/* ==========================================
   全局变量：多彩科技风 (Colorful Tech)
   ========================================== */
:root {
    --bg-dark: #020714;
    --grid-color: rgba(0, 150, 255, 0.1);
    --glass-bg: rgba(16, 25, 48, 0.75);
    --neon-blue: #00e5ff;
    --neon-blue-glow: rgba(0, 229, 255, 0.5);
    --neon-orange: #ff8a00;
    --neon-orange-glow: rgba(255, 138, 0, 0.5);
    --neon-purple: #906cff;
    --text-main: #e8e8e8;
    --text-muted: #888;
}

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

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
}

/* ==========================================
   动态背景：多层叠加
   ========================================== */
#tech-background {
    position: fixed; top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: -1;
    background: 
        radial-gradient(ellipse at 50% -20%, rgba(0, 100, 255, 0.3) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 120%, rgba(255, 100, 0, 0.15) 0%, transparent 50%),
        var(--bg-dark);
}

.grid-lines {
    position: absolute;
    width: 200%; height: 200%;
    top: -50%; left: -50%;
    background-image: 
        linear-gradient(to right, var(--grid-color) 1px, transparent 1px),
        linear-gradient(to bottom, var(--grid-color) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: moveGrid 20s linear infinite;
    transform: rotateX(60deg);
    transform-origin: center center;
}

@keyframes moveGrid {
    0% { transform: rotateX(60deg) translateY(0); }
    100% { transform: rotateX(60deg) translateY(50px); }
}

/* ==========================================
   鼠标跟随光效
   ========================================== */
.cursor-glow {
    position: fixed;
    width: 400px; height: 400px;
    background: radial-gradient(circle, rgba(0, 229, 255, 0.15) 0%, transparent 60%);
    border-radius: 50%;
    pointer-events: none;
    transform: translate(-50%, -50%);
    z-index: 9999;
    transition: opacity 0.3s;
}

/* ==========================================
   布局与容器
   ========================================== */
.container { width: 90%; max-width: 1200px; margin: 0 auto; padding: 20px 0; position: relative; z-index: 1; }
section { margin-bottom: 100px; }

h1, h2, h3 { font-family: 'Orbitron', sans-serif; font-weight: 700; }
h2 { font-size: 36px; text-align: center; margin-bottom: 50px; position: relative; }
h2::after {
    content: ''; width: 100px; height: 4px;
    background: linear-gradient(90deg, var(--neon-blue), var(--neon-orange));
    position: absolute; bottom: -15px; left: 50%; transform: translateX(-50%);
    border-radius: 2px;
}

/* ==========================================
   头部导航
   ========================================== */
header { display: flex; justify-content: space-between; align-items: center; padding: 20px 0; margin-bottom: 40px; border-bottom: 1px solid rgba(0, 229, 255, 0.2); }
.logo { font-size: 28px; font-family: 'Orbitron'; font-weight: 900; color: #fff; text-shadow: 0 0 10px var(--neon-blue), 0 0 20px var(--neon-blue); }
nav a { color: var(--text-main); text-decoration: none; margin-left: 30px; transition: .3s; position: relative; }
nav a::after { content: ''; position: absolute; width: 0; height: 2px; bottom: -5px; left: 0; background: var(--neon-orange); transition: width .3s; }
nav a:hover { color: var(--neon-orange); }
nav a:hover::after { width: 100%; }

/* ==========================================
   Hero 区域
   ========================================== */
.hero {
    text-align: center; padding: 140px 20px;
    background: var(--glass-bg); border-radius: 20px;
    border: 1px solid rgba(255,255,255,0.1); backdrop-filter: blur(10px);
    box-shadow: 0 0 60px rgba(0, 100, 255, 0.2);
    position: relative; overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute; top: -50%; left: -50%;
    width: 200%; height: 200%;
    background: radial-gradient(circle at 30% 30%, rgba(255, 138, 0, 0.1) 0%, transparent 30%),
                radial-gradient(circle at 70% 70%, rgba(0, 229, 255, 0.1) 0%, transparent 30%);
    animation: rotateBg 10s linear infinite;
    z-index: 0;
}
@keyframes rotateBg { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

.hero h1 { font-size: 68px; position: relative; z-index: 1; margin-bottom: 25px; }
.hero h1 span { background: linear-gradient(90deg, var(--neon-blue), var(--neon-orange)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero p { font-size: 20px; color: var(--text-muted); max-width: 700px; margin: 0 auto; position: relative; z-index: 1; line-height: 1.8; }

/* ==========================================
   功能卡片
   ========================================== */
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 30px; }
.feature-card {
    background: var(--glass-bg); padding: 30px; border-radius: 15px;
    border: 1px solid transparent; transition: .4s; backdrop-filter: blur(5px);
    position: relative;
}
.feature-card:hover { border-color: var(--neon-blue); transform: translateY(-10px); }
.feature-card h3 { color: var(--neon-blue); margin-bottom: 15px; font-size: 20px; }
.feature-card p { color: var(--text-muted); font-size: 14px; }
.feature-card::before {
    content: ''; position: absolute; top: 0; left: 0;
    width: 50px; height: 50px;
    background: linear-gradient(135deg, var(--neon-orange) 0%, transparent 70%);
    border-radius: 15px 0 100% 0;
    opacity: 0.5;
}

/* ==========================================
   下载列表（默认收缩）
   ========================================== */
.download-list { display: grid; gap: 20px; }
.download-item {
    background: var(--glass-bg); border-radius: 15px;
    border: 1px solid rgba(255,255,255,0.1); overflow: hidden;
}
.download-header {
    padding: 25px 30px; display: flex; justify-content: space-between; align-items: center;
    cursor: pointer; transition: background .3s;
}
.download-header:hover { background: rgba(255,255,255,0.05); }
.download-header h3 { font-size: 22px; }
.arrow { font-size: 24px; color: var(--neon-blue); transition: transform 0.4s; }
.download-detail {
    max-height: 0; overflow: hidden; transition: max-height 0.5s ease-out, padding 0.5s ease-out;
}
.download-detail.active { max-height: 400px; padding: 20px 30px; border-top: 1px solid rgba(0,229,255,0.2); }
.download-detail p { margin-bottom: 15px; color: var(--text-muted); }
.info-tags span { display: none; } /* 隐藏版本和大小 */
.download-detail .btn-group { margin-top:20px; }
.download-detail .btn { padding: 10px 25px; font-size: 14px; }
.btn {
    padding: 15px 40px; border-radius: 50px; text-decoration: none; font-weight: bold;
    font-family: 'Orbitron'; letter-spacing: 1px;
    transition: all 0.4s ease; cursor: pointer; border: none; position: relative; overflow: hidden; z-index: 1;
}
.btn-primary {
    background: linear-gradient(90deg, var(--neon-blue), var(--neon-orange));
    color: #000; box-shadow: 0 0 20px var(--neon-blue-glow);
}
.btn-primary:hover { transform: scale(1.05); box-shadow: 0 0 40px var(--neon-orange-glow); }

/* ==========================================
   联系社群区域
   ========================================== */
.contact-section { text-align:center; }
.contact-section p { color: var(--text-muted); margin-bottom: 40px; }
.btn-outline {
    background: transparent; color: var(--neon-blue);
    border: 2px solid var(--neon-blue); box-shadow: 0 0 10px rgba(0, 229, 255, 0.3);
}
.btn-outline:hover { background: rgba(0, 229, 255, 0.1); border-color: var(--neon-orange); color: var(--neon-orange); }

/* ==========================================
   页脚
   ========================================== */
footer { text-align: center; padding: 40px 0; border-top: 1px solid rgba(255,255,255,0.1); color: var(--text-muted); font-size: 14px; margin-top: 60px; }
footer a { color: var(--neon-blue); text-decoration: none; }