* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html { background-color: var(--bg); overscroll-behavior-y: none; }
body { margin: 0; padding: 0; overflow-x: hidden; background: transparent; font-family: -apple-system, system-ui, sans-serif; color: var(--text); }

/* 将容器放大，防止流体超出屏幕边缘被截断 */
.glass-bg-container { 
    position: fixed; 
    top: -50vh; left: -50vw; right: -50vw; bottom: -50vh; 
    width: 200vw; height: 200vh; 
    z-index: -2; overflow: hidden; 
    background: var(--bg); 
    transform: translateZ(0); 
}

/* 流体色块核心：超大模糊 + 色彩混合模式 */
.glass-blob { 
    position: absolute; 
    filter: blur(90px); 
    opacity: 0.55; 
    border-radius: 50%; 
    mix-blend-mode: multiply; /* 亮色模式下正片叠底，产生水彩交融感 */
    will-change: transform, border-radius;
}

[data-theme="dark"] .glass-blob { 
    opacity: 0.35; 
    mix-blend-mode: screen; /* 暗色模式下滤色，产生霓虹发光感 */
    filter: blur(120px); 
}

/* 谷歌四色：将体积放大，分配各自的动画 */
.blob-1 { 
    width: 60vw; height: 60vh; background: #4285F4; /* 蓝 */
    top: 10%; left: 10%; 
    animation: blob-flow-1 25s infinite alternate cubic-bezier(0.4, 0, 0.2, 1); 
}
.blob-2 { 
    width: 55vw; height: 55vh; background: #EA4335; /* 红 */
    bottom: 10%; right: 10%; 
    animation: blob-flow-2 28s infinite alternate cubic-bezier(0.4, 0, 0.2, 1); 
}
.blob-3 { 
    width: 65vw; height: 65vh; background: #FBBC05; /* 黄 */
    top: 20%; right: 20%; 
    animation: blob-flow-3 32s infinite alternate cubic-bezier(0.4, 0, 0.2, 1); 
}
.blob-4 { 
    width: 50vw; height: 50vh; background: #34A853; /* 绿 */
    bottom: 20%; left: 20%; 
    animation: blob-flow-4 26s infinite alternate cubic-bezier(0.4, 0, 0.2, 1); 
}

.glass-bg-overlay { 
    position: fixed; inset: -50%; 
    backdrop-filter: blur(40px); -webkit-backdrop-filter: blur(40px); 
    z-index: -1; background: rgba(255, 255, 255, 0.1); 
}
[data-theme="dark"] .glass-bg-overlay { background: rgba(17, 17, 25, 0.3); }