body {
    font-family: 'Roboto', sans-serif;
    background-color: #1a1a1a;
    color: #e0e0e0;
    margin: 0;
    line-height: 1.6;
}

#particles-js {
    position: fixed;
    width: 100%;
    height: 100%;
    z-index: -1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 40px;
    background-color: rgba(26, 26, 26, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #333;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: #4dd0e1;
}

.logo i {
    margin-right: 10px;
}

.contact-btn {
    background-color: #4dd0e1;
    color: #1a1a1a;
    padding: 8px 16px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    transition: background-color 0.3s;
}

.contact-btn:hover {
    background-color: #26c6da;
}

.welcome-section {
    text-align: center;
    padding: 60px 0;
}

.welcome-section h1 {
    font-size: 48px;
    color: #fff;
    margin-bottom: 10px;
}

.welcome-section p {
    font-size: 18px;
    color: #bdbdbd;
}

.features-section {
    display: flex;
    justify-content: space-around;
    gap: 20px;
    padding: 40px 0;
}

.feature-box {
    background-color: #2a2a2a;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    flex: 1;
    border: 1px solid #333;
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-box:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px rgba(77, 208, 225, 0.1);
}

.feature-box i {
    font-size: 40px;
    color: #4dd0e1;
    margin-bottom: 20px;
}

.feature-box h3 {
    font-size: 22px;
    color: #fff;
    margin-bottom: 10px;
}

.chat-container {
    background-color: #2a2a2a;
    border-radius: 10px;
    padding: 30px;
    margin: 40px auto;
    max-width: 900px;
    border: 1px solid #333;
}

.chat-messages {
    height: 300px;
    overflow-y: auto;
    margin-bottom: 20px;
    padding-right: 10px;
}

.message {
    display: flex;
    margin-bottom: 20px;
}

.message.user {
    justify-content: flex-end;
}

.message.bot {
    justify-content: flex-start;
}

.message.user i {
    order: 2;
    margin-left: 15px;
    margin-right: 0;
}

.message i {
    font-size: 24px;
    margin-right: 15px;
    color: #4dd0e1;
}

.message-content p {
    margin: 0;
}

.timestamp {
    font-size: 12px;
    color: #888;
    margin-top: 5px;
}

.chat-input-area {
    display: flex;
    align-items: center;
    background-color: #3c3c3c;
    border-radius: 8px;
    padding: 5px 10px;
}

#chat-input {
    flex: 1;
    background: transparent;
    border: none;
    color: #e0e0e0;
    font-size: 16px;
    padding: 10px;
    resize: none;
}

#chat-input:focus {
    outline: none;
}

#send-btn {
    background: #4dd0e1;
    border: none;
    border-radius: 5px;
    color: #1a1a1a;
    width: 40px;
    height: 40px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#send-btn:hover {
    background: #26c6da;
}

.input-footer {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: #888;
    margin-top: 10px;
    padding: 0 10px;
}

footer {
    text-align: center;
    padding: 20px;
    margin-top: 40px;
    border-top: 1px solid #333;
    color: #888;
}

.footer-links a {
    color: #888;
    text-decoration: none;
    margin: 0 10px;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #4dd0e1;
}

/* Modal Styles */
.modal {
    display: none; 
    position: fixed; 
    z-index: 1000; 
    left: 0;
    top: 0;
    width: 100%; 
    height: 100%; 
    overflow: auto; 
    background-color: rgba(0,0,0,0.6); 
}

.modal-content {
    background-color: #2a2a2a;
    margin: 10% auto; 
    padding: 40px;
    border: 1px solid #333;
    width: 90%;
    max-width: 550px;
    border-radius: 15px;
    text-align: center;
    position: relative;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

.modal-content h2 {
    font-size: 32px;
    color: #fff;
    margin-bottom: 10px;
}

.modal-content > p {
    font-size: 16px;
    color: #bdbdbd;
    margin-bottom: 30px;
}

.close-btn {
    color: #aaa;
    position: absolute;
    top: 15px;
    right: 25px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-btn:hover,
.close-btn:focus {
    color: #fff;
}

.developer-info-box {
    border: 1px solid #444;
    border-radius: 10px;
    padding: 25px;
    margin-top: 20px;
    background-color: #333;
}

.developer-info h3 {
    font-size: 22px;
    color: #e0e0e0;
    margin-bottom: 20px;
    text-align: left;
}

.developer-info p {
    font-size: 16px;
    color: #bdbdbd;
    text-align: left;
    margin: 15px 0;
}

.developer-info p i {
    margin-right: 15px;
    color: #4dd0e1;
    width: 20px;
    text-align: center;
}

.developer-info h4 {
    font-size: 18px;
    color: #bdbdbd;
    margin-top: 30px;
    font-weight: 500;
}

.developer-info img {
    width: 180px;
    height: 180px;
    margin-top: 15px;
    border: 4px solid #4dd0e1;
    border-radius: 12px;
    padding: 5px;
    background-color: #fff;
}


#preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #1a1a1a;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    opacity: 1;
    transition: opacity 0.8s ease-in-out;
}

.loader-text {
    font-size: 72px;
    font-weight: bold;
    color: #4dd0e1;
    font-family: 'Roboto', sans-serif;
    text-align: center;
    white-space: nowrap; /* 防止文字换行 */
}

.loader-s {
    opacity: 0;
    animation: fadeInS 1s forwards; /* S 字母淡入 */
}

.loader-rest {
    display: inline-block;
    max-width: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-width 1.5s ease-out, opacity 1s ease-out; /* 展开动画 */
    vertical-align: bottom; /* 确保与S对齐 */
}

/* S 淡入动画 */
@keyframes fadeInS {
    to {
        opacity: 1;
    }
}