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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(-45deg, #ee7752, #e73c7e, #23a6d5, #23d5ab);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #333;
    position: relative;
    overflow: hidden;
}

/* 动态背景动画 */
@keyframes gradientBG {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* 浮动粒子效果 */
.particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    pointer-events: none;
}

.particle {
    position: absolute;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

.particle:nth-child(1) {
    width: 60px;
    height: 60px;
    top: 20%;
    left: 10%;
    animation-delay: 0s;
}

.particle:nth-child(2) {
    width: 40px;
    height: 40px;
    top: 60%;
    right: 15%;
    animation-delay: 2s;
}

.particle:nth-child(3) {
    width: 30px;
    height: 30px;
    bottom: 30%;
    left: 20%;
    animation-delay: 4s;
}

.particle:nth-child(4) {
    width: 50px;
    height: 50px;
    top: 40%;
    right: 25%;
    animation-delay: 1s;
}

.particle:nth-child(5) {
    width: 35px;
    height: 35px;
    bottom: 20%;
    right: 10%;
    animation-delay: 3s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
        opacity: 0.3;
    }
    50% {
        transform: translateY(-20px) rotate(180deg);
        opacity: 0.8;
    }
}

.container {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    padding: 3rem;
    text-align: center;
    max-width: 480px;
    width: 90%;
    animation: fadeIn 0.6s ease-out;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    margin: 0 auto 2rem;
    display: block;
    border: 3px solid rgba(255, 255, 255, 0.8);
    transition: transform 0.3s ease;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}

.avatar:hover {
    transform: scale(1.05);
}

.logo {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #212529;
}

.subtitle {
    font-size: 1rem;
    color: #6c757d;
    margin-bottom: 2.5rem;
    font-weight: 400;
}

.nav-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.nav-button {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    display: block;
    position: relative;
    overflow: hidden;
}

.nav-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
}

.nav-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

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

.nav-button:active {
    transform: translateY(0);
}

.description {
    font-size: 0.875rem;
    color: #6c757d;
    line-height: 1.5;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 2rem 1.5rem;
        margin: 1rem;
    }
    
    .logo {
        font-size: 1.5rem;
    }
    
    .nav-button {
        padding: 0.875rem 1.5rem;
    }
    
    .particle {
        display: none;
    }
}