@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500&family=Noto+Sans+SC:wght@400;500&family=Noto+Serif+SC:wght@600;700&display=swap');

:root {
    --bg: #1E1913;
    --panel: #292219;
    --ink: #EFE8D8;
    --dim: #9A8C72;
    --line: rgba(239, 232, 216, 0.09);
    --acc: #C03A2E;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    background-color: var(--bg);
    color: var(--ink);
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-weight: 400;
    line-height: 1.9;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Noto Serif SC', serif;
    font-weight: 600;
    color: var(--ink);
}

a { color: var(--ink); text-decoration: none; transition: color 0.3s; }
a:hover { color: var(--acc); }
ul { list-style: none; }
img { max-width: 100%; height: auto; }

/* Scroll Reveal */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.8s cubic-bezier(0.2, 0.8, 0.2, 1), transform 0.8s cubic-bezier(0.2, 0.8, 0.2, 1);
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Background Canvas & Badges */
#bg-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -2;
    pointer-events: none;
}
.bg-badge {
    position: fixed;
    z-index: -1;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--dim);
    pointer-events: none;
}
.bg-badge.tl { top: 20px; left: 20px; }
.bg-badge.br { bottom: 20px; right: 20px; }
.bg-badge.bl { bottom: 20px; left: 20px; }

/* Layout */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; position: relative; z-index: 1; }
section { padding: 80px 0;  scroll-margin-top: 80px; }


.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--acc);
    color: var(--ink);
    padding: 8px;
    z-index: 1000;
    transition: top 0.3s;
}
.skip-link:focus {
    top: 0;
}

/* Header & Nav */
header { background: rgba(30, 25, 19, 0.85); border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 100; backdrop-filter: blur(8px); }
.nav-container { display: flex; justify-content: center; align-items: center; height: 64px; position: relative; }
.logo { position: absolute; left: 20px; }
.logo a { font-family: 'Noto Serif SC', serif; font-size: 24px; font-weight: 700; color: var(--ink); letter-spacing: 0.05em; }
.nav-links { display: flex; gap: 24px; align-items: center; }
.header-btn { position: absolute; right: 20px; margin: 0 !important; top: 50%; transform: translateY(-50%); }
.nav-links a { font-family: 'IBM Plex Mono', monospace; font-size: 13px; text-transform: uppercase; color: var(--dim); }
.nav-links a:hover { color: var(--acc); }
.menu-toggle { display: none; }
.menu-icon { display: none; font-size: 24px; cursor: pointer; user-select: none; color: var(--ink); }

/* Buttons */
.btn {
    display: inline-block; padding: 12px 24px; border-radius: 4px; font-family: 'Noto Sans SC', sans-serif;
    font-weight: 500; text-decoration: none; transition: all 0.3s ease; margin: 8px; border: 1px solid var(--line);
}
.btn-primary { background: var(--acc); color: var(--ink) !important; border-color: var(--acc); }
.btn-primary:hover { background: transparent; border-color: rgba(192,58,46,0.5); color: var(--acc) !important; }
.btn-secondary, .btn-outline { background: transparent; color: var(--dim); border-color: var(--line); }
.btn-secondary:hover, .btn-outline:hover { border-color: rgba(192,58,46,0.5); color: var(--acc); }

/* Hero Section */
.hero { text-align: center; padding: 120px 20px; background: transparent; }
.hero h1 { font-size: 48px; margin-bottom: 24px; line-height: 1.2; font-weight: 700; }
.hero p { font-size: 22px; margin-bottom: 30px; color: var(--dim); }
.hero-desc { font-size: 16px; margin-bottom: 40px; max-width: 700px; margin-left: auto; margin-right: auto; color: var(--dim); }

/* Components */
.section-title { text-align: center; font-size: 36px; margin-bottom: 50px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }

.card, .pricing-card, .faq-item, .page-content {
    background: var(--panel);
    padding: 40px 30px;
    border-radius: 4px;
    border: 1px solid var(--line);
    transition: all 0.3s ease;
    box-shadow: none;
}
.img-card { padding: 0; overflow: hidden; display: flex; flex-direction: column; }
.card-image { width: 100%; height: auto; border-bottom: 1px solid var(--line); display: block; object-fit: cover; aspect-ratio: 16/9; }
.img-card .card-content { padding: 40px 30px; flex-grow: 1; }
.sm-card {
    display: flex; align-items: center; padding: 15px 20px; border: 1px solid var(--line);
    border-radius: 4px; background: var(--bg); transition: all 0.3s ease;
    font-size: 14px; line-height: 1.5; color: var(--ink) !important; text-decoration: none;
}
.sm-card:hover { border-color: rgba(192,58,46,0.5); color: var(--acc) !important; transform: translateY(-2px); }
.card:hover, .pricing-card:hover, .faq-item:hover { border-color: rgba(192,58,46,0.5); transform: none; }
.card:hover h3, .pricing-card:hover h3, .faq-item:hover h3 { color: var(--acc); }

.card h3 { margin-bottom: 20px; font-size: 22px; }
.card p, .faq-item p, .page-content p { color: var(--dim); }

/* Pricing Specific */
.pricing-section { background: transparent;  scroll-margin-top: 80px; }
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; align-items: stretch; }
.pricing-card { display: flex; flex-direction: column; text-align: center; }
.pricing-card.featured { border-color: rgba(192,58,46,0.5); position: relative; transform: none; }
.pricing-card.featured::before {
    content: "最受欢迎"; position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
    background: var(--acc); color: var(--ink); padding: 4px 16px; border-radius: 2px;
    font-family: 'IBM Plex Mono', monospace; font-size: 11px; font-weight: 500;
}
.price { font-family: 'IBM Plex Mono', monospace; font-size: 32px; font-weight: 500; color: var(--ink); margin: 25px 0; }
.price span { font-size: 16px; color: var(--dim); font-weight: 400; }
.features-list { text-align: left; margin-bottom: 30px; flex-grow: 1; }
.features-list li { margin-bottom: 12px; padding-left: 24px; position: relative; color: var(--dim); }
.features-list li::before { content: "✓"; position: absolute; left: 0; color: var(--acc); }
.pricing-card .btn { width: 100%; margin: 0; box-sizing: border-box; }

/* FAQ Specific */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { padding: 25px; margin-bottom: 20px; }
.faq-item h3 { font-size: 18px; margin-bottom: 12px; }

/* Page Content (Subpages) */
.page-content { margin-top: 40px; margin-bottom: 60px; }
.page-content h1 { font-size: 36px; border-bottom: 1px solid var(--line); padding-bottom: 15px; margin-bottom: 30px; }
.page-content h2 { font-size: 24px; margin-top: 40px; margin-bottom: 20px; }
.page-content ul { list-style: disc; margin-left: 25px; margin-bottom: 20px; color: var(--dim); }

/* Footer */
footer { border-top: 1px solid var(--line); padding: 50px 0 30px; text-align: center; background: transparent; }
.footer-links { display: flex; justify-content: center; gap: 40px; margin-bottom: 30px; }
.footer-links a { font-family: 'IBM Plex Mono', monospace; font-size: 13px; text-transform: uppercase; color: var(--dim); }

/* Responsive */
@media (max-width: 992px) {
    .grid-3, .pricing-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    section { padding: 50px 0;  scroll-margin-top: 80px; }
    .nav-container { justify-content: space-between; }
    .logo { position: static; }
    .header-btn { position: static; transform: none; width: 100%; margin: 10px 0 !important; }
    .menu-icon { display: block; }
    .nav-links { display: none; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: var(--bg); padding: 20px; border-bottom: 1px solid var(--line); gap: 15px; align-items: flex-start !important; }
    .menu-toggle:checked ~ .nav-links { display: flex; }
    .hero { padding: 80px 20px; }
    .hero h1 { font-size: 36px; }
    .grid-3, .grid-2, .pricing-grid { grid-template-columns: 1fr; }
    .pricing-card.featured { margin-top: 20px; margin-bottom: 20px; }
    .btn { display: block; margin: 10px 0; width: 100%; }
    .footer-links { flex-direction: column; gap: 20px; }
    .page-content { padding: 30px 20px; }
}

details.faq-item { cursor: pointer; }
details.faq-item summary { font-family: 'Noto Serif SC', serif; font-size: 18px; margin-bottom: 0; color: var(--ink); list-style: none; outline: none; }
details.faq-item summary::-webkit-details-marker { display: none; }
details.faq-item summary:focus { color: var(--acc); }
details.faq-item[open] summary { margin-bottom: 10px; color: var(--acc); }