.zalo-hotline {
    position: fixed;
    right: 12px;
    bottom: 90px;
    z-index: 9999;
    display: flex;
    flex-direction: column-reverse;
    align-items: center;
    animation: fadeInUp 0.5s ease;
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(40px); }
    to { opacity: 1; transform: translateY(0); }
}
.zalo-main-button {
    position: relative;
}
.zalo-main-button::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100%;
    height: 100%;
    background: rgba(0, 136, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    z-index: 0;
    animation: wave-pulse 2.5s ease-out infinite;
}
@keyframes wave-pulse {
    0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.5;
    }
    70% {
        transform: translate(-50%, -50%) scale(1.6);
        opacity: 0.2;
    }
    100% {
        transform: translate(-50%, -50%) scale(2.1);
        opacity: 0;
    }
}
.zalo-main-button img {
    position: relative;
    z-index: 1;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    box-shadow: 0 8px 20px rgba(0,0,0,.25);
    cursor: pointer;
    transition: transform .3s, box-shadow .3s;
}
.zalo-main-button img:hover {
    transform: scale(1.1);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
}
.zalo-options {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    opacity: 0;
    transform: translateY(20px);
    transition: all .3s ease;
    pointer-events: none;
}
.zalo-options.active {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}
.zalo-option {
    width: 52px;
    height: 52px;
    background: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 6px 16px rgba(0,0,0,.2);
    cursor: pointer;
    transition: transform .25s ease, background .25s;
}
.zalo-option:hover {
    transform: scale(1.1);
    background: #f2f2f2;
}
.zalo-option img {
    width: 28px;
    height: 28px;
    object-fit: contain;
    transition: transform 0.3s;
}
.zalo-option img:hover {
    transform: rotate(10deg);
}