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

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: linear-gradient(45deg, #1a2a6c, #b21f1f, #fdbb2d);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

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

.container {
    background: rgba(255, 255, 255, 0.95);
    padding: 3rem;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    text-align: center;
    max-width: 600px;
    width: 100%;
    backdrop-filter: blur(10px);
    transform: translateY(0);
    transition: transform 0.3s ease;
}

.container:hover {
    transform: translateY(-5px);
}

h1 {
    color: #2c3e50;
    margin-bottom: 2.5rem;
    font-size: 2.5rem;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
    position: relative;
    padding-bottom: 15px;
}

h1::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, #1877f2, #00b900);
    border-radius: 2px;
}

.button-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    padding: 1rem;
}

.nav-button {
    padding: 1.2rem 2.5rem;
    border: none;
    border-radius: 12px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    color: white;
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    letter-spacing: 1px;
    display: flex;
    align-items: center;
    min-height: 60px;
    justify-content: flex-start;
}

.nav-button i {
    font-size: 1.4rem;
    transition: transform 0.3s ease;
    margin-right: 0.5rem;
    margin-left: 0;
    flex-shrink: 0;
}

.nav-button span {
    flex: 1;
    text-align: center;
    font-weight: 700;
    margin-right: 1.4rem; /* 预留空间防止文字被icon挤压 */
}

.nav-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        120deg,
        transparent,
        rgba(255, 255, 255, 0.2),
        transparent
    );
    transition: 0.5s;
}

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

.nav-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.nav-button:active {
    transform: translateY(-1px);
}

.facebook {
    background: linear-gradient(45deg, #1877f2, #0d6efd);
    box-shadow: 0 4px 15px rgba(24, 119, 242, 0.3);
}

.line {
    background: linear-gradient(45deg, #00b900, #00a800);
    box-shadow: 0 4px 15px rgba(0, 185, 0, 0.3);
}

@media (max-width: 480px) {
    .container {
        padding: 2rem;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .nav-button {
        padding: 1rem 2rem;
        font-size: 1.1rem;
    }
}

/* 添加按钮点击波纹效果 */
.nav-button::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 5px;
    height: 5px;
    background: rgba(255, 255, 255, 0.5);
    opacity: 0;
    border-radius: 100%;
    transform: scale(1, 1) translate(-50%);
    transform-origin: 50% 50%;
}

.nav-button:focus:not(:active)::after {
    animation: ripple 1s ease-out;
}

@keyframes ripple {
    0% {
        transform: scale(0, 0);
        opacity: 0.5;
    }
    100% {
        transform: scale(20, 20);
        opacity: 0;
    }
}