/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    min-height: 100vh;
    overflow: hidden;
}

/* 宇宙容器 */
.universe-container {
    position: fixed;
    width: 100vw;
    height: 100vh;
    background: radial-gradient(ellipse at bottom, #1B2735 0%, #090A0F 100%);
    overflow: hidden;
}

/* 星空背景 */
.stars {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: transparent url(../images/stars.png) repeat top center;
    z-index: 0;
    animation: move-stars 200s linear infinite;
}

.twinkling {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: transparent url(../images/twinkling.png) repeat top center;
    z-index: 1;
    animation: move-twinkle 200s linear infinite;
}

/* 内容区域 */
.content {
    position: relative;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 2rem;
    color: #fff;
}

/* 标题样式 */
.title {
    font-size: 4rem;
    font-weight: bold;
    margin-bottom: 3rem;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
    animation: title-glow 2s ease-in-out infinite alternate;
}

/* 菜单样式 */
.menu {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    max-width: 800px;
    width: 100%;
}

.menu-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    text-decoration: none;
    color: #fff;
    transition: all 0.3s ease;
}

.menu-item:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.15);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.2);
}

.menu-item .icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.menu-item .text {
    font-size: 1.2rem;
    font-weight: bold;
}

/* 动画定义 */
@keyframes move-stars {
    from { background-position: 0 0; }
    to { background-position: 10000px 0; }
}

@keyframes move-twinkle {
    from { background-position: 0 0; }
    to { background-position: 10000px 5000px; }
}

@keyframes title-glow {
    from {
        text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
    }
    to {
        text-shadow: 0 0 20px rgba(255, 255, 255, 0.8),
                     0 0 30px rgba(255, 255, 255, 0.6),
                     0 0 40px rgba(255, 255, 255, 0.4);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .title {
        font-size: 2.5rem;
    }

    .menu {
        grid-template-columns: 1fr;
    }

    .menu-item {
        padding: 1.5rem;
    }
}