:root {
    --primary-hue: 220; /* 更深的蓝色 */
    --secondary-hue: 175; /* 青色 */
    --accent-hue: 285; /* 紫色 */

    --primary: hsl(var(--primary-hue), 80%, 55%);
    --primary-light: hsl(var(--primary-hue), 80%, 65%);
    --primary-dark: hsl(var(--primary-hue), 80%, 40%);

    --secondary: hsl(var(--secondary-hue), 70%, 50%);
    --secondary-light: hsl(var(--secondary-hue), 70%, 60%);

    --accent: hsl(var(--accent-hue), 75%, 60%);
    --accent-light: hsl(var(--accent-hue), 75%, 70%);
    --accent-dark: hsl(var(--accent-hue), 75%, 50%);

    --dark-bg1: #0A0E17; /* 更深的背景 */
    --dark-bg2: #141A25; /* 更深的面板 */
    --dark-bg3: #1E2633; /* 更深的悬停状态 */

    --light-text1: #F0F5FF; /* 更亮的白色文本 */
    --light-text2: #B8C4DF; /* 略带蓝色的二级文本 */
    --light-text3: #7D85A0; /* 三级文本 */

    --gradient-bg: linear-gradient(135deg, rgba(var(--primary-hue), 80%, 20%, 0.8), rgba(var(--accent-hue), 75%, 25%, 0.8));
    --card-gradient: linear-gradient(135deg, rgba(20, 26, 37, 0.8), rgba(30, 38, 51, 0.8));
    
    --border-color: hsla(var(--primary-hue), 40%, 40%, 0.7);
    --border-glow: hsla(var(--primary-hue), 80%, 60%, 0.5);
    --neon-glow-primary: 0 0 10px var(--primary), 0 0 20px hsla(var(--primary-hue),80%,55%,0.4);
    --neon-glow-accent: 0 0 10px var(--accent), 0 0 20px hsla(var(--accent-hue),75%,60%,0.4);

    --font-sans: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Roboto Mono', monospace;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --header-height: 70px;

    --card-shadow: 0 15px 35px rgba(0,0,0,0.25);
    --transition-swift: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- 基础与重置 --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    font-family: var(--font-sans);
    line-height: 1.7;
    color: var(--light-text2);
    background-color: var(--dark-bg1);
    background-image: radial-gradient(circle at 80% 20%, hsla(var(--primary-hue), 80%, 40%, 0.15), transparent 40%),
                     radial-gradient(circle at 20% 80%, hsla(var(--accent-hue), 75%, 40%, 0.15), transparent 40%);
    background-attachment: fixed;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    position: relative;
}
body.no-scroll { overflow: hidden; }

/* --- 背景元素 --- */
.bg-grid {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background-image:
        linear-gradient(hsla(var(--primary-hue), 30%, 25%, 0.5) 1px, transparent 1px),
        linear-gradient(90deg, hsla(var(--primary-hue), 30%, 25%, 0.5) 1px, transparent 1px);
    background-size: 50px 50px;
    z-index: -2; opacity: 0.15;
}
.particles, #particles-js-custom {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    z-index: -1; overflow: hidden; opacity: 0.5;
}
.digital-rain {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    z-index: -1; opacity: 0.08; pointer-events: none;
}
.digital-rain canvas { position: absolute; top: 0; left: 0; }

/* --- 通用布局与排版 --- */
.container { width: 100%; max-width: 1300px; margin: 0 auto; padding: 0 1.5rem; }
a { color: var(--primary-light); text-decoration: none; transition: var(--transition-swift); }
a:hover { color: var(--secondary-light); }

h1, h2, h3, h4 { font-weight: 700; line-height: 1.3; color: var(--light-text1); }
p { font-size: 1.05rem; }
.section-title {
    font-size: clamp(2.25rem, 5vw, 3rem);
    margin-bottom: 2rem; text-align: center; position: relative;
    color: var(--light-text1);
    padding-bottom: 1rem;
    background: linear-gradient(90deg, var(--primary-light), var(--accent-light));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: inline-block;
    width: 100%;
}
.section-title::after {
    content: ''; position: absolute; bottom: 0; left: 50%; transform: translateX(-50%);
    width: 100px; height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    border-radius: 2px;
    box-shadow: var(--neon-glow-primary);
}
section .section-subtitle {
    font-size: clamp(1.1rem, 2.5vw, 1.25rem);
    max-width: 800px; margin: 0 auto 4rem;
    text-align: center; color: var(--light-text2);
}

/* --- 导航栏 --- */
.navbar {
    display: flex; justify-content: space-between; align-items: center;
    padding: 1rem 2.5rem;
    position: fixed; top: 0; left: 0; width: 100%;
    background: hsla(var(--primary-hue), 15%, 5%, 0.85);
    backdrop-filter: blur(15px); -webkit-backdrop-filter: blur(15px);
    z-index: 1000; border-bottom: 1px solid var(--border-color);
    transition: padding var(--transition-swift), background-color var(--transition-swift);
}
.navbar.scrolled {
    padding: 0.75rem 2.5rem;
    background: hsla(var(--primary-hue), 15%, 5%, 0.95);
    box-shadow: 0 5px 25px rgba(0,0,0,0.3);
}
.logo {
    font-size: 1.8rem; font-weight: 700;
    color: var(--light-text1);
    display: flex; align-items: center; gap: 0.6rem;
    text-decoration: none;
}
.logo-icon-main {
    width: 2.2rem; height: 2.2rem;
    stroke: var(--primary);
    filter: drop-shadow(0 0 8px hsla(var(--primary-hue),80%,60%,0.7));
    transition: stroke var(--transition-swift), filter var(--transition-swift);
}
.logo:hover .logo-icon-main { 
    stroke: var(--secondary-light); 
    filter: drop-shadow(0 0 12px hsla(var(--secondary-hue),70%,60%,0.8));
}
.logo:hover { color: var(--light-text1); }

.nav-links-container { display: flex; align-items: center; gap: 2rem; }
.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a {
    color: var(--light-text2); text-decoration: none; font-weight: 500;
    transition: color var(--transition-swift); position: relative; padding: 0.5rem 0;
    font-size: 1.05rem;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: -4px; left: 0;
    width: 0; height: 2px; background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width var(--transition-swift);
    box-shadow: var(--neon-glow-primary);
}
.nav-links a:hover, .nav-links a.active { color: var(--light-text1); }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

.github-btn {
    display: inline-flex; align-items: center; gap: 0.5rem; padding: 0.8rem 1.4rem;
    background: linear-gradient(45deg, var(--primary-dark), var(--accent-dark));
    color: white; border: none; border-radius: var(--radius-md);
    font-weight: 600; cursor: pointer; text-decoration: none;
    transition: transform var(--transition-swift), box-shadow var(--transition-swift), background var(--transition-swift);
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}
.github-btn:hover {
    background: linear-gradient(45deg, var(--primary), var(--accent));
    transform: translateY(-3px) scale(1.03);
    box-shadow: 0 10px 25px hsla(var(--accent-hue), 75%, 50%, 0.3);
}
.github-btn i { margin-right: 0.4em; }
.menu-btn { display: none; font-size: 1.5rem; cursor: pointer; color: var(--light-text1); background: none; border: none; z-index: 1001;}
.menu-btn i { transition: transform var(--transition-swift); }

/* --- 英雄区块 --- */
.hero {
    min-height: 100vh; display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    padding: calc(var(--header-height) + 3rem) 1.5rem 6rem;
    text-align: center; position: relative; overflow: hidden;
}
.hero-bg-shapes {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%; overflow: hidden; z-index: 0;
}
.hero-abstract-svg {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%,-50%); width:150%; height:150%; opacity:0.08; animation: rotateSvg 70s linear infinite;
}
.hero-shape { animation: floatShape 15s ease-in-out infinite alternate; }
@keyframes rotateSvg { from {transform: translate(-50%,-50%) rotate(0deg);} to {transform: translate(-50%,-50%) rotate(360deg);}}
@keyframes floatShape { 0% {transform: translateY(0px) scale(1) rotate(0deg);} 50% {transform: translateY(-30px) scale(1.05) rotate(10deg);} 100% {transform: translateY(0px) scale(1) rotate(0deg);}}

.hero-content { position: relative; z-index: 1; max-width: 1000px; }
.hero-intro { margin-bottom: 3rem; }
.badge {
    display: inline-block; background: hsla(var(--primary-hue), 80%, 55%, 0.15);
    color: var(--primary-light); padding: 0.6rem 1.5rem; border-radius: 50px;
    font-size: 1rem; font-weight: 600; margin-bottom: 2rem;
    border: 1px solid hsla(var(--primary-hue), 80%, 55%, 0.3);
    box-shadow: 0 0 20px hsla(var(--primary-hue), 80%, 55%, 0.2);
}
.badge i { margin-right: 0.5em; }

.hero h1 {
    font-size: clamp(2.5rem, 5.5vw, 4rem); line-height: 1.2; margin-bottom: 2rem;
    font-weight: 800; color: var(--light-text1);
}
.hero-title-static {
    display: block;
    margin-bottom: 0.2em;
    color: var(--light-text2);
    font-weight: 700;
}
.typed-text-container-hero {
    background: linear-gradient(90deg, var(--primary-light), var(--accent-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
    font-weight: 800;
}
.typed-cursor {
    opacity: 1;
    animation: typedjsBlink 0.7s infinite;
    color: var(--accent);
    font-weight: bold;
}
@keyframes typedjsBlink { 50% { opacity: 0.0; } }

.hero .subtitle {
    font-size: clamp(1.15rem, 2.5vw, 1.35rem); max-width: 800px;
    margin: 0 auto 3rem; color: var(--light-text2);
}
.cta-buttons { display: flex; gap: 1.5rem; justify-content: center; flex-wrap: wrap; }
.primary-btn, .secondary-btn {
    padding: 1rem 2.5rem; font-size: 1.1rem; font-weight: 600;
    border-radius: var(--radius-md); cursor: pointer;
    transition: var(--transition-swift);
    display: inline-flex; align-items: center; gap: 0.6rem; text-decoration: none;
    position: relative; overflow: hidden; z-index: 1;
}
.primary-btn {
    background: linear-gradient(45deg, var(--primary), var(--secondary)); color: white;
    border: none; box-shadow: 0 8px 25px hsla(var(--secondary-hue), 70%, 50%, 0.3);
}
.primary-btn:hover { 
    transform: translateY(-4px) scale(1.03); 
    box-shadow: 0 15px 35px hsla(var(--secondary-hue), 70%, 50%, 0.4);
}
.primary-btn::before {
    content: ''; position: absolute; top: 0; left: -100%; width: 100%; height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.6s; z-index: 0;
}
.primary-btn:hover::before { left: 100%; }

.secondary-btn {
    background: transparent; color: var(--primary-light);
    border: 2px solid var(--primary);
    box-shadow: 0 5px 15px rgba(0,0,0,0.15);
}
.secondary-btn:hover { 
    background: hsla(var(--primary-hue), 80%, 55%, 0.15); 
    color: var(--light-text1); 
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.2), 0 0 15px hsla(var(--primary-hue), 80%, 55%, 0.2);
}

.hero-stats {
    display: flex; justify-content: center; gap: clamp(2rem, 6vw, 4.5rem); margin-top: 5rem; flex-wrap: wrap;
    background: hsla(var(--primary-hue), 20%, 10%, 0.4);
    padding: 2.5rem; border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--card-shadow);
    backdrop-filter: blur(10px);
}
.stat-item { text-align: center; position: relative; }
.stat-value {
    font-size: clamp(2.5rem, 5vw, 3.25rem); font-weight: 700;
    background: linear-gradient(90deg, var(--primary-light), var(--accent-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
    margin-bottom: 0.5rem;
    font-family: var(--font-mono);
}
.stat-value::after {
    content: attr(data-suffix); font-size: 0.6em; vertical-align: super; margin-left: 0.2em;
    color: var(--secondary-light); opacity: 0.9;
}
.stat-label { color: var(--light-text2); font-weight: 500; font-size: 1rem; }


/* --- 共享卡片样式 --- */
.feature-card, .workflow-item .workflow-content, .tech-item, .community-card {
    background: hsla(var(--primary-hue), 15%, 10%, 0.7);
    border-radius: var(--radius-lg);
    padding: 2.5rem; transition: var(--transition-smooth);
    border: 1px solid var(--border-color);
    position: relative; overflow: hidden;
    box-shadow: var(--card-shadow);
    z-index: 1;
    display: flex; /* 为更好的内部对齐 */
    flex-direction: column; /* 堆叠图标、标题、文本 */
    backdrop-filter: blur(10px);
}
.feature-card::before, .workflow-item .workflow-content::before, .tech-item::before, .community-card::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0;
    border-radius: inherit;
    background: radial-gradient(ellipse at center, hsla(var(--primary-hue), 80%, 60%, 0.15) 0%, transparent 70%);
    opacity: 0; transition: opacity var(--transition-smooth); z-index: -1;
}
.feature-card:hover, .workflow-item:hover .workflow-content, .tech-item:hover, .community-card:hover {
    transform: translateY(-10px);
    border-color: var(--border-glow);
    background: hsla(var(--primary-hue), 20%, 15%, 0.8);
    box-shadow: 0 15px 40px rgba(0,0,0,0.3), var(--neon-glow-primary);
}
.feature-card:hover::before, .workflow-item:hover .workflow-content::before, .tech-item:hover::before, .community-card:hover::before {
    opacity: 1;
}
.feature-card .feature-icon, .community-card .community-icon {
    font-size: 2.5rem; color: var(--primary); margin-bottom: 1.5rem;
    display: inline-block;
    filter: drop-shadow(var(--neon-glow-primary));
}
.feature-card h3, .community-card h3 { 
    font-size: 1.5rem; margin-bottom: 1rem; 
    color: var(--light-text1);
    background: linear-gradient(90deg, var(--light-text1), var(--primary-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.feature-card p, .community-card p { color: var(--light-text2); font-size: 1.05rem; flex-grow: 1; line-height: 1.8; }
.community-card .community-btn { margin-top: auto; /* 推动按钮到底部 */ }


/* --- 功能区块 --- */
.features-section { padding: 6rem 1.5rem; background: var(--dark-bg1); }
.features-grid {
    display: grid;
    gap: 2.5rem;
    /* 小屏幕默认1列 */
    grid-template-columns: 1fr;
}
/* 中等屏幕: 2列 */
@media (min-width: 640px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
/* 大屏幕: 3列 */
@media (min-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}
/* 确保卡片有最大宽度 */
.feature-card {
    max-width: 450px; /* 根据需要调整 */
    margin-left: auto; /* 如果网格容器本身已居中或已填充，则有助于居中 */
    margin-right: auto;
}
/* 当网格不填满宽度时, 使网格本身居中 */
.features-grid {
    justify-content: center; /* 如果网格轨道中有额外空间，这会起作用 */
}


/* --- 工作原理/ReAct工作流部分 --- */
.how-it-works-section { 
    padding: 6rem 1.5rem; 
    background: linear-gradient(to bottom, var(--dark-bg1), var(--dark-bg2));
    position: relative;
    overflow: hidden;
}
.how-it-works-section::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(
        ellipse at center,
        hsla(var(--primary-hue), 70%, 40%, 0.15) 0%,
        transparent 70%
    );
    z-index: 0;
}
.how-it-works-section > * {
    position: relative;
    z-index: 1;
}
.workflow-timeline { position: relative; max-width: 1000px; margin: 3rem auto 0; }
.workflow-timeline::before {
    content: ''; position: absolute; top: 0; bottom: 0; left: 50%;
    width: 4px; background: linear-gradient(to bottom, var(--primary) 0%, var(--secondary) 100%);
    transform: translateX(-50%); border-radius: 5px;
    box-shadow: var(--neon-glow-primary);
}
.react-workflow .workflow-item .workflow-content { padding-top: 2.5rem; }
.react-workflow .workflow-step-num {
    position: absolute; top: 1.2rem; left: 1.8rem;
    background: var(--accent-dark); color: var(--light-text1);
    padding: 0.3rem 0.8rem; border-radius: var(--radius-sm);
    font-size: 0.85rem; font-weight: 700; font-family: var(--font-mono);
    letter-spacing: 0.05em;
    box-shadow: 0 3px 10px rgba(0,0,0,0.3);
}
.workflow-item { display: flex; margin-bottom: 4rem; position: relative; width: 50%; }
.workflow-item:nth-child(odd) { left: 0; padding-right: 50px; justify-content: flex-end; text-align: right; }
.workflow-item:nth-child(even) { left: 50%; padding-left: 50px; justify-content: flex-start; text-align: left;}
.workflow-item:nth-child(odd) .workflow-icon { right: -35px; transform: translateX(50%); }
.workflow-item:nth-child(even) .workflow-icon { left: -35px; transform: translateX(-50%); }
.workflow-icon {
    position: absolute; top: 50%; transform: translateY(-50%);
    width: 70px; height: 70px; background: var(--dark-bg1);
    border: 3px solid var(--secondary); border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.8rem; color: var(--secondary); z-index: 2;
    box-shadow: 0 0 25px hsla(var(--secondary-hue), 70%, 50%, 0.5);
}
.workflow-content { width: calc(100% - 20px); }
.workflow-item h3 { 
    font-size: 1.5rem; margin-bottom: 0.75rem; 
    background: linear-gradient(90deg, var(--light-text1), var(--secondary-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.workflow-item p { font-size: 1.05rem; color: var(--light-text2); line-height: 1.8; }

/* --- 技术栈部分 --- */
.tech-stack-section { 
    padding: 6rem 1.5rem; 
    background: linear-gradient(to bottom, var(--dark-bg2), var(--dark-bg1));
}
.tech-grid-condensed {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2.5rem;
    margin-top: 3rem;
}
.tech-grid-condensed .tech-item {
    flex-grow: 0; /* 不增长 */
    flex-shrink: 0; /* 不收缩 */
    flex-basis: 280px; /* 每项的理想宽度 */
    max-width: calc(100% - 1rem); /* 确保适合小屏幕 */
}
/* 在非常小的屏幕上，让它们堆叠 */
@media (max-width: 560px) {
    .tech-grid-condensed .tech-item {
        flex-basis: 100%;
    }
}
/* 对于每行2个项目，如果空间允许2个项目+间隔 */
@media (min-width: 560px) and (max-width: 830px) {
    .tech-grid-condensed {
        max-width: 600px; /* 2*280 + 2*20 (间隙) */
        margin-left:auto;
        margin-right:auto;
    }
}
/* 对于每行3个项目，如果空间允许3个项目+间隔 */
@media (min-width: 830px) and (max-width: 1100px) {
     .tech-grid-condensed {
        max-width: 900px; /* 3*280 + 2*30 (间隙) */
        margin-left:auto;
        margin-right:auto;
    }
}
/* 每行最多5个项目 */
@media (min-width: 1370px) {
     .tech-grid-condensed {
        max-width: 1500px; /* 5*280 + 4*20 (间隙) */
    }
}


.tech-item { padding: 2.25rem; text-align: center; }
.tech-icon { 
    font-size: 3.5rem; 
    color: var(--primary-light); 
    margin-bottom: 1.25rem; 
    transition: transform var(--transition-swift), color var(--transition-swift);
    filter: drop-shadow(var(--neon-glow-primary));
}
.tech-item:hover .tech-icon { 
    transform: scale(1.2) rotate(5deg); 
    color: var(--secondary-light);
    filter: drop-shadow(var(--neon-glow-accent));
}
.tech-item h3 { 
    font-size: 1.25rem; 
    color: var(--light-text1); 
    font-weight: 600;
    background: linear-gradient(90deg, var(--light-text1), var(--secondary-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}

/* --- 演示视频部分 --- */
.demo-video-section { 
    padding: 6rem 1.5rem; 
    background: linear-gradient(to bottom, var(--dark-bg1), var(--dark-bg2));
    position: relative;
}
.demo-video-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(
        ellipse at top right,
        hsla(var(--accent-hue), 70%, 40%, 0.15) 0%,
        transparent 60%
    );
    z-index: 0;
}
.demo-video-section > * {
    position: relative;
    z-index: 1;
}
.video-wrapper {
    max-width: 1000px; margin: 2rem auto 0; border-radius: var(--radius-lg);
    overflow: hidden; 
    box-shadow: 0 25px 60px rgba(0,0,0,0.4), 0 0 0 1px var(--border-color);
    border: 2px solid transparent;
    transition: border-color var(--transition-smooth), box-shadow var(--transition-smooth);
    position: relative;
}
.video-wrapper::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: var(--radius-lg);
    border: 1px solid var(--primary);
    opacity: 0.3;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}
.video-wrapper:hover {
    border-color: var(--border-glow);
    box-shadow: 0 30px 70px rgba(0,0,0,0.5), 0 0 30px var(--neon-glow-primary);
}
.video-wrapper:hover::after {
    opacity: 0.7;
}
.video-wrapper video { 
    display: block; width: 100%; height: auto; 
    aspect-ratio: 16 / 9; 
    background-color: var(--dark-bg3);
    transition: var(--transition-smooth);
}
.video-wrapper:hover video {
    transform: scale(1.01);
}

/* --- 社区部分 --- */
.community-section { 
    padding: 6rem 1.5rem; 
    background: linear-gradient(to bottom, var(--dark-bg2), var(--dark-bg1));
    position: relative;
}
.community-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(
        ellipse at bottom left,
        hsla(var(--primary-hue), 70%, 40%, 0.15) 0%,
        transparent 60%
    );
    z-index: 0;
}
.community-section > * {
    position: relative;
    z-index: 1;
}
.community-cards-container { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); 
    gap: 2.5rem; 
    margin-top: 2rem;
}
.community-card { text-align: center; }
.community-btn {
    padding: 0.8rem 1.4rem; 
    background: transparent; 
    color: var(--primary-light);
    border: 2px solid var(--primary); 
    border-radius: var(--radius-md);
    font-size: 1rem; 
    font-weight: 600; 
    cursor: pointer;
    transition: var(--transition-swift); 
    display: inline-flex;
    align-items: center; 
    gap: 0.5rem; 
    text-decoration: none; 
    margin-top: 1.5rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}
.community-btn:hover { 
    background: hsla(var(--primary-hue), 80%, 55%, 0.15); 
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.25), var(--neon-glow-primary);
}
.community-btn i { margin-right: 0.4em; }

/* --- 页脚 --- */
.site-footer {
    background: var(--dark-bg1); 
    color: var(--light-text3);
    padding: 5rem 1.5rem 2.5rem; 
    border-top: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}
.site-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(
        ellipse at top center,
        hsla(var(--primary-hue), 60%, 20%, 0.1) 0%,
        transparent 70%
    );
    z-index: 0;
}
.site-footer > * {
    position: relative;
    z-index: 1;
}
.footer-main { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); 
    gap: 3rem; 
    margin-bottom: 4rem; 
}
.footer-about .logo.footer-logo { 
    margin-bottom: 1rem; 
    display: flex; 
    align-items: center; 
}
.footer-about .logo.footer-logo .logo-icon-main { 
    width: 2rem; 
    height: 2rem; 
    margin-right: 0.6rem;
}
.footer-about p { 
    font-size: 1rem; 
    line-height: 1.8; 
    margin-top: 1rem;
    color: var(--light-text2);
}
.footer-contact { margin-top: 1.5rem; }
.footer-contact a { 
    display: inline-flex; 
    align-items: center; 
    gap: 0.6rem; 
    color: var(--light-text2);
    padding: 0.5rem 0;
    transition: var(--transition-swift);
}
.footer-contact a:hover { 
    color: var(--primary-light);
    transform: translateX(5px);
}
.footer-contact i { 
    color: var(--primary);
    font-size: 1.2rem;
}
.footer-links-group h4 {
    font-size: 1.25rem; 
    font-weight: 600; 
    color: var(--light-text1);
    margin-bottom: 1.5rem; 
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
    background: linear-gradient(90deg, var(--light-text1), var(--primary-light));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.footer-links-group ul { 
    list-style: none;
    padding-left: 0.5rem;
}
.footer-links-group li { margin-bottom: 0.8rem; }
.footer-links-group a { 
    color: var(--light-text2); 
    font-size: 1rem;
    display: inline-block;
    padding: 0.3rem 0;
    transition: var(--transition-swift);
    position: relative;
}
.footer-links-group a::before {
    content: '→';
    position: absolute;
    left: -1.2rem;
    opacity: 0;
    transform: translateX(-10px);
    transition: var(--transition-swift);
    color: var(--primary);
}
.footer-links-group a:hover { 
    color: var(--primary-light); 
    text-decoration: none;
    transform: translateX(10px);
}
.footer-links-group a:hover::before {
    opacity: 1;
    transform: translateX(0);
}

.footer-bottom {
    padding-top: 2.5rem; 
    border-top: 1px solid var(--border-color);
    display: flex; 
    flex-direction: column; 
    align-items: center; 
    text-align: center; 
    gap: 1.5rem;
}
.copyright { 
    font-size: 1rem;
    color: var(--light-text2);
}
.social-icons { 
    display: flex; 
    gap: 1.5rem;
}
.social-icons a { 
    color: var(--light-text3); 
    font-size: 1.5rem; 
    transition: var(--transition-swift);
    width: 3rem;
    height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: hsla(var(--primary-hue), 30%, 15%, 0.3);
    border: 1px solid var(--border-color);
}
.social-icons a:hover { 
    color: var(--primary-light); 
    transform: translateY(-5px);
    background: hsla(var(--primary-hue), 40%, 20%, 0.4);
    border-color: var(--primary);
    box-shadow: var(--neon-glow-primary);
}


/* --- 动画元素 --- */
.animated-element { opacity: 0; transform: translateY(35px); }
.animate-in.animated-element {
    opacity: 1; transform: translateY(0);
    transition: opacity 0.7s var(--transition-smooth) var(--animation-delay, 0s),
                transform 0.7s var(--transition-smooth) var(--animation-delay, 0s);
}

/* --- 响应式设计 --- */
@media (max-width: 992px) {
    .container { padding: 0 1.5rem; }
    .navbar { padding: 1rem 1.5rem; }
    .navbar.scrolled { padding: 0.75rem 1.5rem; }
    .nav-links-container {
        position: fixed; top: var(--header-height); left: 0; right: 0;
        background: hsla(var(--primary-hue), 15%, 6%, 0.98);
        flex-direction: column; align-items: center;
        padding: 2.5rem 1.5rem; gap: 0.5rem;
        height: calc(100vh - var(--header-height));
        transform: translateX(100%);
        transition: transform var(--transition-smooth);
        overflow-y: auto;
        box-shadow: -5px 0 25px rgba(0,0,0,0.3);
        backdrop-filter: blur(15px);
    }
    .nav-links-container.active { transform: translateX(0); }
    .nav-links { flex-direction: column; gap: 0; width: 100%; }
    .nav-links li { width: 100%; text-align: center; }
    .nav-links a { 
        display: block; 
        padding: 1.25rem; 
        font-size: 1.2rem; 
        border-bottom: 1px solid var(--border-color);
    }
    .nav-links li:last-child a { border-bottom: none; }
    .navbar .github-btn { margin-top: 1.5rem; padding: 0.8rem 2rem; }
    .menu-btn { display: block; }

    .workflow-timeline::before { left: 20px; transform: none; }
    .workflow-item { width: 100%; left: 0 !important; padding-left: 60px !important; padding-right: 0 !important; text-align: left !important; }
    .workflow-item:nth-child(odd) .workflow-icon,
    .workflow-item:nth-child(even) .workflow-icon { left: -15px; transform: none; width: 60px; height: 60px; font-size: 1.5rem;}
    .workflow-item .workflow-content { padding-left: 1.5rem; padding-top: 2.5rem; }
    .react-workflow .workflow-step-num { left: 1.25rem; top: 1rem; }
}
@media (max-width: 768px) {
    .hero h1 { font-size: clamp(2.2rem, 7vw, 3rem); }
    .hero .subtitle { font-size: clamp(1.05rem, 3.5vw, 1.2rem); }
    .section-title { font-size: clamp(2rem, 6vw, 2.5rem); }
    section .section-subtitle { font-size: clamp(1rem, 3vw, 1.1rem); margin-bottom: 3rem; }
    .features-grid, .tech-grid, .community-cards-container { gap: 2rem; }
    .feature-card, .tech-item, .community-card, .workflow-item .workflow-content { padding: 2rem; }
    .footer-main { grid-template-columns: 1fr; }
    .footer-links-group h4 { text-align: left; }
    .footer-about p { margin-bottom: 1.5rem; }
}
@media (max-width: 480px) {
    .cta-buttons { flex-direction: column; width: 100%; }
    .primary-btn, .secondary-btn { width: 100%; justify-content: center; }
    .hero-stats { 
        gap: 1.5rem; 
        flex-direction: column;
        padding: 2rem 1.5rem;
    }
    .stat-value { font-size: clamp(2.2rem, 6vw, 2.7rem); }
    .primary-btn, .secondary-btn { padding: 0.9rem 1.5rem; font-size: 1rem; }
    
    .navbar { padding: 0.75rem 1rem; }
    .navbar.scrolled { padding: 0.5rem 1rem; }
    .logo { font-size: 1.5rem; }
    .logo-icon-main { width: 1.8rem; height: 1.8rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important; animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important; scroll-behavior: auto !important;
    animation-name: none !important;
  }
  .hero-abstract-svg, .hero-shape, .pulse-effect { animation: none !important; }
  .digital-rain canvas { display: none; }
  #particles-js-custom canvas { display: none; }
}

/* 额外的辅助类 */
.desktop-only {
    display: inline-block;
}
@media (max-width: 768px) {
    .desktop-only {
        display: none;
    }
}

/* 返回顶部按钮 */
.back-to-top-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-smooth);
    z-index: 99;
}

.back-to-top-btn:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.4), var(--neon-glow-primary);
}

.back-to-top-btn.show {
    opacity: 1;
    visibility: visible;
}

@media (max-width: 768px) {
    .back-to-top-btn {
        bottom: 20px;
        right: 20px;
        width: 45px;
        height: 45px;
    }
}

.react-workflow .workflow-step-num {
    position: absolute;
    top: 1.2rem;
    left: 1.8rem;
    background: var(--accent-dark);
    color: var(--light-text1);
    padding: 0.3rem 0.8rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem; /* 缩小字体 */
    font-weight: 700;
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    box-shadow: 0 3px 10px rgba(0,0,0,0.3);
    z-index: 3; /* 确保标签在顶层 */
    width: auto; /* 自适应宽度 */
}

.workflow-item h3 { 
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    margin-top: 1rem; /* 为步骤标签留出更多空间 */
    background: linear-gradient(90deg, var(--light-text1), var(--secondary-light));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    position: relative; /* 确保正确定位 */
    z-index: 2;
}

/* --- 修复技术引擎部分排版 --- */
.tech-grid-condensed {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2.5rem;
    margin-top: 3rem;
    max-width: 1500px; /* 控制整体宽度 */
    margin-left: auto;
    margin-right: auto;
}

.tech-grid-condensed .tech-item {
    flex: 0 0 280px; /* 固定宽度，不拉伸 */
    max-width: 280px; 
    min-width: 0; /* 允许收缩 */
    margin-bottom: 1rem;
}

/* 确保5个元素在一行显示的调整 */
@media (min-width: 1501px) {
    .tech-grid-condensed {
        justify-content: center;
        max-width: 1500px;
    }
}

/* 4个元素 */
@media (min-width: 1201px) and (max-width: 1500px) {
    .tech-grid-condensed {
        max-width: 1200px;
        margin-left: auto;
        margin-right: auto;
    }
}

/* 3个元素 */
@media (min-width: 901px) and (max-width: 1200px) {
    .tech-grid-condensed {
        max-width: 900px;
        margin-left: auto;
        margin-right: auto;
    }
}

/* 2个元素 */
@media (min-width: 601px) and (max-width: 900px) {
    .tech-grid-condensed {
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
    }
}