#install-guide-btn {
    position: fixed;
    right: 20px;
    top: 36%;
    z-index: 1000;
    color: white;
    font-size: 16px;
    font-weight: bold;
    text-align: center;
    padding: 10px 5px;
    border-radius: 8px;
    cursor: pointer;
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    width: 50px;
    text-decoration: none;
    user-select: none;
}
.blink-button {
    animation: colorChange 4s infinite;
}
@keyframes colorChange {
    0% { background-color: yellow; color: #333; }
    50% { background-color: red; color: white; }
    100% { background-color: yellow; color: #333; }
}
#guide-modal-mask {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.7);
    z-index: 2000;
    display: none;
    justify-content: center;
    align-items: center;
    transition: opacity 0.3s ease;
    opacity: 0;
}
#guide-modal-content {
    position: relative;
    width: 80%;
    max-width: 400px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,0.5);
    transform: scale(0.9);
    transition: transform 0.3s ease;
}
#guide-modal-img {
    width: 100%;
    height: auto;
    display: block;
}
#guide-modal-close {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 30px;
    height: 30px;
    background: rgba(0,0,0,0.5);
    color: white;
    border-radius: 50%;
    border: none;
    font-size: 18px;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0;
    transition: background-color 0.2s ease;
}
#guide-modal-close:hover {
    background: rgba(255, 0, 0, 0.7);
}
#guide-modal-mask.active {
    display: flex;
    opacity: 1;
}
#guide-modal-mask.active #guide-modal-content {
    transform: scale(1);
}
.enter-btn {
    flex: 1;
    height: 40px;
    background: transparent;
    border: 2px solid rgba(255, 255, 255, 0.8);
    color: #fff;
    border-radius: 20px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}
.enter-btn:hover {
    border-color: rgba(255, 255, 255, 1);
    color: #ffffff;
    background: rgba(255, 255, 255, 0.1);
}