/* 广告页共同样式（配合 style.css 共同部分使用） */

/* 产品子导航：贴在顶栏下面 */
.chapternav{position:sticky;top:48px;z-index:95;background:#1d1d1f;border-bottom:1px solid rgba(255,255,255,.14);color:#f5f5f7}
.chapternav.light{background:var(--panel);border-bottom:1px solid var(--line);color:var(--text)}
.chapternav.light .chapternav-links a{color:var(--text)}
.chapternav-inner{max-width:1024px;margin:0 auto;padding:0 22px;height:52px;display:flex;align-items:center;justify-content:space-between}
.chapternav-title{font-size:19px;font-weight:600}
.chapternav-links{display:flex;gap:24px}
.chapternav-links a{font-size:12px;color:#f5f5f7;opacity:.8}
.chapternav-links a:hover{opacity:1}

/* hero：默认黑底，light 变体浅底 */
.ad-hero{background:#1d1d1f;color:#f5f5f7;text-align:center;padding:88px 22px 0;overflow:hidden}
.ad-hero h1{font-size:56px;font-weight:700;letter-spacing:-1px}
.ad-hero-sub{margin-top:10px;font-size:21px;opacity:.85}
.ad-hero .promo-links a{color:#2997ff}
.ad-hero.light{background:var(--panel);color:var(--text)}
.ad-hero.light .promo-links a{color:var(--blue)}

/* 特性区块 */
.feature{padding:96px 22px;text-align:center}
.feature h2{font-size:40px;font-weight:700;letter-spacing:-.5px}
.feature-sub{margin-top:10px;font-size:19px;opacity:.85}
.feature .fic{margin-top:44px;display:flex;justify-content:center;color:var(--text)}
.feature-dark{background:#1d1d1f;color:#f5f5f7}
.feature-dark .fic{color:#f5f5f7}
.feature-dark .promo-links a{color:#2997ff}

/* 特性图标：渐变大圆角砖，轻微悬浮动画 */
.fic .tile{width:168px;height:168px;border-radius:40px;display:flex;align-items:center;justify-content:center;color:#fff;box-shadow:0 20px 50px rgba(0,0,0,.22);animation:tileFloat 5s ease-in-out infinite}
.fic .tile svg{width:84px;height:84px}
.feature-dark .fic .tile{box-shadow:0 20px 50px rgba(0,0,0,.55)}
@keyframes tileFloat{0%,100%{transform:translateY(0)}50%{transform:translateY(-10px)}}
@media (prefers-reduced-motion: reduce){.fic .tile{animation:none}}

/* 步骤卡 */
.steps{max-width:980px;margin:44px auto 0;display:grid;grid-template-columns:repeat(3,1fr);gap:16px;text-align:left}
.step{border:1px solid var(--line);border-radius:18px;padding:28px 22px;background:var(--bg)}
.step .num{display:inline-flex;width:28px;height:28px;border-radius:50%;background:var(--blue);color:#fff;font-size:14px;font-weight:600;align-items:center;justify-content:center;margin-bottom:12px}
.step b{display:block;font-size:17px;margin-bottom:4px}
.step p{font-size:13.5px;color:var(--text-2)}

/* 订阅 CTA 区块 */
.feature-cta{padding:112px 22px}
.feature-cta .kicker{font-size:14px;font-weight:600;letter-spacing:.12em;text-transform:uppercase;color:#2997ff;margin-bottom:12px}
.feature-cta .perks{list-style:none;margin:28px auto 0;padding:0;max-width:420px;text-align:left}
.feature-cta .perks li{padding:12px 0 12px 30px;font-size:17px;position:relative;border-bottom:1px solid rgba(255,255,255,.12)}
.feature-cta .perks li:last-child{border-bottom:none}
.feature-cta .perks li::before{content:"";position:absolute;left:2px;top:50%;width:8px;height:14px;border:solid #2997ff;border-width:0 2px 2px 0;transform:translateY(-60%) rotate(45deg)}
.feature-cta .promo-links{margin-top:32px}
.btn{display:inline-block;background:#2997ff;color:#fff;padding:12px 26px;border-radius:980px;font-size:17px;font-weight:600}
.btn:hover{background:#0077ed;color:#fff}

/* 图文分栏（左右交替，照参考站排版） */
.split{max-width:1024px;margin:0 auto;padding:84px 22px;display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center}
.split .art-box{display:flex;justify-content:center}
.split .art-box .tile{width:200px;height:200px;border-radius:48px;display:flex;align-items:center;justify-content:center;color:#fff;box-shadow:0 24px 60px rgba(0,0,0,.2);animation:tileFloat 6s ease-in-out infinite}
.split .art-box .tile svg{width:100px;height:100px}
.split h3{font-size:36px;font-weight:700;letter-spacing:-.5px}
.split p{margin-top:12px;font-size:19px;line-height:1.5;color:var(--text-2)}
.split .more{margin-top:16px;display:inline-block;font-size:17px;color:var(--blue)}
.split.flip .art-box{order:2}
.split-dark{background:#1d1d1f;color:#f5f5f7}
.split-dark p{color:rgba(245,245,247,.7)}
.split-dark .more{color:#2997ff}

/* 大字段落 */
.bigline{padding:110px 22px;text-align:center}
.bigline p{max-width:820px;margin:0 auto;font-size:34px;font-weight:700;line-height:1.3;letter-spacing:-.5px}
.bigline.dark{background:#1d1d1f;color:#f5f5f7}

/* App 页：手机框 + logo */
.appphone{width:180px;height:360px;border:2px solid rgba(255,255,255,.25);border-radius:36px;background:#0a0a0a;display:flex;align-items:center;justify-content:center;margin:44px auto 56px}
.appphone img{width:72px;height:72px;border-radius:18px}

@media(max-width:760px){
  .chapternav-title{font-size:17px}
  .ad-hero h1{font-size:36px}
  .ad-hero-sub{font-size:17px}
  .feature{padding:64px 18px}
  .feature h2{font-size:28px}
  .feature-sub{font-size:16px}
  .steps{grid-template-columns:1fr}
  .split{grid-template-columns:1fr;gap:28px;padding:56px 18px}
  .split.flip .art-box{order:0}
  .split h3{font-size:26px}
  .split p{font-size:16px}
  .split .art-box .tile{width:150px;height:150px;border-radius:36px}
  .bigline{padding:70px 18px}
  .bigline p{font-size:24px}
}