:root {
    /* 核心曜石黑主题色 */
    --bg-base: #09090B;        
    --bg-darker: #040405;
    --bg-surface: #131418;     
    
    --text-primary: #FAFAFA;
    --text-muted: #A1A1AA;
    --border-color: #27272A;
    
    --amber: #FF7A00;
    --amber-hover: #E66A00;
    
    --radius-lg: 16px;
    --radius-md: 10px;
    --radius-sm: 6px;
    --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", sans-serif;
    background-color: var(--bg-base);
    color: var(--text-primary);
    line-height: 1.6;
    scroll-behavior: smooth;
    /* 极客网格背景 */
    background-image: 
        linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
    background-size: 30px 30px;
}

a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.max-w-1000 { max-width: 1000px; margin: 0 auto; }
.max-w-800 { max-width: 800px; margin: 0 auto; }
.text-center { text-align: center; }
.text-amber { color: var(--amber); }

.border-t { border-top: 1px solid var(--border-color); }
.bg-darker { background-color: var(--bg-darker); }
.section { padding: 100px 0; }

/* ================= 悬浮导航栏 ================= */
.floating-nav {
    position: fixed; top: 20px; left: 50%; transform: translateX(-50%);
    background: rgba(19, 20, 24, 0.6); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.08); border-radius: 100px;
    padding: 12px 24px; display: flex; align-items: center; justify-content: space-between;
    width: 92%; max-width: 900px; z-index: 100; transition: var(--transition);
}
.floating-nav.scrolled {
    background: rgba(9, 9, 11, 0.85);
    border-color: rgba(255, 122, 0, 0.3);
    box-shadow: 0 20px 40px rgba(0,0,0,0.5);
}
.nav-brand { font-weight: 700; font-size: 1.1rem; display: flex; align-items: center; gap: 8px; }
.logo-dot { width: 8px; height: 8px; background: var(--amber); border-radius: 50%; box-shadow: 0 0 10px var(--amber); }
.nav-links { display: flex; gap: 24px; }
.nav-links a { color: var(--text-muted); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--text-primary); }
.nav-btn { background: var(--text-primary); color: var(--bg-base); padding: 8px 18px; border-radius: 100px; font-weight: 700; font-size: 0.9rem; }
.nav-btn:hover { transform: scale(1.05); }

/* ================= 按钮系统 ================= */
.btn {
    display: inline-flex; justify-content: center; align-items: center;
    padding: 10px 24px; border-radius: 100px; font-weight: 600; cursor: pointer; border: 1px solid transparent;
}
.btn-large { padding: 14px 32px; font-size: 1.05rem; }
.btn-amber { background: var(--amber); color: #000; box-shadow: 0 4px 15px rgba(255,122,0,0.2); }
.btn-amber:hover { background: var(--amber-hover); transform: translateY(-2px); box-shadow: 0 8px 25px rgba(255,122,0,0.4); }
.btn-outline { border-color: var(--border-color); color: var(--text-primary); }
.btn-outline:hover { background: var(--text-primary); color: #000; }

/* ================= 英雄首屏 ================= */
.hero-section { padding: 180px 0 100px; position: relative; overflow: hidden; }
.hero-glow { position: absolute; top: -100px; left: 50%; transform: translateX(-50%); width: 700px; height: 700px; background: radial-gradient(circle, rgba(255,122,0,0.15) 0%, rgba(0,0,0,0) 70%); border-radius: 50%; z-index: -1; }
.badge { display: inline-flex; background: rgba(255,122,0,0.1); border: 1px solid rgba(255,122,0,0.2); color: var(--amber); padding: 6px 16px; border-radius: 100px; font-size: 0.85rem; font-weight: 600; margin-bottom: 24px; letter-spacing: 1px; }
.hero-title { font-size: 4rem; font-weight: 900; line-height: 1.1; margin-bottom: 24px; letter-spacing: -1px; }
.hero-desc { font-size: 1.15rem; color: var(--text-muted); max-width: 650px; margin: 0 auto 40px; }
.hero-actions { display: flex; gap: 20px; justify-content: center; }


/* ================= 核心模块：VPS 卡片系统 (绝对对称) ================= */
.vps-wrapper { max-width: 1000px; margin: 0 auto; }
.vps-section-title { text-align: center; margin-bottom: 40px; }
.vps-section-title h2 { font-size: 2.2rem; font-weight: 800; margin-bottom: 12px; }
.vps-section-title p { color: var(--text-muted); font-size: 1.05rem; }

/* 强大的 Grid 系统确保三列绝对对齐 */
.vps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 60px; }

/* 强大的 Flex 容器确保卡片等高与底部吸附 */
.vps-card {
    background: var(--bg-surface);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column; /* Flex 列方向 */
    overflow: hidden;
    position: relative;
    transition: var(--transition);
}
.vps-card:hover { transform: translateY(-6px); box-shadow: 0 20px 40px rgba(0,0,0,0.6); }

/* --- 主题色 CSS 变量映射引擎 --- */
.vps-card.theme-base   { --card-theme: #A1A1AA; }
.vps-card.theme-pro    { --card-theme: #EF4444; }
.vps-card.theme-blue   { --card-theme: #3B82F6; }
.vps-card.theme-purple { --card-theme: #8B5CF6; }
.vps-card.theme-gray   { --card-theme: #71717A; }
.vps-card.theme-dark   { --card-theme: #F5C518; background: #000; border-color: #333; }

.vps-card:hover { border-color: var(--card-theme); }

/* 卡片顶部霓虹发光线 */
.vps-card-line {
    height: 4px; width: 100%;
    background: var(--card-theme);
    box-shadow: 0 0 12px var(--card-theme);
}

.vps-badge {
    position: absolute; top: 16px; right: -32px;
    background: var(--card-theme); color: #fff;
    font-size: 0.75rem; font-weight: bold; padding: 4px 32px;
    transform: rotate(45deg); box-shadow: 0 2px 10px rgba(0,0,0,0.5);
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
}

.vps-card-header { padding: 30px 24px 20px; text-align: center; border-bottom: 1px dashed var(--border-color); }
.vps-card-title { font-size: 1.15rem; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.vps-card-price { font-size: 2.2rem; font-weight: 800; color: var(--card-theme); margin-bottom: 5px; }
.vps-card-price span { font-size: 0.9rem; font-weight: normal; color: var(--text-muted); }
.vps-card-desc { font-size: 0.85rem; color: var(--text-muted); background: rgba(255,255,255,0.05); padding: 4px 12px; border-radius: 20px; display: inline-block; }

/* Flex-grow 完美撑开中间层 */
.vps-card-body { padding: 24px; flex-grow: 1; display: flex; flex-direction: column; }
.vps-card-list { display: flex; flex-direction: column; gap: 12px; }
.vps-card-list li { font-size: 0.9rem; color: #CCC; display: flex; align-items: center; border-bottom: 1px solid rgba(255,255,255,0.03); padding-bottom: 8px; }
.vps-card-list li:last-child { border-bottom: none; }
.li-highlight { font-weight: 700; color: var(--card-theme) !important; }

/* Margin-top Auto 强制按钮吸底对齐 */
.vps-card-footer { padding: 0 24px 24px; margin-top: auto; }
.vps-btn {
    display: block; width: 100%; text-align: center; padding: 12px 0;
    border-radius: var(--radius-sm); font-weight: 600; transition: var(--transition);
    /* 幽灵按钮风格映射主题色 */
    background: rgba(255,255,255,0.03);
    border: 1px solid var(--card-theme);
    color: var(--card-theme);
}
.vps-btn:hover { background: var(--card-theme); color: #000; box-shadow: 0 4px 15px rgba(0,0,0,0.3); }
.theme-dark .vps-btn:hover { color: #000; } /* 黑金按钮特殊处理 */

.vps-divider { height: 1px; background: var(--border-color); margin: 60px auto; width: 60%; }


/* ================= 核心模块：VPS 矩阵表格 (全对称) ================= */
.vps-table-container { max-width: 1000px; margin: 0 auto; display: flex; flex-direction: column; gap: 40px; }

.vps-table-box {
    background: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.4);
    transition: var(--transition);
}
.vps-table-box:hover { border-color: rgba(255,255,255,0.15); }
.vps-table-scroll { overflow-x: auto; }

/* Table 强制严格对齐布局 */
.vps-table {
    width: 100%; min-width: 700px;
    border-collapse: collapse;
    table-layout: fixed; /* 绝对对称的核心：让列宽按比例精准分配 */
    text-align: center;
}

/* 主题渐变表头映射 */
.vps-tb-blue th.main-title   { background: linear-gradient(90deg, rgba(59, 130, 246, 0.2), transparent); border-left: 4px solid #3B82F6; }
.vps-tb-red th.main-title    { background: linear-gradient(90deg, rgba(239, 68, 68, 0.2), transparent); border-left: 4px solid #EF4444; }
.vps-tb-orange th.main-title { background: linear-gradient(90deg, rgba(249, 115, 22, 0.2), transparent); border-left: 4px solid #F97316; }
.vps-tb-cyan th.main-title   { background: linear-gradient(90deg, rgba(6, 182, 212, 0.2), transparent); border-left: 4px solid #06B6D4; }
.vps-tb-purple th.main-title { background: linear-gradient(90deg, rgba(139, 92, 246, 0.2), transparent); border-left: 4px solid #8B5CF6; }
.vps-tb-gray th.main-title   { background: linear-gradient(90deg, rgba(113, 113, 122, 0.2), transparent); border-left: 4px solid #71717A; }
.vps-tb-dark th.main-title   { background: linear-gradient(90deg, rgba(245, 197, 24, 0.15), transparent); border-left: 4px solid #F5C518; color: #F5C518; }

.vps-table th { padding: 18px 16px; font-weight: 600; color: var(--text-primary); border-bottom: 1px solid var(--border-color); }
.vps-table .main-title { font-size: 1.1rem; font-weight: 700; text-align: left; letter-spacing: 1px; }
.vps-table .sub-title th { font-size: 0.9rem; color: var(--text-muted); background: rgba(0,0,0,0.3); border-bottom: none; }

.vps-table td { padding: 16px; border-bottom: 1px solid rgba(255,255,255,0.03); font-size: 0.95rem; color: #CCC; vertical-align: middle; transition: var(--transition); }
.vps-table tbody tr:hover td { background: rgba(255,255,255,0.02); }
.vps-table tbody tr:last-child td { border-bottom: none; }

.vps-table .strong { font-weight: 700; color: var(--text-primary); font-size: 1rem; }
.vps-table .highlight { color: var(--amber); font-weight: 700; background: rgba(255,122,0,0.1); border-radius: 4px; }
.vps-table .notice { background: rgba(245, 197, 24, 0.05); color: var(--gold); text-align: left; font-size: 0.85rem; padding: 16px 24px; border-top: 1px solid rgba(245, 197, 24, 0.1); }

/* 表格内发光按钮 */
.vps-table-btn {
    display: inline-block; padding: 6px 20px;
    background: transparent; color: var(--amber);
    border: 1px solid var(--amber); border-radius: 20px;
    font-weight: 600; font-size: 0.85rem; transition: var(--transition);
}
.vps-table-btn:hover { background: var(--amber); color: #000; box-shadow: 0 4px 10px rgba(255,122,0,0.3); }


/* ================= 极简时间轴教程 ================= */
.tutorial-timeline { display: flex; flex-direction: column; gap: 32px; position: relative; }
.tutorial-timeline::before { content: ''; position: absolute; left: 24px; top: 0; bottom: 0; width: 2px; background: var(--border-color); }
.timeline-step { display: flex; gap: 24px; position: relative; z-index: 1; }
.step-marker { width: 50px; height: 50px; background: var(--bg-base); border: 2px solid var(--amber); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 800; color: var(--amber); flex-shrink: 0; box-shadow: 0 0 15px rgba(255,122,0,0.2); }
.step-content { background: var(--bg-surface); border: 1px solid var(--border-color); border-radius: var(--radius-md); padding: 24px; flex-grow: 1; transition: var(--transition); }
.step-content:hover { border-color: rgba(255,255,255,0.15); }
.step-content h3 { font-size: 1.2rem; margin-bottom: 12px; }
.step-content p { font-size: 0.95rem; color: var(--text-muted); }
.step-content code { background: rgba(0,0,0,0.5); padding: 2px 6px; border-radius: 4px; color: var(--amber); font-family: monospace; }


/* ================= 质感 FAQ ================= */
.faq-accordion { display: flex; flex-direction: column; gap: 16px; }
.accordion-item { background: var(--bg-surface); border: 1px solid var(--border-color); border-radius: var(--radius-md); overflow: hidden; transition: var(--transition); }
.accordion-item:hover { border-color: rgba(255,255,255,0.15); }
.accordion-header { width: 100%; padding: 24px; display: flex; justify-content: space-between; align-items: center; background: transparent; border: none; color: var(--text-primary); font-size: 1.05rem; font-weight: 600; text-align: left; cursor: pointer; }
.chevron { width: 10px; height: 10px; border-right: 2px solid var(--text-muted); border-bottom: 2px solid var(--text-muted); transform: rotate(45deg); transition: transform 0.3s; }
.accordion-item.active .chevron { transform: rotate(-135deg); border-color: var(--amber); }
.accordion-content { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; }
.accordion-content p { padding: 0 24px 24px; color: var(--text-muted); font-size: 0.95rem; line-height: 1.6; border-top: 1px solid rgba(255,255,255,0.03); padding-top: 16px; margin-top: -8px; }


/* ================= 页脚 ================= */
.site-footer { padding: 60px 0; background: #050505; }


/* ================= 滚动视差动画 ================= */
.reveal { opacity: 0; transform: translateY(40px); transition: opacity 0.8s ease, transform 0.8s ease; }
.reveal.active { opacity: 1; transform: translateY(0); }
.delay-1 { transition-delay: 0.15s; }
.delay-2 { transition-delay: 0.3s; }
.delay-3 { transition-delay: 0.45s; }


/* ================= 响应式降级 ================= */
@media (max-width: 1024px) {
    .vps-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    .floating-nav { width: 92%; padding: 10px 20px; }
    .nav-links, .nav-btn { display: none; }
    .hero-title { font-size: 2.5rem; }
    .hero-actions { flex-direction: column; gap: 16px; padding: 0 20px; }
    .vps-grid { grid-template-columns: 1fr; }
    .tutorial-timeline::before { left: 24px; }
    .step-marker { width: 40px; height: 40px; font-size: 1rem; }
    .step-content { padding: 16px; }
}