/*
Theme Name: QuickQ Borealis
Theme URI: https://quickqvpn.example.com/borealis
Author: QuickQ Borealis Studio
Author URI: https://quickqvpn.example.com
Description: Privacy-first, conversion-optimized WordPress theme for global VPN, cross-border SaaS and online-security brands. The "Arctic Beam" palette layers electric indigo, glacier violet aurora and mint cryo accents on a frost-white canvas — engineered for high-CTR landing pages with @graph-nested JSON-LD, hreflang, bilingual meta hooks, prefetch-on-intent and Core Web Vitals friendly defaults.
Version: 7.0.0
Requires at least: 6.2
Tested up to: 6.7
Requires PHP: 7.4
License: GPLv2 or later
License URI: https://www.gnu.org/licenses/gpl-2.0.html
Text Domain: qq-borealis
Tags: blog, landing-page, vpn, saas, privacy, blue, light, accessibility-ready
*/

/* =============================================================================
   00 · Arctic Beam — design tokens
   ----------------------------------------------------------------------
   蓝色仍为主导，但氛围由「海色破晓（暖米白 + 珊瑚晨曦 + 阳光琥珀）」
   切换为「极光寒蓝（霜雪白 + 电光靛蓝 + 紫罗极光 + 薄荷冰晶）」——
   底色由暖米奶白转为冷调冰霜白；主轴由偏暖钴蓝深化为更高对比度的电光靛蓝；
   原珊瑚粉/琥珀金双辅色被紫罗极光/薄荷冰晶替代，
   形成「冷调主轴 + 冷调辅助 + 微暖中性」三段式——整体更纯净、更具科技感。
   ============================================================================= */

:root {
  /* —— surfaces · 冰霜白 —— */
  --qb-bg:           #f4f7fb;
  --qb-bg-alt:       #e7eef9;
  --qb-surface:      #ffffff;
  --qb-surface-soft: #f8fafd;
  --qb-surface-deep: #0b1a3d;

  /* —— ink / typography · 深海靛 —— */
  --qb-ink:        #0f1f44;
  --qb-ink-soft:   #1e3050;
  --qb-text:       #2a3a58;
  --qb-text-soft:  #5d6b8a;
  --qb-text-faint: #94a3c4;

  /* —— brand · 电光靛蓝主轴（蓝色保留但偏向 indigo-electric）—— */
  --qb-primary:        #2563eb;
  --qb-primary-strong: #1d4ed8;
  --qb-primary-soft:   #dbeafe;
  --qb-primary-deep:   #1e3a8a;
  --qb-secondary:      #60a5fa;
  --qb-azure:          #38bdf8;

  /* —— accent · 紫罗极光（替代原珊瑚晨曦，整体调性转冷）—— */
  --qb-violet:         #7c3aed;
  --qb-violet-strong:  #6d28d9;
  --qb-violet-soft:    #ede9fe;

  /* —— accent · 薄荷冰晶（替代原阳光琥珀，强化"极地"冷调）—— */
  --qb-mint:           #14b8a6;
  --qb-mint-strong:    #0d9488;
  --qb-mint-soft:      #ccfbf1;

  /* —— signal · 整体语义色 —— */
  --qb-success: #16a34a;
  --qb-warn:    #f59e0b;
  --qb-danger:  #ef4444;

  /* —— borders & shadows · 冷色阴影 —— */
  --qb-border:        #dbe3f0;
  --qb-border-strong: #b6c2dc;
  --qb-shadow-xs: 0 1px 2px rgba(15, 31, 68, 0.05);
  --qb-shadow-sm: 0 2px 14px rgba(15, 31, 68, 0.08);
  --qb-shadow:    0 18px 44px rgba(15, 31, 68, 0.13);
  --qb-shadow-lg: 0 36px 80px rgba(11, 26, 61, 0.22);
  --qb-glow:      0 0 0 6px rgba(37, 99, 235, 0.12),
                  0 14px 32px rgba(124, 58, 237, 0.26);
  --qb-glow-mint: 0 0 0 6px rgba(37, 99, 235, 0.12),
                  0 14px 32px rgba(20, 184, 166, 0.28);

  /* —— hero · 极光寒蓝渐变（关键差异点）—— */
  --qb-hero-grad:
    radial-gradient(ellipse 70% 80% at 84% 14%, rgba(124, 58, 237, 0.46), transparent 52%),
    radial-gradient(circle at 14% 88%, rgba(20, 184, 166, 0.34), transparent 55%),
    linear-gradient(160deg, #0b1a3d 0%, #1e3a8a 28%, #1d4ed8 56%, #2563eb 84%, #3b82f6 100%);
  --qb-aurora-violet: radial-gradient(circle, rgba(124, 58, 237, 0.55), transparent 65%);
  --qb-aurora-mint:   radial-gradient(circle, rgba(20, 184, 166, 0.50), transparent 65%);

  /* —— radius scale · 比旧主题略大，更柔和 —— */
  --qb-radius-xs: 8px;
  --qb-radius-sm: 12px;
  --qb-radius:    18px;
  --qb-radius-lg: 26px;
  --qb-radius-xl: 36px;
  --qb-pill:      999px;

  /* —— layout —— */
  --qb-container: 1180px;
  --qb-gutter:    24px;

  /* —— motion —— */
  --qb-ease:     cubic-bezier(0.32, 0.72, 0, 1);
  --qb-ease-out: cubic-bezier(0.2, 0.9, 0.3, 1);
  --qb-tx-xs:    0.18s var(--qb-ease);
  --qb-tx-sm:    0.26s var(--qb-ease);
  --qb-tx-md:    0.42s var(--qb-ease);
  --qb-tx-lg:    0.72s var(--qb-ease-out);

  /* —— typography —— */
  --qb-font:
    -apple-system, BlinkMacSystemFont, "Segoe UI Variable", "Segoe UI", Inter,
    Roboto, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
    Helvetica, Arial, sans-serif;
  --qb-font-mono:
    "JetBrains Mono", "Cascadia Code", ui-monospace, "SFMono-Regular",
    "Roboto Mono", monospace;
}

/* =============================================================================
   01 · Reset & base
   ============================================================================= */

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

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

body {
  margin: 0;
  font-family: var(--qb-font);
  font-size: 16px;
  color: var(--qb-text);
  background: var(--qb-bg);
  /* 极光寒蓝微光：右上紫罗极光、左上电光靛、底部薄荷冷雾 */
  background-image:
    radial-gradient(circle at 96% -4%,  rgba(124, 58, 237, 0.10), transparent 42%),
    radial-gradient(circle at 4% 6%,    rgba(37, 99, 235, 0.08),  transparent 40%),
    radial-gradient(circle at 50% 108%, rgba(20, 184, 166, 0.10), transparent 50%);
  background-attachment: fixed;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.qb-no-scroll { overflow: hidden; }

a { color: inherit; text-decoration: none; }
a[role="link"] { cursor: pointer; }

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

button { font-family: inherit; }

::selection {
  background: var(--qb-violet);
  color: #fff;
}

:focus-visible {
  outline: 3px solid var(--qb-mint);
  outline-offset: 2px;
}

/* =============================================================================
   02 · Layout primitives
   ============================================================================= */

.qb-shell {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: clip;
}

.qb-container {
  width: min(92%, var(--qb-container));
  margin-inline: auto;
}

.qb-main { flex: 1; }

.qb-section { padding: 96px 0; }
.qb-section--tight { padding-top: 32px; }
.qb-section--alt {
  position: relative;
  background:
    linear-gradient(180deg, rgba(37, 99, 235, 0.05), transparent 55%),
    linear-gradient(180deg, rgba(124, 58, 237, 0.05), transparent 85%);
}

.qb-section-head {
  text-align: center;
  max-width: 820px;
  margin: 0 auto 50px;
}

/* eyebrow · 电光靛软底 + 紫罗极光渐变线 */
.qb-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--qb-primary-strong);
  background: linear-gradient(90deg, var(--qb-primary-soft), #fff 70%);
  border: 1px solid rgba(37, 99, 235, 0.20);
  border-radius: var(--qb-pill);
  padding: 7px 16px 7px 10px;
  margin: 0 0 16px;
}

.qb-eyebrow::before {
  content: "";
  width: 14px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--qb-primary), var(--qb-violet));
  box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.18);
}

.qb-section-head h2 {
  margin: 0 0 14px;
  font-size: clamp(1.65rem, 3.2vw, 2.4rem);
  letter-spacing: -0.01em;
  color: var(--qb-ink);
  line-height: 1.22;
}

.qb-section-head p {
  margin: 0;
  color: var(--qb-text-soft);
  font-size: 1.04rem;
}

/* 渐变文字 · 电光靛 → 紫罗极光 → 薄荷冰晶（冷调三段过渡）*/
.qb-gradient-text {
  background: linear-gradient(95deg, var(--qb-primary) 12%, var(--qb-violet) 55%, var(--qb-mint));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* —— 屏幕阅读器专用文本 —— */
.qb-sr {
  position: absolute !important;
  clip: rect(1px, 1px, 1px, 1px);
  width: 1px;
  height: 1px;
  overflow: hidden;
  white-space: nowrap;
}

/* —— 跳过到主内容 · a11y —— */
.qb-skip {
  position: absolute;
  top: -40px;
  left: 12px;
  background: var(--qb-primary);
  color: #fff;
  padding: 10px 16px;
  border-radius: var(--qb-radius-sm);
  z-index: 999;
  transition: top 0.2s var(--qb-ease);
}

.qb-skip:focus { top: 12px; }

/* =============================================================================
   03 · Header & Navigation
   ============================================================================= */

.qb-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(244, 247, 251, 0.78);
  backdrop-filter: blur(18px) saturate(170%);
  -webkit-backdrop-filter: blur(18px) saturate(170%);
  border-bottom: 1px solid transparent;
  transition: border-color var(--qb-tx-xs), box-shadow var(--qb-tx-xs),
              background var(--qb-tx-xs);
}

.qb-header.is-pinned {
  border-bottom-color: rgba(37, 99, 235, 0.16);
  box-shadow: var(--qb-shadow-sm);
  background: rgba(255, 255, 255, 0.96);
}

.qb-header__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  min-height: 74px;
}

.qb-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.1rem;
  white-space: nowrap;
  color: var(--qb-ink);
}

/* logo 容器 · 深海靛蓝 + 右上紫罗极光 + 左下薄荷冰雾 */
.qb-brand__mark {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  border-radius: 12px;
  background: linear-gradient(150deg, #0b1a3d 0%, #1e3a8a 50%, #1d4ed8 100%);
  padding: 7px;
  display: grid;
  place-items: center;
  box-shadow: 0 8px 22px rgba(37, 99, 235, 0.34);
  position: relative;
  overflow: hidden;
}

.qb-brand__mark::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 80% 20%, rgba(124, 58, 237, 0.55), transparent 55%),
    radial-gradient(circle at 20% 78%, rgba(20, 184, 166, 0.45), transparent 55%);
  pointer-events: none;
}

.qb-brand__mark img,
.qb-brand__mark svg {
  width: 100%;
  height: 100%;
  position: relative;
  z-index: 1;
}

.qb-brand__name {
  background: linear-gradient(95deg, var(--qb-ink) 30%, var(--qb-primary) 65%, var(--qb-violet));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.qb-nav { display: flex; }

.qb-nav ul,
.qb-mobile-nav ul {
  display: flex;
  gap: 4px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.qb-nav a {
  display: inline-flex;
  align-items: center;
  color: var(--qb-text-soft);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 9px 14px;
  border-radius: var(--qb-radius-sm);
  transition: color var(--qb-tx-xs), background var(--qb-tx-xs);
  position: relative;
}

.qb-nav a:hover,
.qb-nav a:focus-visible,
.qb-nav a[aria-current] {
  color: var(--qb-primary-strong);
  background: var(--qb-primary-soft);
}

/* 当前页指示：底部 2px 紫罗极光 → 薄荷冰晶渐变线 */
.qb-nav a[aria-current]::after {
  content: "";
  position: absolute;
  left: 14px; right: 14px; bottom: 4px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--qb-violet), var(--qb-mint));
}

.qb-header__actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.qb-menu-toggle {
  display: none;
  border: 1px solid var(--qb-border);
  background: var(--qb-surface);
  color: var(--qb-ink);
  border-radius: var(--qb-radius-sm);
  font-weight: 600;
  padding: 9px 14px;
  cursor: pointer;
  transition: background var(--qb-tx-xs), border-color var(--qb-tx-xs);
}

.qb-menu-toggle:hover {
  background: var(--qb-primary-soft);
  border-color: var(--qb-primary);
}

/* —— 移动端抽屉 —— */
.qb-mobile-overlay {
  position: fixed;
  inset: 0;
  z-index: 110;
  background: rgba(11, 26, 61, 0.55);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--qb-tx-md);
  backdrop-filter: blur(4px);
}

.qb-mobile-overlay.is-shown {
  opacity: 1;
  pointer-events: auto;
}

.qb-mobile-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: min(82vw, 380px);
  height: 100vh;
  z-index: 120;
  background: var(--qb-surface);
  border-left: 1px solid var(--qb-border);
  box-shadow: -28px 0 70px rgba(11, 26, 61, 0.3);
  transform: translate3d(108%, 0, 0);
  visibility: hidden;
  pointer-events: none;
  will-change: transform;
  transition: transform 0.46s var(--qb-ease),
              visibility 0s linear 0.46s;
  padding: 22px 0;
  touch-action: pan-y;
}

.qb-mobile-panel.is-shown {
  transform: translate3d(0, 0, 0);
  visibility: visible;
  pointer-events: auto;
  transition: transform 0.46s var(--qb-ease),
              visibility 0s linear 0s;
}

.qb-mobile-panel__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.qb-mobile-close {
  width: 38px;
  height: 38px;
  border-radius: var(--qb-radius-sm);
  border: 1px solid var(--qb-border);
  background: var(--qb-surface);
  color: var(--qb-ink);
  font-size: 1.2rem;
  cursor: pointer;
}

.qb-mobile-nav ul {
  flex-direction: column;
  gap: 8px;
}

.qb-mobile-nav a {
  display: block;
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius-sm);
  padding: 13px 15px;
  color: var(--qb-text);
  font-weight: 500;
  transition: background var(--qb-tx-xs), border-color var(--qb-tx-xs);
}

.qb-mobile-nav a:hover {
  background: var(--qb-primary-soft);
  border-color: var(--qb-primary);
  color: var(--qb-primary-strong);
}

.qb-mobile-cta {
  display: flex;
  width: 100%;
  margin-top: 18px;
}

/* =============================================================================
   04 · Buttons（电光靛主轴 + 紫罗极光强调按钮 + 薄荷冰晶光晕）
   ============================================================================= */

.qb-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border-radius: var(--qb-radius-sm);
  border: 1px solid transparent;
  padding: 13px 24px;
  font-weight: 600;
  font-size: 0.97rem;
  letter-spacing: 0.01em;
  transition: transform var(--qb-tx-xs), background var(--qb-tx-xs),
              color var(--qb-tx-xs), border-color var(--qb-tx-xs),
              box-shadow var(--qb-tx-xs);
  cursor: pointer;
  text-align: center;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
  isolation: isolate;
}

.qb-btn:focus-visible {
  outline: 3px solid var(--qb-mint);
  outline-offset: 2px;
}

/* 主按钮 · 电光靛 → 深海靛；hover 露出右下紫罗极光 */
.qb-btn--primary {
  background: linear-gradient(135deg, var(--qb-primary) 0%, var(--qb-primary-strong) 100%);
  color: #fff;
  box-shadow: 0 10px 26px rgba(37, 99, 235, 0.38);
}

.qb-btn--primary::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--qb-primary-strong) 0%, var(--qb-primary-deep) 100%);
  opacity: 0;
  transition: opacity var(--qb-tx-xs);
  z-index: -1;
}

.qb-btn--primary::after {
  content: "";
  position: absolute;
  width: 80%;
  height: 220%;
  right: -25%;
  bottom: -140%;
  background: radial-gradient(ellipse, rgba(124, 58, 237, 0.55), transparent 70%);
  opacity: 0;
  transition: opacity var(--qb-tx-md), transform var(--qb-tx-md);
  z-index: -1;
}

.qb-btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 36px rgba(37, 99, 235, 0.44),
              0 8px 22px rgba(124, 58, 237, 0.32);
}

.qb-btn--primary:hover::before { opacity: 1; }
.qb-btn--primary:hover::after  { opacity: 1; transform: translate(-18%, -12%); }

/* 紫罗极光强调按钮 · 用于二级强 CTA */
.qb-btn--violet {
  background: linear-gradient(135deg, var(--qb-violet) 0%, var(--qb-violet-strong) 100%);
  color: #fff;
  box-shadow: 0 10px 26px rgba(124, 58, 237, 0.38);
}

.qb-btn--violet:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 36px rgba(124, 58, 237, 0.48);
  filter: brightness(1.04);
}

/* 幽灵按钮 · 描边 + hover 电光靛填充 */
.qb-btn--ghost {
  background: var(--qb-surface);
  color: var(--qb-ink);
  border-color: var(--qb-border);
}

.qb-btn--ghost:hover {
  border-color: var(--qb-primary);
  color: var(--qb-primary-strong);
  background: var(--qb-primary-soft);
  transform: translateY(-1px);
}

/* 暗底反白按钮 · hero 内使用 */
.qb-btn--on-dark {
  background: rgba(255, 255, 255, 0.10);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.32);
  backdrop-filter: blur(6px);
}

.qb-btn--on-dark:hover {
  background: #fff;
  color: var(--qb-primary-strong);
}

.qb-btn--inverted {
  background: #fff;
  color: var(--qb-primary-strong);
}

.qb-btn--inverted:hover {
  background: var(--qb-violet-soft);
  color: var(--qb-violet-strong);
}

.qb-btn--lg {
  padding: 15px 30px;
  font-size: 1.02rem;
  border-radius: var(--qb-radius);
}

/* =============================================================================
   05 · Hero — 极光寒蓝面板
   ============================================================================= */

.qb-hero { padding: 56px 0 36px; }

.qb-hero__panel {
  position: relative;
  border-radius: var(--qb-radius-xl);
  padding: 72px 60px;
  background: var(--qb-hero-grad);
  color: #fff;
  overflow: hidden;
  box-shadow: var(--qb-shadow-lg);
  isolation: isolate;
}

/* hero 背景：极夜星空 + 经线条纹 */
.qb-hero__panel::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(1.2px 1.2px at 14% 22%,   rgba(255,255,255,0.85), transparent),
    radial-gradient(1px 1px   at 76% 18%,     rgba(255,255,255,0.65), transparent),
    radial-gradient(1.4px 1.4px at 36% 64%,   rgba(255,255,255,0.80), transparent),
    radial-gradient(1px 1px   at 62% 78%,     rgba(255,255,255,0.55), transparent),
    radial-gradient(1.6px 1.6px at 88% 48%,   rgba(255,255,255,0.85), transparent),
    radial-gradient(1px 1px   at 22% 86%,     rgba(255,255,255,0.50), transparent),
    repeating-linear-gradient(
      115deg,
      rgba(255, 255, 255, 0.035) 0,
      rgba(255, 255, 255, 0.035) 1px,
      transparent 1px,
      transparent 44px
    );
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), rgba(0, 0, 0, 0.5));
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), rgba(0, 0, 0, 0.5));
  pointer-events: none;
}

/* hero 右上"紫罗极光"光斑 */
.qb-hero__panel::after {
  content: "";
  position: absolute;
  width: 620px;
  height: 620px;
  right: -180px;
  top: -260px;
  border-radius: 50%;
  background: var(--qb-aurora-violet);
  pointer-events: none;
  z-index: 0;
}

/* hero 左下"薄荷冰晶"光斑（与极光形成对角张力） */
.qb-hero__panel > .qb-glow-mint {
  position: absolute;
  width: 380px;
  height: 380px;
  left: -130px;
  bottom: -140px;
  border-radius: 50%;
  background: var(--qb-aurora-mint);
  pointer-events: none;
  z-index: 0;
}

/* hero 右上"北极星"光痕（替代旧主题的"晨星"）*/
.qb-hero__panel > .qb-polestar {
  position: absolute;
  width: 110px;
  height: 110px;
  right: 8%;
  top: 14%;
  pointer-events: none;
  z-index: 0;
  opacity: 0.9;
}

.qb-hero__panel > .qb-polestar::before,
.qb-hero__panel > .qb-polestar::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255, 255, 255, 0.85) 50%, transparent 100%);
  filter: blur(0.4px);
}

.qb-hero__panel > .qb-polestar::before {
  height: 1.5px;
  top: 50%;
  transform: translateY(-50%);
  box-shadow: 0 0 10px rgba(124, 58, 237, 0.85);
  animation: qbStarHorz 2.6s ease-in-out infinite;
}

.qb-hero__panel > .qb-polestar::after {
  width: 1.5px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(180deg, transparent 0%, rgba(255, 255, 255, 0.85) 50%, transparent 100%);
  box-shadow: 0 0 10px rgba(20, 184, 166, 0.85);
  animation: qbStarVert 2.6s ease-in-out infinite;
}

@keyframes qbStarHorz {
  0%, 100% { opacity: 0.6; transform: translateY(-50%) scaleX(1);   }
  50%      { opacity: 1;   transform: translateY(-50%) scaleX(1.4); }
}

@keyframes qbStarVert {
  0%, 100% { opacity: 0.6; transform: translateX(-50%) scaleY(1);   }
  50%      { opacity: 1;   transform: translateX(-50%) scaleY(1.4); }
}

.qb-hero__grid {
  position: relative;
  display: grid;
  gap: 44px;
  grid-template-columns: 1.15fr 1fr;
  align-items: center;
  z-index: 1;
}

.qb-hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #c4b5fd;
  border: 1px solid rgba(255, 255, 255, 0.30);
  border-radius: var(--qb-pill);
  padding: 7px 16px 7px 12px;
  margin: 0 0 22px;
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(6px);
}

.qb-hero__eyebrow::before {
  content: "";
  width: 14px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--qb-violet), var(--qb-mint));
  box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.30);
}

.qb-hero__title {
  margin: 0 0 20px;
  font-size: clamp(2.1rem, 4.8vw, 3.3rem);
  line-height: 1.14;
  letter-spacing: -0.025em;
  font-weight: 800;
}

/* 高亮词 · 紫罗极光 → 薄荷冰晶（冷调反相）*/
.qb-hero__title em {
  font-style: normal;
  background: linear-gradient(95deg, #c4b5fd 0%, #a78bfa 30%, #5eead4 80%, #ffffff 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.qb-hero__lead {
  margin: 0 0 32px;
  color: rgba(255, 255, 255, 0.86);
  font-size: 1.08rem;
  max-width: 560px;
  line-height: 1.7;
}

.qb-hero__cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.qb-hero__chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.qb-hero__chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--qb-pill);
  padding: 8px 14px;
  font-size: 0.86rem;
  color: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(4px);
}

.qb-hero__chip::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--qb-mint);
  box-shadow: 0 0 0 4px rgba(20, 184, 166, 0.30);
}

/* hero 右侧实时面板 · 毛玻璃 + 电光靛→紫罗→薄荷渐变描边 */
.qb-hero__widget {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(10px);
  border-radius: var(--qb-radius);
  padding: 24px;
  position: relative;
  overflow: hidden;
}

.qb-hero__widget::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg,
    rgba(37, 99, 235, 0.55) 0%,
    rgba(124, 58, 237, 0.60) 50%,
    rgba(20, 184, 166, 0.55) 100%);
  -webkit-mask:
    linear-gradient(#fff 0 0) content-box,
    linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.qb-hero__widget h2 {
  margin: 0 0 18px;
  font-size: 1.08rem;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.qb-hero__widget h2::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--qb-mint);
  box-shadow: 0 0 0 4px rgba(20, 184, 166, 0.32);
  animation: qbPulse 1.8s ease-in-out infinite;
}

@keyframes qbPulse {
  0%, 100% { transform: scale(1);    opacity: 1;    }
  50%      { transform: scale(1.35); opacity: 0.55; }
}

.qb-metric-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.qb-metric {
  border-radius: var(--qb-radius-sm);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  padding: 14px 16px;
}

.qb-metric small {
  display: block;
  color: rgba(255, 255, 255, 0.74);
  font-size: 0.8rem;
  margin-bottom: 4px;
}

.qb-metric strong {
  display: block;
  font-size: 1.32rem;
  color: #fff;
  font-weight: 800;
}

/* =============================================================================
   06 · Trust strip / 数据条
   ============================================================================= */

.qb-stats-strip { padding: 40px 0 16px; }

.qb-stats-strip__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.qb-stat-tile {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 22px 22px;
  text-align: center;
  box-shadow: var(--qb-shadow-sm);
  position: relative;
  overflow: hidden;
  transition: transform var(--qb-tx-sm), box-shadow var(--qb-tx-sm);
}

/* 悬停下方升起一根 电光靛→紫罗→薄荷 冷调极光线 */
.qb-stat-tile::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  height: 3px;
  width: 0;
  border-radius: 3px 3px 0 0;
  background: linear-gradient(90deg, var(--qb-primary), var(--qb-violet), var(--qb-mint));
  transition: width var(--qb-tx-md), left var(--qb-tx-md);
}

.qb-stat-tile:hover {
  transform: translateY(-3px);
  box-shadow: var(--qb-shadow);
}

.qb-stat-tile:hover::after {
  width: 70%;
  left: 15%;
}

.qb-stat-tile strong {
  display: block;
  font-size: 1.45rem;
  color: var(--qb-ink);
  font-weight: 800;
  letter-spacing: -0.01em;
}

.qb-stat-tile span {
  color: var(--qb-text-soft);
  font-size: 0.88rem;
}

/* =============================================================================
   07 · Card grids（功能 / 场景 / 帮助 / FAQ / 博客）
   ============================================================================= */

.qb-card-grid {
  display: grid;
  gap: 22px;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.qb-cap-card,
.qb-download-card,
.qb-plan-card,
.qb-faq-item,
.qb-blog-card,
.qb-help-card {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  box-shadow: var(--qb-shadow-xs);
  transition: transform var(--qb-tx-md), border-color var(--qb-tx-xs),
              box-shadow var(--qb-tx-md);
}

.qb-cap-card {
  padding: 28px 26px;
  position: relative;
  overflow: hidden;
}

/* 卡片 hover 左侧探出 3px 电光靛→紫罗→薄荷渐变线 */
.qb-cap-card::before {
  content: "";
  position: absolute;
  top: 16px;
  bottom: 16px;
  left: 0;
  width: 3px;
  border-radius: 0 3px 3px 0;
  background: linear-gradient(180deg, var(--qb-primary), var(--qb-violet), var(--qb-mint));
  transform: scaleY(0.2);
  transform-origin: top;
  opacity: 0;
  transition: transform var(--qb-tx-md), opacity var(--qb-tx-md);
}

.qb-cap-card:hover {
  transform: translateY(-4px);
  border-color: rgba(37, 99, 235, 0.30);
  box-shadow: var(--qb-shadow);
}

.qb-cap-card:hover::before {
  transform: scaleY(1);
  opacity: 1;
}

.qb-cap-card__icon {
  display: inline-grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-violet-soft));
  font-size: 1.4rem;
  margin-bottom: 18px;
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.16);
}

.qb-cap-card h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
  color: var(--qb-ink);
}

.qb-cap-card p {
  margin: 0;
  color: var(--qb-text-soft);
  font-size: 0.94rem;
  line-height: 1.65;
}

/* =============================================================================
   08 · Plan cards / 订阅套餐 / 计费切换
   ============================================================================= */

.qb-billing-switch {
  display: inline-flex;
  align-items: center;
  margin: 0 auto 38px;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-pill);
  padding: 4px;
  gap: 4px;
  box-shadow: var(--qb-shadow-xs);
}

.qb-billing-switch button {
  border: 0;
  background: transparent;
  border-radius: var(--qb-pill);
  padding: 9px 18px;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--qb-text-soft);
  cursor: pointer;
  transition: background var(--qb-tx-xs), color var(--qb-tx-xs);
}

.qb-billing-switch button.is-active {
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
  color: #fff;
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.30);
}

.qb-plans {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  align-items: stretch;
}

.qb-plan-card {
  padding: 30px 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  position: relative;
}

.qb-plan-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--qb-shadow);
  border-color: rgba(37, 99, 235, 0.30);
}

.qb-plan-card__head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.qb-plan-card h3 {
  margin: 0;
  font-size: 1.15rem;
  color: var(--qb-ink);
}

.qb-plan-card__note {
  margin: 0;
  color: var(--qb-text-soft);
  font-size: 0.92rem;
  min-height: 38px;
}

.qb-plan-card__price {
  margin: 6px 0 14px;
  font-weight: 800;
  font-size: 2.05rem;
  color: var(--qb-ink);
  letter-spacing: -0.02em;
}

.qb-plan-card__price span {
  font-size: 0.96rem;
  font-weight: 500;
  color: var(--qb-text-soft);
  margin-left: 6px;
}

.qb-plan-card ul {
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  flex: 1;
  display: grid;
  gap: 10px;
}

.qb-plan-card li {
  position: relative;
  padding-left: 24px;
  font-size: 0.94rem;
  color: var(--qb-text);
}

.qb-plan-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-mint-soft));
  border: 1.6px solid var(--qb-primary);
}

.qb-plan-card li::after {
  content: "";
  position: absolute;
  left: 4px;
  top: 9px;
  width: 6px;
  height: 3px;
  border-left: 1.6px solid var(--qb-primary);
  border-bottom: 1.6px solid var(--qb-primary);
  transform: rotate(-45deg);
}

.qb-plan-card .qb-btn {
  width: 100%;
}

.qb-plan-badge {
  display: inline-flex;
  align-items: center;
  background: var(--qb-bg-alt);
  color: var(--qb-text-soft);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  padding: 4px 10px;
  border-radius: var(--qb-pill);
  text-transform: uppercase;
}

.qb-plan-badge--accent {
  background: linear-gradient(135deg, var(--qb-violet), var(--qb-primary));
  color: #fff;
  box-shadow: 0 4px 10px rgba(124, 58, 237, 0.30);
}

/* 推荐套餐 · 渐变描边 + ribbon */
.qb-plan-card--featured {
  border-color: transparent;
  background:
    linear-gradient(var(--qb-surface), var(--qb-surface)) padding-box,
    linear-gradient(140deg, var(--qb-primary), var(--qb-violet) 60%, var(--qb-mint)) border-box;
  border-width: 2px;
  border-style: solid;
  box-shadow: 0 18px 38px rgba(37, 99, 235, 0.20);
}

.qb-plan-card--featured::after {
  content: attr(data-ribbon);
  position: absolute;
  top: -14px;
  right: 22px;
  background: linear-gradient(135deg, var(--qb-violet), var(--qb-primary));
  color: #fff;
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 6px 14px;
  border-radius: var(--qb-pill);
  box-shadow: 0 6px 14px rgba(124, 58, 237, 0.34);
}

/* =============================================================================
   09 · Comparison table
   ============================================================================= */

.qb-compare-wrap {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  overflow: hidden;
  box-shadow: var(--qb-shadow-sm);
  overflow-x: auto;
}

.qb-compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.qb-compare-table thead {
  background: linear-gradient(180deg, var(--qb-primary-soft), transparent);
}

.qb-compare-table th,
.qb-compare-table td {
  padding: 16px 18px;
  text-align: left;
  border-bottom: 1px solid var(--qb-border);
  vertical-align: top;
}

.qb-compare-table thead th {
  font-weight: 700;
  color: var(--qb-ink);
  font-size: 0.95rem;
}

.qb-compare-table tbody th {
  font-weight: 600;
  color: var(--qb-ink);
  background: var(--qb-surface-soft);
  width: 30%;
}

.qb-compare-table tbody tr:last-child th,
.qb-compare-table tbody tr:last-child td {
  border-bottom: 0;
}

/* =============================================================================
   10 · Download cards
   ============================================================================= */

.qb-download-grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.qb-download-card {
  padding: 22px 20px;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 6px;
  color: var(--qb-text);
  position: relative;
  isolation: isolate;
  overflow: hidden;
}

.qb-download-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  background: linear-gradient(135deg,
    rgba(37, 99, 235, 0) 0%,
    rgba(124, 58, 237, 0) 50%,
    rgba(20, 184, 166, 0) 100%);
  z-index: -1;
  transition: background var(--qb-tx-md);
}

.qb-download-card:hover {
  transform: translateY(-3px);
  border-color: rgba(37, 99, 235, 0.35);
  box-shadow: var(--qb-shadow);
}

.qb-download-card:hover::before {
  background: linear-gradient(135deg,
    rgba(37, 99, 235, 0.07) 0%,
    rgba(124, 58, 237, 0.05) 50%,
    rgba(20, 184, 166, 0.07) 100%);
}

.qb-download-card__platform {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--qb-ink);
}

.qb-download-card__hint {
  color: var(--qb-text-soft);
  font-size: 0.86rem;
}

/* =============================================================================
   11 · Testimonials carousel
   ============================================================================= */

.qb-testimonials {
  position: relative;
  overflow: hidden;
  padding: 4px;
}

.qb-testimonials__track {
  display: flex;
  gap: 22px;
  transition: transform var(--qb-tx-md);
}

.qb-testimonial-card {
  flex: 0 0 calc((100% - 44px) / 3);
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 26px 24px;
  box-shadow: var(--qb-shadow-xs);
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.qb-testimonial-card p {
  margin: 0;
  color: var(--qb-text);
  line-height: 1.7;
  font-size: 0.96rem;
}

.qb-testimonial-card strong {
  color: var(--qb-text-soft);
  font-weight: 600;
  font-size: 0.86rem;
}

.qb-carousel-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-top: 22px;
}

.qb-carousel-arrow {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid var(--qb-border);
  background: var(--qb-surface);
  color: var(--qb-ink);
  font-size: 1.1rem;
  cursor: pointer;
  transition: background var(--qb-tx-xs), border-color var(--qb-tx-xs);
}

.qb-carousel-arrow:hover {
  background: var(--qb-primary-soft);
  border-color: var(--qb-primary);
  color: var(--qb-primary-strong);
}

.qb-carousel-dots {
  display: flex;
  gap: 8px;
}

.qb-carousel-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 0;
  padding: 0;
  background: var(--qb-border-strong);
  cursor: pointer;
  transition: background var(--qb-tx-xs), transform var(--qb-tx-xs);
}

.qb-carousel-dot.is-active {
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
  transform: scale(1.25);
}

/* =============================================================================
   12 · Step list（5-step quickstart）
   ============================================================================= */

.qb-step-list {
  list-style: none;
  padding: 0;
}

.qb-step-list li {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 18px 22px;
  box-shadow: var(--qb-shadow-xs);
}

.qb-step-num {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-weight: 800;
  color: #fff;
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.32);
}

.qb-step-list strong {
  color: var(--qb-ink);
}

/* =============================================================================
   13 · FAQ accordion
   ============================================================================= */

.qb-faq {
  display: grid;
  gap: 14px;
  max-width: 880px;
  margin: 0 auto;
}

.qb-faq-item {
  padding: 0;
  overflow: hidden;
  transition: border-color var(--qb-tx-xs), box-shadow var(--qb-tx-xs);
}

.qb-faq-item.is-open {
  border-color: rgba(37, 99, 235, 0.32);
  box-shadow: var(--qb-shadow-sm);
}

.qb-faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  border: 0;
  background: transparent;
  text-align: left;
  cursor: pointer;
  padding: 20px 22px;
  font: inherit;
  font-size: 1rem;
  font-weight: 600;
  color: var(--qb-ink);
  transition: color var(--qb-tx-xs);
}

.qb-faq-question::after {
  content: "+";
  font-size: 1.4rem;
  color: var(--qb-primary);
  transition: transform var(--qb-tx-sm);
}

.qb-faq-item.is-open .qb-faq-question {
  color: var(--qb-primary-strong);
}

.qb-faq-item.is-open .qb-faq-question::after {
  transform: rotate(45deg);
}

.qb-faq-answer {
  padding: 0 22px 22px;
  color: var(--qb-text-soft);
  line-height: 1.7;
  font-size: 0.96rem;
}

.qb-faq-answer p { margin: 0; }

/* =============================================================================
   14 · Blog cards
   ============================================================================= */

.qb-blog-grid {
  display: grid;
  gap: 22px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.qb-blog-archive {
  display: grid;
  gap: 22px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-bottom: 40px;
}

.qb-blog-card {
  padding: 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.qb-blog-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--qb-shadow);
  border-color: rgba(37, 99, 235, 0.30);
}

.qb-blog-card__thumb {
  display: block;
  aspect-ratio: 16 / 9;
  background: var(--qb-bg-alt);
  overflow: hidden;
}

.qb-blog-card__thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--qb-tx-md);
}

.qb-blog-card:hover .qb-blog-card__thumb img {
  transform: scale(1.04);
}

.qb-blog-card__body {
  padding: 22px 22px 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.qb-blog-card__meta {
  margin: 0;
  font-size: 0.82rem;
  color: var(--qb-text-faint);
}

.qb-blog-card__title {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.45;
}

.qb-blog-card__title a {
  color: var(--qb-ink);
  transition: color var(--qb-tx-xs);
}

.qb-blog-card__title a:hover {
  color: var(--qb-primary-strong);
}

.qb-blog-card__excerpt {
  margin: 0;
  color: var(--qb-text-soft);
  font-size: 0.92rem;
  line-height: 1.65;
  flex: 1;
}

.qb-blog-card__link {
  margin-top: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--qb-primary);
  align-self: flex-start;
  transition: color var(--qb-tx-xs);
}

.qb-blog-card__link:hover { color: var(--qb-violet-strong); }

/* =============================================================================
   15 · Tag cloud
   ============================================================================= */

.qb-tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.qb-tag-cloud a {
  display: inline-flex;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  color: var(--qb-text);
  padding: 7px 14px;
  border-radius: var(--qb-pill);
  font-size: 0.88rem;
  transition: background var(--qb-tx-xs), color var(--qb-tx-xs),
              border-color var(--qb-tx-xs);
}

.qb-tag-cloud a:hover {
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-violet-soft));
  border-color: var(--qb-primary);
  color: var(--qb-primary-strong);
}

/* =============================================================================
   16 · CTA strip
   ============================================================================= */

.qb-cta-strip {
  background: var(--qb-hero-grad);
  border-radius: var(--qb-radius-xl);
  padding: 56px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 28px;
  color: #fff;
  position: relative;
  overflow: hidden;
  box-shadow: var(--qb-shadow-lg);
}

.qb-cta-strip::after {
  content: "";
  position: absolute;
  width: 480px;
  height: 480px;
  right: -120px;
  top: -160px;
  border-radius: 50%;
  background: var(--qb-aurora-violet);
  pointer-events: none;
}

.qb-cta-strip > * { position: relative; z-index: 1; }

.qb-cta-strip h2 {
  margin: 0 0 8px;
  font-size: clamp(1.5rem, 2.6vw, 2rem);
  letter-spacing: -0.01em;
}

.qb-cta-strip p {
  margin: 0;
  color: rgba(255, 255, 255, 0.84);
}

.qb-cta-strip__actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* =============================================================================
   17 · Footer
   ============================================================================= */

.qb-footer {
  margin-top: 80px;
  background: linear-gradient(180deg, transparent, rgba(37, 99, 235, 0.04));
  border-top: 1px solid var(--qb-border);
  padding: 60px 0 28px;
  color: var(--qb-text-soft);
}

.qb-footer__inner {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, minmax(0, 1fr));
  gap: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid var(--qb-border);
}

.qb-footer h4 {
  margin: 0 0 16px;
  font-size: 0.92rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--qb-ink);
}

.qb-footer ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 8px;
}

.qb-footer ul a {
  color: var(--qb-text-soft);
  font-size: 0.92rem;
  transition: color var(--qb-tx-xs);
}

.qb-footer ul a:hover { color: var(--qb-primary-strong); }

.qb-footer__brand-text {
  margin: 12px 0 0;
  font-size: 0.92rem;
  line-height: 1.7;
  max-width: 360px;
}

.qb-footer__brand-text a { color: var(--qb-primary-strong); }

.qb-footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.86rem;
  color: var(--qb-text-faint);
  padding-top: 24px;
}

.qb-footer__friends {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.qb-footer__friends a {
  color: var(--qb-primary);
  transition: color var(--qb-tx-xs);
}

.qb-footer__friends a:hover { color: var(--qb-violet-strong); }

/* =============================================================================
   18 · Page banner（用于 blog / help / privacy / terms）
   ============================================================================= */

.qb-page-banner {
  position: relative;
  padding: 96px 0 60px;
  background:
    radial-gradient(ellipse 80% 60% at 80% 10%, rgba(124, 58, 237, 0.18), transparent 55%),
    radial-gradient(ellipse 60% 50% at 12% 90%, rgba(20, 184, 166, 0.15), transparent 55%),
    linear-gradient(180deg, rgba(37, 99, 235, 0.08), transparent 100%);
  border-bottom: 1px solid var(--qb-border);
  text-align: center;
  overflow: hidden;
}

.qb-page-banner h1 {
  margin: 8px auto 14px;
  font-size: clamp(1.7rem, 3.2vw, 2.4rem);
  color: var(--qb-ink);
  max-width: 880px;
  letter-spacing: -0.01em;
  line-height: 1.25;
}

.qb-page-banner p {
  margin: 0 auto;
  max-width: 720px;
  color: var(--qb-text-soft);
  font-size: 1rem;
}

.qb-page-body {
  padding: 60px 0 96px;
}

/* =============================================================================
   19 · Breadcrumb
   ============================================================================= */

.qb-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 0.86rem;
  color: var(--qb-text-soft);
  margin-bottom: 28px;
}

.qb-breadcrumb a {
  color: var(--qb-text-soft);
  transition: color var(--qb-tx-xs);
}

.qb-breadcrumb a:hover { color: var(--qb-primary-strong); }

.qb-breadcrumb__sep { color: var(--qb-text-faint); }

.qb-breadcrumb [aria-current="page"] {
  color: var(--qb-ink);
  font-weight: 600;
}

/* =============================================================================
   20 · Single post
   ============================================================================= */

.qb-single { padding: 48px 0 96px; }

.qb-post-header { margin-bottom: 28px; }

.qb-post-title {
  margin: 0 0 14px;
  font-size: clamp(1.7rem, 3.4vw, 2.6rem);
  color: var(--qb-ink);
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.qb-post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--qb-text-soft);
}

.qb-post-meta a {
  color: var(--qb-primary);
  transition: color var(--qb-tx-xs);
}

.qb-post-meta a:hover { color: var(--qb-violet-strong); }

.qb-post-meta__sep { color: var(--qb-text-faint); }

.qb-read-time {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--qb-primary-soft);
  color: var(--qb-primary-strong);
  padding: 4px 10px;
  border-radius: var(--qb-pill);
  font-size: 0.78rem;
  font-weight: 600;
}

.qb-read-time::before {
  content: "⌛";
  font-size: 0.86rem;
}

/* TL;DR 摘要框 */
.qb-tldr {
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-violet-soft));
  border-left: 4px solid var(--qb-primary);
  border-radius: var(--qb-radius-sm);
  padding: 16px 20px;
  margin: 0 0 28px;
  color: var(--qb-ink-soft);
  line-height: 1.7;
  font-size: 0.96rem;
}

.qb-tldr strong { color: var(--qb-primary-strong); }

.qb-post-thumbnail {
  margin: 0 0 28px;
  border-radius: var(--qb-radius);
  overflow: hidden;
  box-shadow: var(--qb-shadow-sm);
}

.qb-post-featured-image {
  width: 100%;
  height: auto;
  display: block;
}

/* TOC 自动目录 */
.qb-toc {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-left: 4px solid var(--qb-primary);
  border-radius: var(--qb-radius-sm);
  padding: 18px 22px;
  margin: 0 0 32px;
  font-size: 0.94rem;
}

.qb-toc strong {
  display: block;
  margin-bottom: 10px;
  color: var(--qb-ink);
  font-size: 0.95rem;
}

.qb-toc ol {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 6px;
}

.qb-toc a {
  color: var(--qb-text-soft);
  transition: color var(--qb-tx-xs);
}

.qb-toc a:hover { color: var(--qb-primary-strong); }

/* Prose */
.qb-prose,
.qb-post-content {
  color: var(--qb-text);
  line-height: 1.8;
  font-size: 1rem;
  max-width: 760px;
  margin: 0 auto;
}

.qb-prose h2,
.qb-post-content h2 {
  margin: 40px 0 14px;
  color: var(--qb-ink);
  font-size: 1.4rem;
  letter-spacing: -0.005em;
  scroll-margin-top: 90px;
}

.qb-prose h3,
.qb-post-content h3 {
  margin: 28px 0 10px;
  color: var(--qb-ink);
  font-size: 1.16rem;
  scroll-margin-top: 90px;
}

.qb-prose p,
.qb-post-content p {
  margin: 0 0 16px;
}

.qb-prose ul,
.qb-prose ol,
.qb-post-content ul,
.qb-post-content ol {
  padding-left: 22px;
  margin: 0 0 18px;
}

.qb-prose li,
.qb-post-content li { margin: 6px 0; }

.qb-prose code,
.qb-post-content code {
  font-family: var(--qb-font-mono);
  background: var(--qb-bg-alt);
  border: 1px solid var(--qb-border);
  border-radius: 6px;
  padding: 2px 6px;
  font-size: 0.9em;
  color: var(--qb-violet-strong);
}

.qb-prose blockquote,
.qb-post-content blockquote {
  margin: 22px 0;
  padding: 14px 22px;
  border-left: 4px solid var(--qb-violet);
  background: linear-gradient(90deg, var(--qb-violet-soft), transparent 80%);
  color: var(--qb-text);
  font-style: italic;
  border-radius: 0 var(--qb-radius-sm) var(--qb-radius-sm) 0;
}

.qb-prose__callout {
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-mint-soft));
  border: 1px solid rgba(37, 99, 235, 0.18);
  border-radius: var(--qb-radius);
  padding: 18px 22px;
  margin: 0 0 30px;
  color: var(--qb-ink-soft);
  font-size: 0.97rem;
  line-height: 1.7;
}

.qb-bullets {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 8px;
}

.qb-bullets > li {
  position: relative;
  padding-left: 22px;
}

.qb-bullets > li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
}

/* Author bio · E-E-A-T */
.qb-author-bio {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 22px 24px;
  margin: 40px 0 0;
  box-shadow: var(--qb-shadow-xs);
}

.qb-author-bio__mark {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: 1.4rem;
  flex-shrink: 0;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.34);
}

.qb-author-bio__body { flex: 1; }

.qb-author-bio__name {
  display: block;
  color: var(--qb-ink);
  font-size: 1rem;
}

.qb-author-bio__role {
  color: var(--qb-primary-strong);
  font-size: 0.84rem;
  margin-left: 8px;
}

.qb-author-bio__desc {
  margin: 8px 0 0;
  color: var(--qb-text-soft);
  font-size: 0.94rem;
  line-height: 1.7;
}

/* Related posts */
.qb-related {
  margin: 40px 0 0;
}

.qb-related h2 {
  margin: 0 0 16px;
  color: var(--qb-ink);
  font-size: 1.2rem;
}

.qb-related__grid {
  display: grid;
  gap: 14px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.qb-related__item {
  display: block;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius-sm);
  padding: 16px 18px;
  color: var(--qb-ink);
  transition: border-color var(--qb-tx-xs), box-shadow var(--qb-tx-xs),
              transform var(--qb-tx-xs);
  font-weight: 600;
  line-height: 1.5;
  font-size: 0.94rem;
}

.qb-related__item small {
  display: block;
  color: var(--qb-text-faint);
  font-size: 0.78rem;
  font-weight: 500;
  margin-bottom: 4px;
}

.qb-related__item:hover {
  border-color: rgba(37, 99, 235, 0.32);
  box-shadow: var(--qb-shadow-sm);
  transform: translateY(-2px);
}

/* Post navigation · prev / next */
.qb-post-nav {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr 1fr;
  margin-top: 48px;
}

.qb-post-nav__prev,
.qb-post-nav__next {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 16px 20px;
  color: var(--qb-ink);
  transition: border-color var(--qb-tx-xs), box-shadow var(--qb-tx-xs);
}

.qb-post-nav__next { text-align: right; }

.qb-post-nav__prev:hover,
.qb-post-nav__next:hover {
  border-color: rgba(37, 99, 235, 0.32);
  box-shadow: var(--qb-shadow-sm);
}

.qb-post-nav__label {
  display: block;
  font-size: 0.78rem;
  color: var(--qb-primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 4px;
}

.qb-post-nav__title {
  display: block;
  font-weight: 600;
  font-size: 0.95rem;
}

.qb-post-pages {
  margin: 24px 0 0;
  font-size: 0.92rem;
  color: var(--qb-text-soft);
}

.qb-post-pages a {
  display: inline-block;
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  padding: 4px 10px;
  border-radius: var(--qb-radius-sm);
  margin: 0 4px;
  color: var(--qb-text);
}

/* =============================================================================
   21 · Help center grid
   ============================================================================= */

.qb-help-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  margin-bottom: 50px;
}

.qb-help-card {
  padding: 24px 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.qb-help-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--qb-shadow);
  border-color: rgba(37, 99, 235, 0.30);
}

.qb-help-card__icon {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--qb-primary-soft), var(--qb-mint-soft));
  font-size: 1.2rem;
}

.qb-help-card__links {
  list-style: none;
  padding: 0;
  margin: 6px 0 0;
  display: grid;
  gap: 6px;
}

.qb-help-card__links a {
  color: var(--qb-text-soft);
  font-size: 0.9rem;
  transition: color var(--qb-tx-xs);
}

.qb-help-card__links a:hover { color: var(--qb-primary-strong); }

.qb-help-section {
  background: var(--qb-surface);
  border: 1px solid var(--qb-border);
  border-radius: var(--qb-radius);
  padding: 28px 32px;
  margin: 0 0 24px;
  box-shadow: var(--qb-shadow-xs);
  scroll-margin-top: 90px;
}

.qb-help-section h2 {
  margin: 0 0 14px;
  color: var(--qb-ink);
  font-size: 1.3rem;
  letter-spacing: -0.005em;
}

.qb-help-section h3 {
  margin: 24px 0 10px;
  color: var(--qb-ink);
  font-size: 1.05rem;
  scroll-margin-top: 90px;
}

.qb-help-section p {
  margin: 0 0 14px;
  color: var(--qb-text);
  line-height: 1.75;
}

.qb-help-section ul {
  margin: 0 0 16px;
  padding-left: 22px;
  color: var(--qb-text);
}

.qb-help-section li { margin: 6px 0; }

.qb-help-section code {
  font-family: var(--qb-font-mono);
  background: var(--qb-bg-alt);
  border: 1px solid var(--qb-border);
  border-radius: 6px;
  padding: 2px 6px;
  font-size: 0.9em;
  color: var(--qb-violet-strong);
}

/* =============================================================================
   22 · Pagination
   ============================================================================= */

.qb-pagination {
  display: flex;
  justify-content: center;
  margin: 36px 0;
}

.qb-pagination ul {
  list-style: none;
  display: flex;
  gap: 8px;
  padding: 0;
  margin: 0;
  flex-wrap: wrap;
  justify-content: center;
}

.qb-pagination a,
.qb-pagination span {
  display: inline-grid;
  place-items: center;
  min-width: 38px;
  height: 38px;
  padding: 0 12px;
  border-radius: var(--qb-radius-sm);
  border: 1px solid var(--qb-border);
  background: var(--qb-surface);
  color: var(--qb-ink);
  font-weight: 600;
  font-size: 0.92rem;
  transition: background var(--qb-tx-xs), color var(--qb-tx-xs),
              border-color var(--qb-tx-xs);
}

.qb-pagination a:hover {
  background: var(--qb-primary-soft);
  border-color: var(--qb-primary);
  color: var(--qb-primary-strong);
}

.qb-pagination .current {
  background: linear-gradient(135deg, var(--qb-primary), var(--qb-violet));
  color: #fff;
  border-color: transparent;
}

/* =============================================================================
   23 · Responsive
   ============================================================================= */

@media (max-width: 1024px) {
  .qb-card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .qb-plans { grid-template-columns: 1fr; }
  .qb-download-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .qb-blog-grid,
  .qb-blog-archive { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .qb-help-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .qb-related__grid { grid-template-columns: 1fr; }
  .qb-footer__inner { grid-template-columns: 1fr 1fr; }
  .qb-hero__grid { grid-template-columns: 1fr; }
  .qb-hero__panel { padding: 56px 36px; }
  .qb-stats-strip__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .qb-testimonial-card { flex: 0 0 calc((100% - 22px) / 2); }
}

@media (max-width: 768px) {
  .qb-section { padding: 64px 0; }
  .qb-card-grid { grid-template-columns: 1fr; }
  .qb-download-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .qb-blog-grid,
  .qb-blog-archive,
  .qb-help-grid { grid-template-columns: 1fr; }
  .qb-footer__inner { grid-template-columns: 1fr; }
  .qb-nav { display: none; }
  .qb-menu-toggle { display: inline-flex; }
  .qb-hero__panel { padding: 44px 24px; }
  .qb-hero__title { font-size: clamp(1.7rem, 7vw, 2.2rem); }
  .qb-cta-strip { padding: 38px 28px; flex-direction: column; align-items: flex-start; }
  .qb-testimonial-card { flex: 0 0 100%; }
  .qb-post-nav { grid-template-columns: 1fr; }
  .qb-help-section { padding: 22px 20px; }
}

@media (max-width: 480px) {
  .qb-stats-strip__grid { grid-template-columns: 1fr; }
  .qb-billing-switch { width: 100%; }
  .qb-billing-switch button { flex: 1; }
}

/* =============================================================================
   24 · Reveal-on-scroll
   ============================================================================= */

[data-qb-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s var(--qb-ease-out), transform 0.7s var(--qb-ease-out);
}

[data-qb-reveal].is-shown {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  [data-qb-reveal] { opacity: 1; transform: none; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

/* =============================================================================
   25 · Print stylesheet
   ============================================================================= */

@media print {
  .qb-header,
  .qb-footer,
  .qb-mobile-overlay,
  .qb-mobile-panel,
  .qb-cta-strip,
  .qb-related,
  .qb-post-nav,
  .qb-tag-cloud,
  .qb-skip,
  [data-qb-reveal] { display: none !important; opacity: 1 !important; }

  body { background: #fff !important; color: #000 !important; }
  .qb-prose, .qb-post-content { max-width: none !important; }
  a { color: inherit !important; text-decoration: underline !important; }
  a[href]::after { content: " (" attr(href) ")"; font-size: 0.85em; color: #555; }
}