* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    background-color: #f0f0f0;
    color: #333;
    padding-bottom: 80px;
}

/* 顶部横幅 */
.top-banner {
    background: linear-gradient(135deg, #d32f2f 0%, #c62828 100%);
    padding: 30px 20px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.top-banner::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: shimmer 3s infinite;
}

@keyframes shimmer {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(10%, 10%); }
}

.banner-text {
    color: white;
    font-size: 18px;
    margin-bottom: 10px;
    position: relative;
    z-index: 1;
}

.banner-highlight {
    color: #ffeb3b;
    font-size: 22px;
    font-weight: bold;
    position: relative;
    z-index: 1;
}

.banner-highlight .number {
    font-size: 28px;
    font-weight: bold;
}

/* 聊天容器 */
.chat-container {
    padding: 20px 15px;
    max-width: 800px;
    margin: 0 auto;
    min-height: calc(100vh - 200px);
}

/* 消息组 */
.message-group {
    display: flex;
    align-items: flex-start;
    margin-bottom: 20px;
    opacity: 0;
    animation: fadeIn 0.5s forwards;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message-group.right {
    flex-direction: row-reverse;
}

.avatar {
    width: 40px;
    height: 40px;
    border-radius: 5px;
    overflow: hidden;
    flex-shrink: 0;
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.message-content {
    margin: 0 10px;
    max-width: 70%;
}

.message-group.right .message-content {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.sender-name {
    font-size: 13px;
    color: #888;
    margin-bottom: 5px;
}

.message-bubble {
    background-color: white;
    padding: 12px 15px;
    border-radius: 8px;
    line-height: 1.6;
    font-size: 15px;
    word-wrap: break-word;
}

.message-bubble.left {
    border-top-left-radius: 0;
}

.message-bubble.right {
    background-color: #95ec69;
    border-top-right-radius: 0;
}

/* 选项按钮组 */
.options-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin: 20px 0;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeIn 0.5s 0.3s forwards;
}

.option-btn {
    background-color: #d32f2f;
    color: white;
    border: none;
    padding: 12px 35px;
    border-radius: 25px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s;
    min-width: 100px;
}

.option-btn:hover {
    background-color: #b71c1c;
    transform: scale(1.05);
}

.option-btn:active {
    transform: scale(0.95);
}

.option-btn.selected {
    background-color: #1976d2;
}

/* 双按钮组 */
.dual-options {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin: 20px 0;
    opacity: 0;
    animation: fadeIn 0.5s 0.3s forwards;
}

.dual-btn {
    background-color: #d32f2f;
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 25px;
    font-size: 15px;
    cursor: pointer;
    transition: all 0.3s;
}

.dual-btn.secondary {
    background-color: #d32f2f;
}

.dual-btn:hover {
    transform: scale(1.05);
}

/* 底部按钮 */
.bottom-action {
    position: fixed;
    bottom: 50px;
    left: 0;
    right: 0;
    padding: 15px;
    background: linear-gradient(to top, rgba(240,240,240,1) 0%, rgba(240,240,240,0.95) 50%, rgba(240,240,240,0) 100%);
    display: flex;
    justify-content: center;
}

.primary-btn {
    background: linear-gradient(135deg, #d32f2f 0%, #b71c1c 100%);
    color: white;
    border: none;
    padding: 15px 60px;
    border-radius: 30px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(211, 47, 47, 0.4);
    transition: all 0.3s;
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(211, 47, 47, 0.5);
}

.primary-btn:active {
    transform: translateY(0);
}

/* 页脚 */
.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: white;
    padding: 12px;
    text-align: center;
    font-size: 12px;
    color: #999;
    border-top: 1px solid #e0e0e0;
}

.footer a {
    color: #1976d2;
    text-decoration: none;
}

/* 隐藏类 */
.hidden {
    display: none !important;
}

/* 响应式设计 */
@media (max-width: 600px) {
    .message-content {
        max-width: 80%;
    }
    
    .option-btn {
        padding: 10px 25px;
        font-size: 14px;
        min-width: 80px;
    }
    
    .banner-text {
        font-size: 16px;
    }
    
    .banner-highlight {
        font-size: 20px;
    }
    
    .banner-highlight .number {
        font-size: 24px;
    }
}