/* =========================================================
   Qivomo 官网样式
   设计基调：莫兰迪蓝灰（应用主色 #17202A / 辅色 #A6B8C9）
   ========================================================= */

/* ---------- 主题变量 ---------- */
html[data-theme="light"] {
  color-scheme: light;

  --bg: #f5f7f9;
  --bg-soft: #edf1f5;
  --surface: #ffffff;
  --surface-2: #f7f9fb;
  --surface-3: #eef2f6;

  --text: #17202a;
  --text-2: #52606d;
  --text-3: #63737f;

  --line: rgba(23, 32, 42, 0.1);
  --line-strong: rgba(23, 32, 42, 0.18);

  --accent: #4c6e8b;
  --accent-hover: #3d5c77;
  --accent-soft: rgba(76, 110, 139, 0.1);
  --accent-line: rgba(76, 110, 139, 0.28);
  --on-accent: #ffffff;

  --ok: #3d7a5d;
  --no: #a9574f;

  --nav-bg: rgba(245, 247, 249, 0.78);
  --shadow-sm: 0 1px 2px rgba(16, 24, 32, 0.04), 0 6px 18px rgba(16, 24, 32, 0.04);
  --shadow-md: 0 2px 4px rgba(16, 24, 32, 0.04), 0 16px 36px rgba(16, 24, 32, 0.07);
  --shadow-lg: 0 30px 70px rgba(16, 24, 32, 0.16);

  --glow-1: rgba(166, 184, 201, 0.34);
  --glow-2: rgba(196, 182, 205, 0.22);
}

html[data-theme="dark"] {
  color-scheme: dark;

  --bg: #0d1217;
  --bg-soft: #11171d;
  --surface: #161d25;
  --surface-2: #1b242d;
  --surface-3: #202b35;

  --text: #e9eef4;
  --text-2: #a7b4c0;
  --text-3: #77879a;

  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.18);

  --accent: #a6b8c9;
  --accent-hover: #bccbd9;
  --accent-soft: rgba(166, 184, 201, 0.12);
  --accent-line: rgba(166, 184, 201, 0.3);
  --on-accent: #101820;

  --ok: #7cc0a0;
  --no: #e0958c;

  --nav-bg: rgba(13, 18, 23, 0.72);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 20px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 2px 6px rgba(0, 0, 0, 0.45), 0 20px 44px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 40px 90px rgba(0, 0, 0, 0.6);

  --glow-1: rgba(94, 122, 148, 0.28);
  --glow-2: rgba(120, 100, 140, 0.18);
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei",
    "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  transition: background-color 0.25s ease, color 0.25s ease;
}

/* 页面底部的柔光 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(720px 420px at 78% -8%, var(--glow-1), transparent 70%),
    radial-gradient(640px 400px at 6% 14%, var(--glow-2), transparent 72%);
  opacity: 0.9;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.18s ease;
}
a:hover { color: var(--accent-hover); }

h1, h2, h3, h4 {
  margin: 0;
  color: var(--text);
  line-height: 1.28;
  letter-spacing: -0.012em;
  font-weight: 650;
  text-wrap: balance;
}
p { margin: 0; }
.hero__lead,
.section__head .lead,
.download__sub,
.faq__body,
.notice__body p { text-wrap: pretty; }
ul, ol, dl, dd { margin: 0; padding: 0; }
li { list-style: none; }

code, kbd {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.88em;
  background: var(--surface-3);
  color: var(--text);
  border-radius: 6px;
  padding: 0.12em 0.42em;
  border: 1px solid var(--line);
  white-space: nowrap;
}

kbd { font-size: 0.8em; padding: 0.1em 0.38em; }

::selection { background: var(--accent); color: var(--on-accent); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.skip-link {
  position: absolute;
  top: -60px;
  left: 16px;
  z-index: 200;
  padding: 10px 16px;
  border-radius: 10px;
  background: var(--accent);
  color: var(--on-accent);
  font-size: 14px;
}
.skip-link:focus { top: 12px; color: var(--on-accent); }

.container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 28px;
  position: relative;
  z-index: 1;
}
.container--narrow { max-width: 860px; }

/* ---------- 顶部导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 60;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}
.nav.is-scrolled {
  background: var(--nav-bg);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  backdrop-filter: saturate(160%) blur(16px);
  border-bottom-color: var(--line);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.02);
}

.nav__inner {
  max-width: 1160px;
  margin: 0 auto;
  padding: 12px 28px;
  display: flex;
  align-items: center;
  gap: 22px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  flex-shrink: 0;
}
.brand:hover { color: var(--text); }
.brand img {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.14);
}
.brand__name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.brand__ver {
  font-size: 11.5px;
  color: var(--text-3);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 1px 8px;
  font-variant-numeric: tabular-nums;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: 8px;
  flex: 1;
}
.nav__links a {
  color: var(--text-2);
  font-size: 14.5px;
  padding: 7px 12px;
  border-radius: 9px;
  transition: color 0.16s ease, background-color 0.16s ease;
}
.nav__links a:hover { color: var(--text); background: var(--accent-soft); }

.nav__actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

/* 主题三段开关 */
.theme-switch {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--surface);
}
.theme-switch button {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  border: 0;
  background: transparent;
  color: var(--text-3);
  font: inherit;
  font-size: 12.5px;
  line-height: 1;
  padding: 7px 9px;
  border-radius: 8px;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease;
}
.theme-switch svg { width: 15px; height: 15px; flex: none; }
.theme-switch button:hover { color: var(--text); background: var(--accent-soft); }
.theme-switch button[aria-pressed="true"] {
  color: var(--text);
  background: var(--surface-3);
  box-shadow: inset 0 0 0 1px var(--line);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border: 1px solid transparent;
  border-radius: 12px;
  padding: 12px 20px;
  font-size: 14.5px;
  font-weight: 600;
  line-height: 1.2;
  cursor: pointer;
  white-space: nowrap;
  transition: transform 0.18s ease, box-shadow 0.18s ease,
    background-color 0.18s ease, border-color 0.18s ease, color 0.18s ease;
}
.btn svg { width: 18px; height: 18px; flex: none; }
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--accent);
  color: var(--on-accent);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.08), 0 8px 20px var(--accent-soft);
}
.btn--primary:hover {
  background: var(--accent-hover);
  color: var(--on-accent);
  box-shadow: 0 10px 26px var(--accent-soft);
}

.btn--ghost {
  background: var(--surface);
  color: var(--text);
  border-color: var(--line-strong);
}
.btn--ghost:hover {
  color: var(--text);
  border-color: var(--accent-line);
  box-shadow: var(--shadow-sm);
}

.btn--sm { padding: 9px 16px; font-size: 13.5px; border-radius: 10px; }
.btn--lg { padding: 15px 26px; font-size: 15.5px; border-radius: 14px; }

/* ---------- 首屏 ---------- */
.hero {
  position: relative;
  padding: 78px 0 84px;
  overflow: hidden;
}
.hero__glow {
  position: absolute;
  top: -160px;
  right: -120px;
  width: 720px;
  height: 620px;
  background: radial-gradient(circle at 50% 50%, var(--glow-1), transparent 66%);
  filter: blur(10px);
  pointer-events: none;
  z-index: 0;
}

.hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
  align-items: center;
  gap: 56px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px 6px 11px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text-2);
  font-size: 12.5px;
  letter-spacing: 0.01em;
  box-shadow: var(--shadow-sm);
}
.badge__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.hero h1 {
  margin: 22px 0 0;
  font-size: clamp(38px, 5vw, 58px);
  line-height: 1.14;
  letter-spacing: -0.028em;
  font-weight: 700;
}
.accent-text { color: var(--accent); }

.hero__lead {
  margin-top: 22px;
  max-width: 54ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--text-2);
}
.hero__lead strong { color: var(--text); font-weight: 600; }

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.hero__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 22px;
  font-size: 13px;
  color: var(--text-3);
}
.hero__meta i {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--text-3);
  opacity: 0.55;
}

/* 手机示意图 */
.hero__visual {
  position: relative;
  display: flex;
  justify-content: center;
  padding: 10px 0;
}

.device {
  position: relative;
  width: min(272px, 74vw);
  aspect-ratio: 9 / 19;
  padding: 8px;
  border-radius: 42px;
  background: linear-gradient(160deg, #39485a 0%, #1d2733 42%, #10161d 100%);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: var(--shadow-lg), inset 0 1px 0 rgba(255, 255, 255, 0.16);
  transform: rotate(-2.4deg);
  transition: transform 0.6s cubic-bezier(0.2, 0.7, 0.2, 1);
}
.device:hover { transform: rotate(0deg) translateY(-4px); }

.device__screen {
  position: relative;
  height: 100%;
  border-radius: 35px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(120% 70% at 82% 6%, rgba(166, 184, 201, 0.24), transparent 60%),
    linear-gradient(168deg, #2b3c4d 0%, #22303d 46%, #18222c 100%);
  color: #dbe5ee;
}

.device__topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 14px 14px 10px;
  font-size: 10.5px;
}
.device__app {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 999px;
  padding: 3px 9px 3px 4px;
  letter-spacing: 0.02em;
}
.device__app img { width: 16px; height: 16px; border-radius: 5px; }
.device__status {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  color: rgba(219, 229, 238, 0.72);
}
.device__live {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #8fd0b0;
  box-shadow: 0 0 0 3px rgba(143, 208, 176, 0.18);
}

.device__field {
  position: relative;
  flex: 1;
  margin: 4px 12px 0;
  border-radius: 18px;
  border: 1px solid rgba(255, 255, 255, 0.07);
  background:
    linear-gradient(transparent 0 0) ,
    repeating-linear-gradient(0deg, rgba(255, 255, 255, 0.045) 0 1px, transparent 1px 34px),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.045) 0 1px, transparent 1px 34px);
  overflow: hidden;
}

.key {
  position: absolute;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 15px;
  font-weight: 600;
  color: #e6eef6;
  background: rgba(166, 184, 201, 0.16);
  border: 1.5px solid rgba(166, 184, 201, 0.72);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.24), inset 0 0 18px rgba(166, 184, 201, 0.14);
  -webkit-backdrop-filter: blur(3px);
  backdrop-filter: blur(3px);
}
.key--w { left: 13%; top: 20%; }
.key--a { left: 6%; top: 38%; }
.key--s { left: 18%; top: 52%; }
.key--d { left: 30%; top: 38%; }

.look-ring {
  position: absolute;
  right: 9%;
  top: 30%;
  width: 92px;
  height: 92px;
  border-radius: 50%;
  border: 1.5px dashed rgba(219, 229, 238, 0.5);
  box-shadow: inset 0 0 26px rgba(166, 184, 201, 0.12);
}
.look-ring::after {
  content: "";
  position: absolute;
  inset: 38%;
  border-radius: 50%;
  border: 1px solid rgba(219, 229, 238, 0.55);
}
.look-label {
  position: absolute;
  right: 9%;
  top: calc(30% + 100px);
  width: 92px;
  text-align: center;
  font-size: 10px;
  color: rgba(219, 229, 238, 0.6);
  letter-spacing: 0.08em;
}

.device__ball {
  position: absolute;
  right: 18px;
  bottom: 58px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: radial-gradient(circle at 32% 28%, #c8d5e1, #90a6ba 68%, #7b90a4);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.6);
}
.device__ball span {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid rgba(23, 32, 42, 0.5);
}
.device__ball::after {
  content: "";
  position: absolute;
  inset: -5px;
  border-radius: 50%;
  border: 1px solid rgba(166, 184, 201, 0.3);
}

.device__hint {
  padding: 14px 16px 20px;
  text-align: center;
  font-size: 10px;
  letter-spacing: 0.04em;
  color: rgba(219, 229, 238, 0.5);
}

/* 浮在手机外的说明卡 */
.float-card {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 13px;
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  font-size: 12.5px;
  color: var(--text-2);
  white-space: nowrap;
}
.float-card__k {
  font-weight: 700;
  font-size: 15px;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}
.float-card__v { font-size: 12px; }
.float-card__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 3px rgba(61, 122, 93, 0.14);
}
.float-card--1 { top: 5%; left: -3%; }
.float-card--2 { bottom: 10%; right: -4%; }

/* ---------- 数据条 ---------- */
.strip {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--bg-soft);
}
.strip__inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  padding: 22px 28px;
}
.strip__item {
  display: flex;
  flex-direction: column;
  gap: 2px;
  text-align: center;
  position: relative;
}
.strip__item + .strip__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  height: 26px;
  width: 1px;
  background: var(--line);
}
.strip__item strong {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}
.strip__item span { font-size: 12px; color: var(--text-3); }

/* ---------- 通用区块 ---------- */
.section {
  position: relative;
  padding: 96px 0;
  scroll-margin-top: 84px;
}
.section--tight { padding: 10px 0 84px; }
.section--soft {
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section__head {
  max-width: 720px;
  margin-bottom: 44px;
}
.section__head--center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--accent);
  margin-bottom: 14px;
  text-transform: uppercase;
}

.section__head h2 {
  font-size: clamp(26px, 3.4vw, 38px);
  letter-spacing: -0.022em;
  line-height: 1.25;
}
.section__head .lead {
  margin-top: 14px;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-2);
  max-width: 62ch;
}
.section__head--center .lead { margin-left: auto; margin-right: auto; }

/* ---------- 网格与卡片 ---------- */
.grid { display: grid; gap: 18px; }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.card {
  padding: 28px;
  border-radius: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--accent-line);
  box-shadow: var(--shadow-md);
}
.card__icon {
  width: 42px;
  height: 42px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  background: var(--accent-soft);
  color: var(--accent);
  border: 1px solid var(--accent-line);
  margin-bottom: 18px;
}
.card__icon svg { width: 21px; height: 21px; }
.card h3 { font-size: 17.5px; margin-bottom: 8px; }
.card p { font-size: 14.5px; line-height: 1.8; color: var(--text-2); }

/* 边界清单 */
.boundary {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin-top: 22px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  overflow: hidden;
}
.boundary__col { padding: 30px 32px; }
.boundary__col + .boundary__col { border-left: 1px solid var(--line); }
.boundary__title {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--text-3);
  margin-bottom: 16px;
  font-weight: 600;
}
.check-list li,
.cross-list li {
  position: relative;
  padding-left: 26px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--text-2);
}
.check-list li + li,
.cross-list li + li { margin-top: 10px; }
.check-list li::before,
.cross-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.52em;
  width: 13px;
  height: 13px;
  border-radius: 50%;
}
.check-list li::before {
  background: var(--ok);
  box-shadow: 0 0 0 3px rgba(61, 122, 93, 0.12);
}
.cross-list li::before {
  background: var(--no);
  box-shadow: 0 0 0 3px rgba(169, 87, 79, 0.12);
}

/* 功能卡 */
.feature {
  padding: 24px 22px;
  border-radius: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}
.feature:hover {
  transform: translateY(-3px);
  border-color: var(--accent-line);
  box-shadow: var(--shadow-md);
}
.feature__icon {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  display: grid;
  place-items: center;
  background: var(--accent-soft);
  color: var(--accent);
  margin-bottom: 14px;
}
.feature__icon svg { width: 18px; height: 18px; }
.feature h3 { font-size: 15.5px; margin-bottom: 6px; }
.feature p { font-size: 13.5px; line-height: 1.78; color: var(--text-2); }

/* 优势 */
.reasons {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}
.reason {
  position: relative;
  padding: 30px 32px;
  border-radius: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  overflow: hidden;
}
.reason__num {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.reason h3 { font-size: 19px; margin: 8px 0 8px; }
.reason p { font-size: 14.5px; line-height: 1.8; color: var(--text-2); max-width: 46ch; }

.limits {
  margin-top: 18px;
  padding: 26px 30px 26px 28px;
  border-radius: 16px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
}
.limits__head {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 10px;
}
.limits__head svg { width: 18px; height: 18px; color: var(--accent); flex: none; }
.limits__head h3 { font-size: 15px; letter-spacing: 0; }
.limits ul li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--text-2);
}
.limits ul li + li { margin-top: 4px; }
.limits ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--text-3);
}

/* 步骤 */
.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  counter-reset: step;
}
.step {
  position: relative;
  padding: 28px;
  border-radius: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
}
.step__index {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--on-accent);
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 16px;
  box-shadow: 0 0 0 5px var(--accent-soft);
}
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14px; line-height: 1.8; color: var(--text-2); }

/* 系统要求 */
.specs {
  margin-top: 22px;
  padding: 28px 32px;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: var(--surface);
}
.specs h3 {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--text-3);
  font-weight: 600;
  margin-bottom: 6px;
}
.specs__list > div {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 20px;
  padding: 13px 0;
  border-bottom: 1px solid var(--line);
}
.specs__list > div:last-child { border-bottom: 0; padding-bottom: 2px; }
.specs dt { font-size: 14px; color: var(--text-2); }
.specs dd { font-size: 14px; color: var(--text); }

/* ---------- 下载 ---------- */
.download { padding-top: 20px; }
.download__panel {
  position: relative;
  padding: 56px 40px 40px;
  border-radius: 28px;
  border: 1px solid var(--line);
  background:
    radial-gradient(110% 80% at 50% -18%, var(--accent-soft), transparent 62%),
    linear-gradient(180deg, var(--surface), var(--surface-2));
  box-shadow: var(--shadow-md);
  text-align: center;
  overflow: hidden;
}
.download__panel::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
}

.download__head { position: relative; }
.download__logo {
  width: 72px;
  height: 72px;
  border-radius: 20px;
  margin: 0 auto 18px;
  box-shadow: 0 10px 26px rgba(23, 32, 42, 0.18);
}
.download .eyebrow { margin-bottom: 6px; }
.download h2 {
  font-size: clamp(26px, 3.6vw, 36px);
  letter-spacing: -0.022em;
}
.download__ver {
  font-variant-numeric: tabular-nums;
  color: var(--accent);
}
.download__sub {
  margin-top: 10px;
  font-size: 13.5px;
  color: var(--text-2);
}

.download__actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  max-width: 700px;
  margin: 32px auto 0;
  text-align: left;
}

.dl-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 20px;
  border-radius: 16px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  color: var(--text);
  transition: transform 0.2s ease, box-shadow 0.2s ease,
    border-color 0.2s ease, background-color 0.2s ease;
}
.dl-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-line);
  box-shadow: var(--shadow-md);
  color: var(--text);
}
.dl-card--primary {
  background: var(--accent);
  border-color: transparent;
  color: var(--on-accent);
  box-shadow: 0 12px 30px var(--accent-soft);
}
.dl-card--primary:hover {
  background: var(--accent-hover);
  color: var(--on-accent);
}
.dl-card__icon {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--accent);
  flex: none;
}
.dl-card--primary .dl-card__icon {
  background: rgba(255, 255, 255, 0.16);
  color: inherit;
}
.dl-card__icon svg { width: 20px; height: 20px; }
.dl-card__body {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 1;
  min-width: 0;
}
.dl-card__title { font-size: 15px; font-weight: 600; }
.dl-card__desc { font-size: 12px; opacity: 0.72; }
.dl-card__tag {
  font-size: 10.5px;
  letter-spacing: 0.08em;
  padding: 3px 7px;
  border-radius: 6px;
  border: 1px solid currentColor;
  opacity: 0.5;
  flex: none;
}

.download__links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-top: 22px;
  font-size: 13.5px;
  color: var(--text-3);
}
.download__links a { color: var(--text-2); }
.download__links a:hover { color: var(--accent); }

.download__note {
  max-width: 660px;
  margin: 24px auto 0;
  padding: 13px 18px;
  border-radius: 12px;
  border: 1px dashed var(--line-strong);
  background: var(--surface-2);
  font-size: 13px;
  line-height: 1.75;
  color: var(--text-2);
  text-align: left;
}
.download__note strong { color: var(--text); }
.download__note--muted {
  margin-top: 10px;
  border-style: solid;
  background: transparent;
  color: var(--text-3);
}

/* ---------- FAQ ---------- */
.faq {
  border-top: 1px solid var(--line);
}
.faq details {
  border-bottom: 1px solid var(--line);
}
.faq summary {
  position: relative;
  padding: 20px 44px 20px 0;
  font-size: 15.5px;
  font-weight: 550;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  transition: color 0.18s ease;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  position: absolute;
  right: 6px;
  top: 50%;
  width: 11px;
  height: 11px;
  margin-top: -6px;
  border-right: 1.6px solid var(--text-3);
  border-bottom: 1.6px solid var(--text-3);
  transform: rotate(45deg);
  transition: transform 0.22s ease, border-color 0.22s ease;
}
.faq summary:hover { color: var(--accent); }
.faq summary:hover::after { border-color: var(--accent); }
.faq details[open] summary::after {
  transform: rotate(-135deg);
  margin-top: -2px;
}
.faq__body {
  padding: 0 44px 22px 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-2);
}
.faq__body strong { color: var(--text); }

/* ---------- 使用提示 ---------- */
.notice {
  display: flex;
  gap: 20px;
  padding: 32px 34px;
  border-radius: 20px;
  border: 1px solid var(--line);
  background: var(--surface);
}
.notice__icon {
  flex: none;
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: rgba(169, 87, 79, 0.1);
  color: var(--no);
  border: 1px solid rgba(169, 87, 79, 0.22);
}
html[data-theme="dark"] .notice__icon {
  background: rgba(224, 149, 140, 0.12);
  border-color: rgba(224, 149, 140, 0.24);
}
.notice__icon svg { width: 22px; height: 22px; }
.notice h2 { font-size: 20px; margin-bottom: 10px; }
.notice__body p {
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-2);
}
.notice__body p + p { margin-top: 10px; }
.notice__body strong { color: var(--text); }
.notice__small { font-size: 13px !important; color: var(--text-3) !important; }

/* ---------- 页脚 ---------- */
.footer {
  border-top: 1px solid var(--line);
  background: var(--bg-soft);
  padding: 46px 0 30px;
  position: relative;
  z-index: 1;
}
.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  flex-wrap: wrap;
}
.footer__brand {
  display: flex;
  align-items: center;
  gap: 12px;
}
.footer__brand img { width: 40px; height: 40px; border-radius: 12px; }
.footer__brand strong { font-size: 15.5px; }
.footer__brand p { font-size: 12.5px; color: var(--text-3); margin-top: 1px; }

.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
  font-size: 13.5px;
}
.footer__links a { color: var(--text-2); }
.footer__links a:hover { color: var(--accent); }

.footer__bottom {
  margin-top: 30px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  gap: 12px 24px;
  flex-wrap: wrap;
  font-size: 12px;
  color: var(--text-3);
}

/* ---------- 入场动画（仅在脚本可用时启用，避免脚本失效导致内容不可见） ---------- */
.reveal {
  transition: opacity 0.7s cubic-bezier(0.2, 0.7, 0.2, 1),
    transform 0.7s cubic-bezier(0.2, 0.7, 0.2, 1);
}
.has-js .reveal {
  opacity: 0;
  transform: translateY(16px);
  will-change: opacity, transform;
}
.has-js .reveal.is-in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .hero__inner { gap: 36px; }
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .float-card--1 { left: -6px; }
  .float-card--2 { right: -6px; }
}

@media (max-width: 900px) {
  .hero { padding-top: 48px; }
  .hero__inner { grid-template-columns: minmax(0, 1fr); gap: 48px; }
  .hero__copy { max-width: 640px; }
  .hero__visual { padding-top: 0; }
  .float-card--1 { left: 4%; }
  .float-card--2 { right: 4%; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--3 > :first-child { grid-column: 1 / -1; }
  .steps { grid-template-columns: minmax(0, 1fr); }
  .reasons { grid-template-columns: minmax(0, 1fr); }
  .section { padding: 76px 0; }
}

@media (max-width: 820px) {
  .nav__links { display: none; }
  .nav__inner { justify-content: space-between; gap: 12px; }
}

@media (max-width: 720px) {
  .container { padding: 0 20px; }
  .nav__inner { padding: 10px 20px; }
  .nav__actions { gap: 8px; }
  .brand__ver { display: none; }
  .theme-switch button span { display: none; }
  .theme-switch button { padding: 8px 9px; }

  .hero { padding: 36px 0 60px; }
  .hero h1 { font-size: clamp(32px, 8.4vw, 42px); }
  .hero__lead { font-size: 15.5px; }
  .hero__cta { gap: 10px; }
  .hero__cta .btn { flex: 1 1 100%; }
  .hero__meta { font-size: 12.5px; gap: 8px; }
  .float-card { display: none; }

  .strip__inner { grid-template-columns: 1fr 1fr; gap: 16px 8px; padding: 20px; }
  .strip__item + .strip__item::before { display: none; }
  .strip__item:nth-child(n + 3) { padding-top: 4px; }

  .grid--3,
  .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .grid--3 > :first-child { grid-column: auto; }

  .boundary { grid-template-columns: minmax(0, 1fr); }
  .boundary__col + .boundary__col {
    border-left: 0;
    border-top: 1px solid var(--line);
  }
  .boundary__col { padding: 26px 22px; }

  .section { padding: 64px 0; }
  .section--tight { padding-bottom: 60px; }
  .section__head { margin-bottom: 32px; }

  .card { padding: 24px; }
  .reason { padding: 26px 24px; }
  .limits { padding: 24px 22px; }
  .specs { padding: 22px; }
  .specs__list > div { grid-template-columns: minmax(0, 1fr); gap: 2px; }

  .download__panel { padding: 40px 20px 28px; border-radius: 22px; }
  .download__actions { grid-template-columns: minmax(0, 1fr); margin-top: 24px; }
  .download__links { gap: 6px 12px; font-size: 13px; }

  .notice { flex-direction: column; padding: 24px; gap: 14px; }
  .footer { padding: 36px 0 24px; }
  .footer__bottom { flex-direction: column; gap: 6px; }
  .faq__body { padding-right: 12px; }
}

@media (max-width: 400px) {
  .container { padding: 0 16px; }
  .nav__inner { padding: 10px 14px; gap: 8px; }
  .nav__actions { gap: 6px; }
  .brand img { width: 30px; height: 30px; }
  .brand__name { font-size: 16px; }
  .brand { gap: 7px; }
  .theme-switch { padding: 2px; }
  .theme-switch button { padding: 7px 7px; }
  .btn--sm { padding: 8px 12px; }
  .hero { padding-top: 28px; }
  .hero__meta { font-size: 12px; gap: 7px; }
  .float-card { padding: 8px 10px; font-size: 11.5px; }
  .float-card__k { font-size: 13px; }
  .device__ball { width: 44px; height: 44px; right: 14px; }
}

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