:root {
    --primary-blue: #007AFF;
    --hover-blue: rgba(0,122,255,0.1);
    --dark-blue: #0062cc;
    --light-bg: #f0f5ff;
    --card-bg: #ffffff;
    --text-dark: #1D2129;
    --text-light: #6c757d;
    --success: #28a745;
    --shadow: 0 10px 30px rgba(0, 122, 255, 0.15);
    --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, var(--light-bg) 0%, #e6f0ff 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    overscroll-behavior: contain;
    color: var(--text-dark);
    line-height: 1.6;
}

/* 头部样式 */
.header {
    width: 100%;
    max-width: 850px;
    text-align: center;
    margin-bottom: 2rem;
    padding: 0 15px;
}

.logo-container {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 15px;
}

.logo {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--dark-blue) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 28px;
    margin-right: 15px;
    box-shadow: var(--shadow);
}

.title-container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

h1 {
    font-size: 2.4rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--dark-blue) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 0.5rem;
    letter-spacing: -0.5px;
    position: relative;
    display: inline-block;
}

.subtitle {
    color: var(--text-light);
    font-size: 1.1rem;
    font-weight: 400;
    max-width: 500px;
}

/* 容器样式 */
.container {
    max-width: 850px;
    width: 100%;
    padding: 25px;
    background: var(--card-bg);
    border-radius: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

/* 公告样式 */
.announcement {
    background: linear-gradient(135deg, #007AFF 0%, #0062cc 100%);
    color: white;
    padding: 16px 25px;
    border-radius: 16px;
    margin-bottom: 25px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 122, 255, 0.3);
    transition: var(--transition);
}

.announcement::before {
    content: "";
    position: absolute;
    top: -10px;
    right: -10px;
    width: 30px;
    height: 30px;
    background: white;
    border-radius: 50%;
    opacity: 0.1;
}

.announcement::after {
    content: "";
    position: absolute;
    bottom: -20px;
    left: -20px;
    width: 80px;
    height: 80px;
    background: white;
    border-radius: 50%;
    opacity: 0.05;
}

.announcement h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
}

.announcement h3 i {
    margin-right: 10px;
    font-size: 1.4rem;
}

.announcement p {
    font-size: 0.95rem;
    opacity: 0.9;
    margin-bottom: 0;
}

.close-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    position: absolute;
    top: 15px;
    right: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: rotate(90deg);
}

/* 按钮网格样式 */
.button-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.nav-button {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--dark-blue) 100%);
    color: white;
    padding: 20px 25px;
    border-radius: 16px;
    border: none;
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 500;
    transition: var(--transition);
    user-select: none;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    box-shadow: 0 8px 20px rgba(0, 122, 255, 0.25);
}

.nav-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.15);
    opacity: 0;
    transition: opacity 0.3s;
}

.nav-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(0, 122, 255, 0.35);
}

.nav-button:active {
    transform: translateY(0) scale(0.98);
    box-shadow: 0 5px 15px rgba(0, 122, 255, 0.3);
}

.nav-button:hover::before {
    opacity: 1;
}

.button-icon {
    font-size: 1.8rem;
    margin-right: 15px;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.button-text {
    flex: 1;
}

.button-arrow {
    font-size: 1.2rem;
    opacity: 0.7;
}

/* 页脚样式 */
.footer {
    max-width: 850px;
    width: 100%;
    text-align: center;
    padding: 20px;
    color: var(--text-light);
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 15px;
}

.footer-link {
    color: var(--primary-blue);
    text-decoration: none;
    transition: var(--transition);
}

.footer-link:hover {
    color: var(--dark-blue);
    text-decoration: underline;
}

.copyright {
    margin-top: 10px;
    font-size: 0.85rem;
}

/* 状态指示器 */
.status-indicator {
    display: inline-flex;
    align-items: center;
    font-size: 0.9rem;
    padding: 4px 12px;
    border-radius: 50px;
    background: rgba(40, 167, 69, 0.15);
    color: var(--success);
    margin-top: 10px;
}

.status-dot {
    width: 8px;
    height: 8px;
    background: var(--success);
    border-radius: 50%;
    margin-right: 8px;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { opacity: 0.5; }
    50% { opacity: 1; }
    100% { opacity: 0.5; }
}

/* 响应式设计 */
@media (max-width: 700px) {
    .button-grid {
        grid-template-columns: 1fr;
    }
    
    .header {
        padding: 0 10px;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .logo {
        width: 60px;
        height: 60px;
        font-size: 24px;
    }
    
    .nav-button {
        padding: 18px 20px;
    }
    
    .container {
        padding: 20px 15px;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.8rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .nav-button {
        font-size: 1rem;
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
    background: rgba(0,0,0,0.05);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-blue);
    border-radius: 4px;
}