:root {
    --bg-dark: #050507;
    --text-main: #ffffff;
    --text-muted: #a0a0b0;
    --accent-primary: #7000ff; /* 赛博紫 */
    --accent-secondary: #00f0ff; /* 霓虹蓝 */
    --glass-bg: rgba(20, 20, 25, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --card-hover: rgba(255, 255, 255, 0.05);
    
    --font-heading: 'Space Grotesk', sans-serif;
    --font-body: 'Inter', sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-body);
    line-height: 1.7;
    overflow-x: hidden;
    min-height: 100vh;
}

a { text-decoration: none; color: inherit; transition: color 0.3s; }

/* --- 动态背景 --- */
.ambient-light {
    position: fixed;
    border-radius: 50%;
    filter: blur(100px);
    z-index: -2;
    opacity: 0.5;
    animation: float 10s infinite ease-in-out;
}
.ambient-light.one { top: -10%; left: -10%; width: 50vw; height: 50vw; background: radial-gradient(circle, var(--accent-primary), transparent); }
.ambient-light.two { bottom: -10%; right: -10%; width: 60vw; height: 60vw; background: radial-gradient(circle, #2d005f, transparent); animation-delay: -5s; }

.grid-overlay {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background-image: linear-gradient(var(--glass-border) 1px, transparent 1px), linear-gradient(90deg, var(--glass-border) 1px, transparent 1px);
    background-size: 50px 50px; z-index: -1; opacity: 0.1;
    mask-image: radial-gradient(circle at center, black 40%, transparent 100%);
}

@keyframes float { 0%, 100% { transform: translate(0, 0); } 50% { transform: translate(30px, 50px); } }

/* --- 导航栏 --- */
nav {
    display: flex; justify-content: space-between; align-items: center;
    padding: 1.5rem 3rem;
    background: rgba(5, 5, 7, 0.8); backdrop-filter: blur(10px);
    position: sticky; top: 0; z-index: 100;
    border-bottom: 1px solid var(--glass-border);
}
.logo { font-family: var(--font-heading); font-weight: 700; font-size: 1.5rem; letter-spacing: -0.5px; background: linear-gradient(90deg, #fff, var(--accent-secondary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.nav-links { display: flex; gap: 2rem; align-items: center; }
.nav-links a { color: var(--text-muted); font-size: 0.95rem; font-weight: 500; }
.nav-links a:hover { color: var(--text-main); text-shadow: 0 0 10px var(--accent-secondary); }
.lang-btn { padding: 6px 16px; border: 1px solid var(--glass-border); border-radius: 20px; font-size: 0.85rem; transition: all 0.3s; }
.lang-btn:hover { border-color: var(--accent-secondary); color: var(--accent-secondary); background: rgba(0, 240, 255, 0.1); }

/* --- Hero --- */
.hero { padding: 6rem 2rem; text-align: center; position: relative; }
.hero h1 {
    font-family: var(--font-heading); font-size: 4rem; font-weight: 700; line-height: 1.1; margin-bottom: 1.5rem;
    background: linear-gradient(135deg, #fff 0%, #a5a5a5 100%); -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero p { font-size: 1.25rem; color: var(--text-muted); max-width: 800px; margin: 0 auto; font-weight: 300; }

/* --- overview (Project Intro) --- */
.container { max-width: 1100px; margin: 0 auto; padding: 2rem; }
.overview {
    background: var(--glass-bg); border: 1px solid var(--glass-border); border-radius: 24px; padding: 3rem; margin-bottom: 4rem;
    text-align: left; position: relative; overflow: hidden;
}
.overview::before {
    content: ''; position: absolute; top: 0; left: 0; width: 4px; height: 100%; background: linear-gradient(to bottom, var(--accent-primary), var(--accent-secondary));
}
.section-title { font-family: var(--font-heading); font-size: 2rem; margin-bottom: 1.5rem; display: flex; align-items: center; gap: 10px; }
.overview p { margin-bottom: 1rem; color: #d0d0d0; font-size: 1.05rem; }
.overview strong { color: var(--accent-secondary); font-weight: 600; }
.overview a {
    color: var(--accent-secondary);
    text-decoration: none;
    border-bottom: 1px solid rgba(0, 240, 255, 0.35);
    transition: color 0.2s ease, background-color 0.2s ease, box-shadow 0.2s ease;
}
.overview a:hover {
    color: #fff;
    background-color: rgba(0, 240, 255, 0.18);
    box-shadow: 0 0 10px rgba(0, 240, 255, 0.35);
}

/* --- Project Grid --- */
.project-card {
    background: rgba(255, 255, 255, 0.03); border: 1px solid var(--glass-border); border-radius: 20px; overflow: hidden; margin-bottom: 3rem;
    transition: transform 0.3s, box-shadow 0.3s;
}
.project-card:hover { transform: translateY(-5px); box-shadow: 0 10px 30px rgba(0,0,0,0.3); border-color: rgba(112, 0, 255, 0.3); }

.video-container {
    width: 100%; aspect-ratio: 16 / 9; background: #000; position: relative;
    display: flex; align-items: center; justify-content: center;
}
.video-placeholder-text { color: #555; font-family: var(--font-heading); letter-spacing: 1px; }
.video-container iframe { width: 100%; height: 100%; border: none; }

.card-content { padding: 2rem; }
.project-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 1rem; flex-wrap: wrap; gap: 10px; }
.project-title { font-family: var(--font-heading); font-size: 1.8rem; font-weight: 700; color: #fff; }
.project-badges { display: flex; gap: 8px; flex-wrap: wrap; }
.badge {
    padding: 4px 10px; border-radius: 6px; font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px;
    display: inline-flex; align-items: center; gap: 5px; color: #fff; opacity: 0.9; transition: opacity 0.2s;
}
.badge:hover { opacity: 1; }
.badge-publish { background: rgba(34, 197, 94, 0.2); color: #4ade80; border: 1px solid rgba(34, 197, 94, 0.3); }
.badge-project { background: rgba(0, 123, 255, 0.2); color: #66b0ff; border: 1px solid rgba(0, 123, 255, 0.3); }
.badge-arxiv { background: rgba(179, 27, 27, 0.2); color: #ff8a8a; border: 1px solid rgba(179, 27, 27, 0.3); }
.badge-github { background: rgba(255, 255, 255, 0.1); color: #fff; border: 1px solid rgba(255, 255, 255, 0.2); }
.badge-huggingface { background: rgba(255, 210, 30, 0.2); color: #FFD21E; border: 1px solid rgba(255, 210, 30, 0.3); }
.badge-modelscope { background: rgba(96, 77, 244, 0.2); color: #9b8aff; border: 1px solid rgba(96, 77, 244, 0.3); }

.project-desc { color: var(--text-muted); font-size: 1rem; margin-bottom: 1.5rem; line-height: 1.6; }

/* --- News --- */
.news-section { background: rgba(255, 255, 255, 0.02); border-radius: 20px; padding: 2rem; border: 1px solid var(--glass-border); margin-bottom: 3rem; }
.news-item { display: flex; gap: 1.5rem; padding: 1rem 0; border-bottom: 1px solid rgba(255, 255, 255, 0.05); }
.news-item:last-child { border-bottom: none; }
.news-date { min-width: 100px; font-family: var(--font-heading); color: var(--accent-secondary); font-weight: 600; }
.news-text { color: #ccc; }
.news-text a { color: var(--accent-primary); border-bottom: 1px solid rgba(112,0,255,0.3); }
.news-text a:hover { color: #fff; background: var(--accent-primary); }

footer { text-align: center; padding: 3rem 0; color: #666; font-size: 0.9rem; }

@media (max-width: 768px) {
    .hero h1 { font-size: 2.5rem; }
    .news-item { flex-direction: column; gap: 0.5rem; }
}