* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Segoe UI", sans-serif;
}

body {
    overflow: hidden;
    height: 100vh;
    background: linear-gradient(120deg, #4a00e0, #8e2de2, #00c6ff, #0072ff);
    background-size: 400% 400%;
    animation: gradientMove 12s ease infinite;
}

/* 动态渐变背景动画 */
@keyframes gradientMove {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* 粒子 canvas 层 */
#particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1;
}

.container {
    position: relative;
    z-index: 2;
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: white;
}

/* 主标题动画 */
.title {
    font-size: 60px;
    font-weight: bold;
    letter-spacing: 2px;
    animation: float 4s ease-in-out infinite;
}

/* 浮动动画 */
@keyframes float {
    0% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
    100% { transform: translateY(0); }
}

/* 副标题淡入动画 */
.subtitle {
    margin-top: 15px;
    font-size: 20px;
    opacity: 0;
    animation: fadeIn 3s forwards 1.5s;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 炫酷发光按钮 */
.btn {
    margin-top: 40px;
    padding: 14px 38px;
    font-size: 20px;
    color: white;
    text-decoration: none;
    border-radius: 50px;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(5px);
    box-shadow: 0 0 12px rgba(255,255,255,0.3);
    transition: all 0.35s;
}

.btn:hover {
    box-shadow: 0 0 25px rgba(255,255,255,0.9);
    transform: scale(1.08);
}
/* 底部备案 + 版权 */
.footer {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    z-index: 3;
    color: rgba(255,255,255,0.85);
    font-size: 15px;
    line-height: 1.6;
}

.footer .beian {
    color: rgba(255,255,255,0.9);
    text-decoration: none;
    transition: 0.3s;
}

.footer .beian:hover {
    text-shadow: 0 0 8px rgba(255,255,255,0.9);
    color: #fff;
}

.footer p {
    margin-top: 4px;
    font-size: 13px;
    opacity: 0.85;
}
/* 备案文字整体行 */
.beian-line {
    margin-bottom: 6px;
}

/* 公安备案那行特殊处理 */
.gongan-line a.gongan {
    display: inline-flex;
    align-items: center;
    gap: 6px;                    /* 图标和文字间距 */
    color: rgba(255,255,255,0.9);
    text-decoration: none;
}

.gongan-icon {
    height: 16px;                /* 标准公安备案图标高度 */
    width: auto;
    vertical-align: middle;
}

/* 悬停效果跟 ICP 保持一致 */
.gongan-line a:hover {
    text-shadow: 0 0 8px rgba(255,255,255,0.9);
    color: #fff;
}

/* 移动端稍微调小一点 */
@media (max-width: 768px) {
    .gongan-icon {
        height: 15px;
    }
    .footer {
        font-size: 14px;
    }
}