.comment-item {
    position: relative;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.comment-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.reply-btn {
    position: relative;
    overflow: hidden;
}

.reply-btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(0,0,0,0.1);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.3s, height 0.3s;
}

.reply-btn:active::after {
    width: 200px;
    height: 200px;
}

.reply-form-container {
    transform-origin: top center;
    animation: slideDown 0.3s ease-out forwards;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.reply-content {
    border: 1px solid #ddd;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.reply-content:focus {
    border-color: #007bff;
    box-shadow: 0 0 0 2px rgba(0,123,255,0.25);
    outline: none;
}

.button-group button {
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.button-group button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
    z-index: -1;
}

.button-group button:hover::before {
    left: 100%;
}

/* 美化滚动条 */
.comment-list::-webkit-scrollbar {
    width: 8px;
}

.comment-list::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

.comment-list::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

.comment-list::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .reply-form-container {
        padding: 10px;
    }
    
    .button-group button {
        padding: 0.25rem 0.75rem;
        font-size: 0.75rem;
    }
}