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

body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
    padding: 20px;
    width: 90%;
    max-width: 500px;
}

.advertisement {
    margin-bottom: 20px;
    padding: 15px;
    background-color: #f5f5f5;
    border-radius: 8px;
}

.advertisement h3 {
    color: #333;
    margin-bottom: 10px;
    font-size: 16px;
}

.ad-content img {
    width: 100%;
    height: auto;
    border-radius: 5px;
}

.announcement {
    margin-bottom: 20px;
    padding: 15px;
    background-color: #e8f5e8;
    border-left: 4px solid #4caf50;
    border-radius: 8px;
}

.announcement h3 {
    color: #2e7d32;
    margin-bottom: 10px;
    font-size: 16px;
}

.announcement-content p {
    color: #333;
    line-height: 1.5;
}

.auth-section {
    text-align: center;
    margin-bottom: 20px;
}

.auth-section h1 {
    color: #333;
    margin-bottom: 15px;
    font-size: 24px;
}

.auth-section p {
    color: #666;
    margin-bottom: 25px;
    font-size: 16px;
}

.auth-btn {
    background-color: #1aad19;
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 18px;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(26, 173, 25, 0.3);
}

.auth-btn:hover {
    background-color: #179115;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(26, 173, 25, 0.4);
}

.footer {
    text-align: center;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #eee;
}

.footer p {
    color: #999;
    font-size: 14px;
}

/* 模态框样式 */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background-color: white;
    margin: 15% auto;
    padding: 0;
    border-radius: 8px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    animation: slideIn 0.3s ease;
}

.modal-header {
    padding: 15px 20px;
    background-color: #f8fafc;
    border-bottom: 1px solid #e2e8f0;
    border-radius: 8px 8px 0 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    color: #333;
    margin: 0;
    font-size: 18px;
}

.close-btn {
    color: #64748b;
    font-size: 24px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}

.close-btn:hover {
    color: #334155;
}

.modal-body {
    padding: 20px;
    color: #333;
    line-height: 1.6;
}

.modal-body p {
    margin: 0;
}

/* 公告点击效果 */
.announcement {
    cursor: pointer;
    transition: all 0.3s ease;
}

.announcement:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transform: translateY(-1px);
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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