body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: #000;
    font-family: 'Noto Sans SC', sans-serif;
    color: #fff;
}

#canvas-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2;
    pointer-events: none;
    /* 让鼠标事件穿透到 Canvas */
}

.top-nav {
    position: absolute;
    top: 2rem;
    left: 2rem;
    pointer-events: auto;
}

.back-btn {
    text-decoration: none;
    color: rgba(255, 255, 255, 0.6);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    letter-spacing: 2px;
    transition: color 0.3s;
}

.back-btn:hover {
    color: #fff;
}

.back-btn .icon {
    font-size: 1.2rem;
}

.overlay-info {
    position: absolute;
    bottom: 10%;
    left: 5%;
    max-width: 400px;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s ease;
    pointer-events: auto;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(10px);
    padding: 2rem;
    border-left: 2px solid #fff;
}

.overlay-info.active {
    opacity: 1;
    transform: translateY(0);
}

.site-title {
    font-size: 2.5rem;
    font-weight: 100;
    margin: 0 0 1rem 0;
    letter-spacing: 2px;
}

.site-desc {
    font-size: 0.9rem;
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 2rem;
}

.visit-btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: #fff;
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 3px;
    transition: all 0.3s;
}

.visit-btn:hover {
    background: #fff;
    color: #000;
}

.instruction {
    position: absolute;
    bottom: 2rem;
    width: 100%;
    text-align: center;
    font-size: 0.7rem;
    letter-spacing: 4px;
    color: rgba(255, 255, 255, 0.3);
    pointer-events: none;
}