@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
    --primary-color: #4361ee;
    --secondary-color: #3f37c9;
    --accent-color: #f72585;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --success-color: #4cc9f0;
    --warning-color: #fca311;
}

body {
    font-family: 'Noto Sans SC', sans-serif;
    scroll-behavior: smooth;
}

.gradient-bg {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

.accent-gradient {
    background: linear-gradient(135deg, var(--accent-color), #7209b7);
}

.card-hover {
    transition: all 0.3s ease;
}

.card-hover:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    transition: all 0.3s ease;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(67, 97, 238, 0.4);
}

.btn-accent {
    background: linear-gradient(135deg, var(--accent-color), #7209b7);
    transition: all 0.3s ease;
}

.btn-accent:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(247, 37, 133, 0.4);
}

.feature-icon {
    transition: all 0.3s ease;
}

.feature-card:hover .feature-icon {
    transform: scale(1.1);
    color: var(--accent-color);
}

.faq-item {
    transition: all 0.3s ease;
}

.faq-item.active {
    background-color: rgba(67, 97, 238, 0.05);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 200px;
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: white;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.chat-container {
    position: fixed;
    bottom: 70px;
    right: 20px;
    width: 300px;
    height: 400px;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    z-index: 999;
    display: none;
    overflow: hidden;
}

.chat-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 15px;
    font-weight: bold;
}

.chat-messages {
    height: 300px;
    overflow-y: auto;
    padding: 15px;
}

.chat-input {
    display: flex;
    padding: 10px;
    border-top: 1px solid #eee;
}

.message {
    margin-bottom: 10px;
    padding: 10px;
    border-radius: 10px;
    max-width: 80%;
}

.user-message {
    background-color: #e9ecef;
    margin-left: auto;
}

.bot-message {
    background-color: #4361ee;
    color: white;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .desktop-nav {
        display: none;
    }

    .bottom-nav {
        display: flex;
    }
}

@media (min-width: 769px) {
    .desktop-nav {
        display: flex;
    }

    .bottom-nav {
        display: none;
    }

    .chat-container {
        width: 350px;
        height: 500px;
    }

    .chat-messages {
        height: 400px;
    }
}

/* 加载动画 */
.loading {
    display: inline-block;
    position: relative;
    width: 80px;
    height: 80px;
}

.loading div {
    position: absolute;
    top: 33px;
    width: 13px;
    height: 13px;
    border-radius: 50%;
    background: var(--primary-color);
    animation-timing-function: cubic-bezier(0, 1, 1, 0);
}

.loading div:nth-child(1) {
    left: 8px;
    animation: loading1 0.6s infinite;
}

.loading div:nth-child(2) {
    left: 8px;
    animation: loading2 0.6s infinite;
}

.loading div:nth-child(3) {
    left: 32px;
    animation: loading2 0.6s infinite;
}

.loading div:nth-child(4) {
    left: 56px;
    animation: loading3 0.6s infinite;
}

@keyframes loading1 {
    0% {
        transform: scale(0);
    }
    100% {
        transform: scale(1);
    }
}

@keyframes loading3 {
    0% {
        transform: scale(1);
    }
    100% {
        transform: scale(0);
    }
}

@keyframes loading2 {
    0% {
        transform: translate(0, 0);
    }
    100% {
        transform: translate(24px, 0);
    }
}

/* 流量卡动画 */
.card-animation {
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-10px);
    }
    100% {
        transform: translateY(0px);
    }
}