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

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    color: white;
    overflow-x: hidden;
}

/* 动态背景 */
.animated-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: linear-gradient(-45deg, #1a1a1a, #2d2d2d, #8b0000, #4a4a4a);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* 遮罩层 */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.3);
    z-index: -1;
}

/* 浮动粒子效果 */
.floating-particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

.particle:nth-child(1) {
    left: 10%;
    animation-delay: 0s;
    animation-duration: 8s;
}

.particle:nth-child(2) {
    left: 20%;
    animation-delay: 2s;
    animation-duration: 10s;
}

.particle:nth-child(3) {
    left: 30%;
    animation-delay: 4s;
    animation-duration: 7s;
}

.particle:nth-child(4) {
    left: 40%;
    animation-delay: 1s;
    animation-duration: 9s;
}

.particle:nth-child(5) {
    left: 50%;
    animation-delay: 3s;
    animation-duration: 6s;
}

.particle:nth-child(6) {
    left: 60%;
    animation-delay: 5s;
    animation-duration: 8s;
}

.particle:nth-child(7) {
    left: 70%;
    animation-delay: 2s;
    animation-duration: 11s;
}

.particle:nth-child(8) {
    left: 80%;
    animation-delay: 4s;
    animation-duration: 7s;
}

.particle:nth-child(9) {
    left: 90%;
    animation-delay: 1s;
    animation-duration: 9s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(100vh) scale(0);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(-100px) scale(1);
        opacity: 0;
    }
}

/* 头部 */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 50px;
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
}

.logo {
    font-size: 28px;
    font-weight: bold;
    color: #fff;
    text-decoration: none;
}

.app-download {
    background: linear-gradient(45deg, #8b0000, #a52a2a);
    color: white;
    padding: 12px 24px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
}

.app-download:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(139, 0, 0, 0.4);
}

/* 主体内容 */
.main-content {
    min-height: calc(100vh - 200px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 50px 20px;
    text-align: center;
}

.site-name {
    font-size: 48px;
    font-weight: bold;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.site-description {
    font-size: 20px;
    margin-bottom: 50px;
    max-width: 800px;
    line-height: 1.6;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
}

.line-selection {
    margin-bottom: 50px;
}

.line-title {
    font-size: 24px;
    margin-bottom: 30px;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
}

.line-buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    justify-content: center;
}

.line-btn {
    background: linear-gradient(45deg, #8b0000, #a52a2a);
    color: white;
    padding: 15px 30px;
    border: none;
    border-radius: 30px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

.line-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(139, 0, 0, 0.4);
}

/* 底部 */
.footer {
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    padding: 30px 50px;
    text-align: center;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-section {
    flex: 1;
    min-width: 250px;
}

.footer-section h3 {
    margin-bottom: 15px;
    color: #8b0000;
}

.footer-section p, .footer-section a {
    color: #ccc;
    text-decoration: none;
    line-height: 1.6;
}

.footer-section a:hover {
    color: #8b0000;
}

.social-links {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 10px;
}

.social-links a {
    color: #8b0000;
    font-size: 20px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header {
        padding: 15px 20px;
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
    }

    .logo {
        font-size: 24px;
    }

    .app-download {
        padding: 10px 20px;
        font-size: 14px;
    }

    .site-name {
        font-size: 36px;
    }

    .site-description {
        font-size: 18px;
    }

    .line-buttons {
        flex-direction: column;
        align-items: center;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

/* 超小屏幕适配 */
@media (max-width: 480px) {
    .header {
        padding: 10px 15px;
    }

    .logo {
        font-size: 20px;
    }

    .app-download {
        padding: 8px 16px;
        font-size: 12px;
    }
}