*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:#fff;color:#1a1a1a;line-height:1.78;font-size:16px}
a{color:#c62828;text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto;display:block}

.site-header{background:#fff;border-bottom:1px solid #ffcdd2;position:sticky;top:0;z-index:300}
.header-inner{max-width:1120px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;justify-content:space-between;gap:16px;position:relative}
.brand{display:flex;align-items:center;gap:10px;color:#111;font-weight:600;font-size:.95rem}
.brand:hover{text-decoration:none}
.brand img{border-radius:8px}
.brand em{font-style:normal;color:#c62828;font-weight:700}
.site-nav ul{display:flex;flex-wrap:wrap;gap:6px 18px;list-style:none}
.site-nav a{color:#555;font-size:.9rem;padding:4px 0}
.site-nav a.active,.site-nav a:hover{color:#1565c0;font-weight:600;border-bottom:2px solid #1565c0;text-decoration:none}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px;flex-direction:column;gap:5px}
.nav-toggle span{display:block;width:22px;height:2px;background:#333;transition:.2s}
.nav-toggle.is-open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle.is-open span:nth-child(2){opacity:0}
.nav-toggle.is-open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

.ads-top-bar{background:#fafafa;border-bottom:1px solid #eee;padding:10px 0}
.applist-title{font-size:.78rem;color:#888;text-align:center;margin-bottom:6px}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:12px}
#ads .caption{font-size:.7rem;color:#666;margin-top:4px;text-align:center;max-width:70px;line-height:1.3}

.hero-arc{background:linear-gradient(160deg,#fce4ec 0%,#e3f2fd 45%,#fff 100%);padding:42px 20px 38px;border-bottom:1px solid #f8bbd0;position:relative;overflow:hidden}
.hero-arc::after{content:"";position:absolute;bottom:-40px;left:-10%;right:-10%;height:80px;background:#fff;border-radius:50% 50% 0 0/100% 100% 0 0}
.hero-inner{max-width:1120px;margin:0 auto;position:relative;z-index:1}
.hero-arc .tag{display:inline-block;background:linear-gradient(90deg,#c62828,#1565c0);color:#fff;font-size:.76rem;font-weight:600;padding:5px 14px;border-radius:999px;margin-bottom:14px;letter-spacing:.04em}
.hero-arc h1{font-size:1.75rem;line-height:1.35;margin-bottom:16px;color:#111;max-width:820px}
.hero-arc .lead{color:#333;margin-bottom:12px;font-size:1.02rem;max-width:820px;text-align:justify}
.hero-arc .lead:last-of-type{margin-bottom:0}

.arc-nav{position:sticky;top:57px;z-index:250;background:rgba(255,255,255,.96);backdrop-filter:blur(8px);border-bottom:1px solid #ffcdd2;padding:10px 20px}
.arc-nav-inner{max-width:1120px;margin:0 auto;display:flex;flex-wrap:wrap;gap:8px;justify-content:center}
.arc-nav a{font-size:.82rem;padding:6px 14px;border:1px solid #e0e0e0;border-radius:999px;color:#555;background:#fafafa;transition:.15s;white-space:nowrap}
.arc-nav a:hover,.arc-nav a.is-active{background:linear-gradient(90deg,#fce4ec,#e3f2fd);border-color:#ef9a9a;color:#b71c1c;text-decoration:none;font-weight:600}

.arc-stack{max-width:1120px;margin:0 auto;padding:36px 20px 52px}

.arc-panel{position:relative;margin-bottom:40px;padding:32px 30px 30px;border-radius:20px;border:1px solid #e8e8e8;background:#fff;box-shadow:0 4px 20px rgba(0,0,0,.05)}
.arc-panel::before{content:"";position:absolute;top:-8px;width:120px;height:120px;border:3px solid transparent;border-top-color:#c62828;border-right-color:#1565c0;border-radius:50%;opacity:.35;pointer-events:none}
.arc-panel:nth-child(odd){margin-left:0;margin-right:48px;transform:rotate(-.4deg)}
.arc-panel:nth-child(even){margin-left:48px;margin-right:0;transform:rotate(.35deg)}
.arc-panel:nth-child(odd)::before{right:24px}
.arc-panel:nth-child(even)::before{left:24px;transform:scaleX(-1)}

.arc-label{display:inline-block;font-size:.72rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:#1565c0;background:#e3f2fd;padding:4px 12px;border-radius:999px;margin-bottom:12px}
.arc-panel h2{font-size:1.2rem;color:#111;margin-bottom:14px;line-height:1.4;padding-right:80px}
.arc-panel p{margin-bottom:12px;color:#333;font-size:.97rem;text-align:justify}
.arc-panel p:last-child{margin-bottom:0}
.arc-panel figure{margin:16px 0;border:1px solid #eee;border-radius:12px;overflow:hidden}
.arc-panel figcaption{font-size:.8rem;color:#666;padding:8px 12px;background:#fafafa}

.rose-tip{margin:14px 0;padding:14px 18px;background:#fce4ec;border-left:4px solid #c62828;border-radius:0 10px 10px 0;font-size:.93rem;color:#880e4f}
.blue-tip{margin:14px 0;padding:14px 18px;background:#e3f2fd;border-left:4px solid #1565c0;border-radius:0 10px 10px 0;font-size:.93rem;color:#0d47a1}
.split-media{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:16px 0;align-items:start}
.split-media figure{border:1px solid #eee;border-radius:12px;overflow:hidden}

.faq-arc{margin-top:36px;padding:28px;background:linear-gradient(135deg,#fce4ec,#e3f2fd);border-radius:20px;border:1px solid #e0e0e0}
.faq-arc h2{font-size:1.2rem;margin-bottom:16px;color:#111}
.faq-arc details{border:1px solid #ddd;border-radius:10px;margin-bottom:8px;background:#fff}
.faq-arc summary{padding:12px 16px;cursor:pointer;font-weight:500;color:#222;list-style:none}
.faq-arc summary::-webkit-details-marker{display:none}
.faq-arc details[open] summary{border-bottom:1px solid #eee;background:#fafafa}
.faq-arc details p{padding:12px 16px;color:#444;font-size:.94rem}

.finish-arc{margin-top:32px;padding:26px 28px;background:linear-gradient(135deg,#fce4ec,#e3f2fd);border:1px solid #f8bbd0;border-radius:20px;transform:none!important;margin-left:0!important;margin-right:0!important}
.finish-arc h2{font-size:1.1rem;margin-bottom:12px;color:#111}
.finish-arc p{margin-bottom:10px;color:#333;font-size:.95rem}

.site-footer{background:#fafafa;border-top:1px solid #eee;padding:28px 20px;text-align:center;font-size:.88rem;color:#666}
.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:14px;margin-bottom:10px}
.footer-links a{color:#555}
.prose-page{max-width:760px;margin:40px auto;padding:0 20px 48px}
.prose-page h1{font-size:1.5rem;margin-bottom:16px}
.prose-page h2{font-size:1.1rem;margin:20px 0 10px;color:#333}
.prose-page p{margin-bottom:12px;color:#444;line-height:1.75}
.error-page{text-align:center;padding:80px 20px}
.error-page h1{font-size:3rem;color:#c62828;margin-bottom:12px}

@media(max-width:860px){
  .arc-panel:nth-child(odd),.arc-panel:nth-child(even){margin-left:0;margin-right:0;transform:none}
  .arc-panel h2{padding-right:0}
  .split-media{grid-template-columns:1fr}
}
@media(max-width:720px){
  .nav-toggle{display:flex}
  .site-nav{position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid #eee;padding:12px 20px;display:none;box-shadow:0 8px 20px rgba(0,0,0,.08)}
  .site-nav.is-open{display:block}
  .site-nav ul{flex-direction:column;gap:10px}
  .hero-arc h1{font-size:1.35rem}
  .arc-nav{top:53px}
}