/* ============================================================
   公共样式 (common.css) - 全站通用
   包含：重置、基础排版、导航栏、页脚、按钮、返回顶部、移动端菜单
   ============================================================ */
*,::after,::before{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;background:#0b1120;color:#f8fafc;line-height:1.7;overflow-x:hidden}img{display:block;max-width:100%;height:auto}a{color:inherit;text-decoration:none}::selection{background:#2563eb;color:#fff}.container{width:80%;margin:0 auto;padding:0 24px}@media (max-width:768px){.container{width:100%;padding:0 20px}}.section-padding{padding:60px 0}@media (min-width:768px){.section-padding{padding:80px 0}}.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;padding:14px 32px;font-weight:600;font-size:.95rem;border:none;border-radius:9999px;cursor:pointer;transition:all .5s cubic-bezier(.22,1,.36,1);position:relative;overflow:hidden}.btn-primary{background:#2563eb;color:#fff}.btn-primary:hover{background:#1d4ed8;transform:translateY(-2px);box-shadow:0 8px 32px rgba(37,99,235,.3)}.btn-outline{background:0 0;color:#f8fafc;border:1.5px solid rgba(37,99,235,.25)}.btn-outline:hover{border-color:#2563eb;color:#60a5fa;transform:translateY(-2px)}.btn-lg{padding:18px 44px;font-size:1.05rem}.btn-sm{padding:10px 22px;font-size:.85rem}.section-label{display:inline-block;font-size:.75rem;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:#60a5fa;margin-bottom:8px;border:1px solid rgba(37,99,235,.25);padding:4px 16px;border-radius:9999px}.section-title{font-size:clamp(1.8rem,3.5vw,2.8rem);font-weight:800;line-height:1.2;color:#f8fafc}.section-title .highlight{color:#60a5fa}.section-desc{font-size:clamp(1rem,1.1vw,1.15rem);color:#94a3b8;max-width:560px;margin-top:12px;line-height:1.7}.text-center{text-align:center}.text-center .section-desc{margin-left:auto;margin-right:auto}

/* 导航栏 */
#navbar{position:fixed;top:0;left:0;width:100%;padding:10px 24px;background:0 0;transition:background .5s,box-shadow .5s;z-index:50}@media (min-width:768px){#navbar{padding:14px 48px}}.navbar-inner{display:flex;align-items:center;justify-content:space-between;padding:0 5rem;margin:0 auto;width:100%}.nav-left{display:flex;align-items:center;flex-shrink:0}.nav-logo{width: 100%;flex-shrink:0;height:26px}@media (min-width:768px){.nav-logo{height:32px}}.nav-center{display:none;align-items:center;gap:24px}@media (min-width:768px){.nav-center{display:flex}}.nav-center a{font-size:.9rem;font-weight:500;color:#94a3b8;transition:color .2s;position:relative}.nav-center a::after{content:'';position:absolute;bottom:-4px;left:0;width:0;height:2px;background:#2563eb;transition:width .3s}.nav-center a:hover{color:#f8fafc}.nav-center a:hover::after{width:100%}.nav-right{display:flex;align-items:center;flex-shrink:0;gap:12px}.nav-right .btn{display:none}@media (min-width:768px){.nav-right .btn{display:inline-flex}}.hamburger{background:0 0;border:none;color:#f8fafc;font-size:22px;padding:4px 8px;cursor:pointer}@media (min-width:768px){.hamburger{display:none}}.mobile-menu{display:none;width:100%;background:rgba(11,17,32,.96);backdrop-filter:blur(16px);border-top:1px solid rgba(37,99,235,.25);padding:12px 24px 20px}.mobile-menu.open{display:block}.mobile-menu ul{display:flex;flex-direction:column;list-style:none;gap:0}.mobile-menu li{padding:10px 0;border-bottom:1px solid rgba(37,99,235,.1)}.mobile-menu li:last-child{border-bottom:none}.mobile-menu a{display:block;font-size:1rem;color:#f8fafc}.mobile-menu a:hover{color:#60a5fa}.scrolled{background:rgba(11,17,32,.92);backdrop-filter:blur(16px);box-shadow:0 4px 30px rgba(0,0,0,.6)}@media (max-width:768px){#navbar{background-color:rgba(11,17,32,.8);padding:0}#navbar .navbar-inner{padding:.75rem 1.25rem}}

/* 返回顶部 */
#backTop{position:fixed;bottom:24px;right:24px;z-index:99;width:44px;height:44px;border-radius:50%;border:none;background:#2563eb;color:#fff;font-size:1.1rem;cursor:pointer;opacity:0;visibility:hidden;transform:translateY(20px);transition:all .3s;box-shadow:0 4px 20px rgba(37,99,235,.3)}#backTop.show{opacity:1;visibility:visible;transform:translateY(0)}#backTop:hover{background:#1d4ed8;transform:translateY(-4px) scale(1.05)}

/* 移动端 CTA（公共结构，私有逻辑在 page-home.js） */
.mobile-cta{position:sticky;bottom:-100px;left:0;right:0;z-index:100;display:none;align-items:center;justify-content:space-between;gap:12px;padding:10px 16px;background:rgba(11,17,32,.96);backdrop-filter:blur(12px);border-top:1px solid rgba(37,99,235,.25);transition:bottom .3s}@media (max-width:767px){.mobile-cta{display:flex}}.mobile-cta.visible{bottom:0}.mobile-cta-text .title{font-size:.9rem;font-weight:700;color:#f8fafc}.mobile-cta-text .sub{font-size:.75rem;color:#94a3b8}.mobile-cta .btn{flex-shrink:0;font-size:.8rem;padding:10px 18px;min-height:38px}

/* 页脚 */
.footer { padding:48px 24px 32px; background:#0f172a; border-top:1px solid rgba(37,99,235,.1); }
.footer-inner { display:grid; grid-template-columns:1fr 1fr; gap:32px; max-width:80%; margin:0 auto; }
@media (min-width:640px) { .footer-inner { grid-template-columns:2fr 1fr 1fr 1fr; } }
@media (max-width:768px) { .footer-inner { max-width:100%; padding:0 20px; } }
.footer h4 { font-size:.85rem; font-weight:600; color:#f8fafc; margin-bottom:12px; letter-spacing:.02em; }
.footer a, .footer p { display:block; font-size:.85rem; color:#94a3b8; line-height:2; transition:color .2s; }
.footer a:hover { color:#60a5fa; }
.footer .brand p { color:#cbd5e1; line-height:1.7; max-width:300px; }
.footer .brand .logo-text { font-size:1.2rem; font-weight:800; color:#f8fafc; margin-bottom:6px; display:block; }
.footer .brand .logo-text span { color:#60a5fa; }
.footer-divider { max-width:80%; margin:32px auto 20px; height:1px; background:rgba(37,99,235,.1); }
.footer-copy { text-align:center; font-size:.8rem; color:#94a3b8; opacity:.6; max-width:80%; margin:0 auto; }
@media (max-width:768px) { .footer-copy, .footer-divider { max-width:100%; } }