margin-inline: 0; }
  .issue-stack { flex: 1; }
  .ticks { grid-template-columns: 1fr; }
  .more-grid { grid-template-columns: 1fr; }
  .more-item { padding: 22px; }
  .principle { padding-right: 16px !important; }
  .philosophy-note { margin-top: 30px; }
  .dl-meta { grid-template-columns: 1fr; }
  .download-actions { flex-direction: column; align-items: stretch; }
  .download-actions .btn { width: 100%; }
  .steps { padding: 22px; }
  .requirements > div { padding: 18px 20px; }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 28px 20px; }
  .brand--footer .brand-name { font-size: 23px; }
  .float-card { display: none; }
}

@media (max-width: 420px) {
  .footer-top { grid-template-columns: 1fr; }
  .footer-brand { grid-column: auto; }
  .trust-item { padding: 16px 16px; }
  .trust-num { font-size: 25px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .js .reveal { opacity: 1; transform: none; }
}