/* 廉價 Flash 背景動畫 */
.flash-bg {
    background: radial-gradient(circle, #ff00ff, #00ffff, #ffff00, #ff0000);
    background-size: 400% 400%;
    animation: cheapFlash 1.5s ease infinite alternate;
    border: 10px inset #00ff00; /* 經典的 3D 凹陷邊框 */
}

@keyframes cheapFlash {
    0% { background-position: 0% 50%; filter: hue-rotate(0deg); }
    100% { background-position: 100% 50%; filter: hue-rotate(360deg); }
}

/* 閃爍的 Loading 文字 */
.flash-loading {
    font-family: "Comic Sans MS", cursive;
    color: #fff;
    text-shadow: 2px 2px #ff0000, -2px -2px #0000ff;
    animation: blinker 0.2s steps(2, start) infinite;
}