/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
@supports (--css: variables) {
  :root {
    /* 基础颜色系统 - 便于整体风格切换 */
    /* 主色调 */
    --primary-color: #1e88e5;
    --primary-dark: #0066cc;
    --primary-light: #3594fa;
    
    /* 辅助色 */
    --error-color: #ef5350;
    --warning-color: #ffe08a;
    
    /* 中性色 */
    --text-dark: #333;
    --text-medium: #666;
    --text-light: #999;
    --border-light: #ddd;
    --border-lighter: #eee;
    
    /* 背景色 */
    --bg-light: #f5f5f5;
    --bg-medium: #f8f9fa;
    --bg-white: #fff;
    
    /* 特殊颜色 */
    --burgundy: #800020;
    --marksgreen: #008c8c;
    --tiffany: #81d8d0;
    --deep-blue: #182C61;
    --navy: #2c3e50;
    --link-color: #111e36;
  }
}
body {
    font-family: 'Segoe UI', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
}
h1, h2, h3, h4, h5, h6 {
    color: var(--primary-color);
}
/* 定义通用的a链接没有下划线 */
a {
    color: var(--link-color);
    text-decoration: none;
}
a:visited {
    color: var(--text-light); /*已访问的链接颜色*/
}

.container {
    margin: 0 3% 30px;
    padding: 0;
}
.msgpage {
    margin: 5% 5% ;
    padding: 0;
}
.header {
    margin-bottom: 10px;
    font-size: 1.8em;
    color: var(--text-dark);
    font-weight: 600;
}

.color-incorrect { color: var(--error-color);
    font-weight: 800;
    fill: #ef5350;
}
.color-burgundy { color: var(--burgundy);
}
.color-marksgreen { color: var(--marksgreen);
}
.color-tiffany { color: var(--tiffany);
}

/* Header Styles */
.site-header {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    padding: 10px 5%;
    background-color: var(--bg-light);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    height: auto;
    white-space: nowrap;
}

.header-logo {
    margin-right: auto;
}
.header-logo img {
    height: 50px;
}
.main-nav {
    flex: 1;
    min-width: 0;
}
.header-actions {
    display: flex;
    gap: 15px;
    margin-left: auto;
}
.slogan {
    width: 100%;
    text-align: center;
    font-size: 14px;
    color: var(--text-medium);
    margin-top: 5px;
}

.login-tip {
    display: none;
    position: absolute;
    right: 5%;
    top: 50px;
    background: #fff3cd;
    padding: 8px 15px;
    border-radius: 4px;
    color: #856404;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    z-index: 100;
}

.login-tip::after {
    content: '';
    position: absolute;
    bottom: 100%;
    right: 20px;
    border-width: 5px;
    border-style: solid;
    border-color: transparent transparent #fff3cd transparent;
}

.login-btn, .register-btn {
    height: 40px;
    padding: 5px 20px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 500;
}

.login-btn {
    color: #333;
    border: 1px solid #ddd;
}
.login-btn:hover {
    background-color: var(--primary-color);
    color: white;
}
.register-btn {
    background-color: var(--primary-dark);
    color: white;
}
.register-btn:hover {
    background-color: var(--primary-color);
    color: white;
}

.main-nav ul {
    margin-left:50px;
    display: flex;
    list-style: none;
    gap: 30px 10px;
    justify-content:flex-start;
}

.main-nav a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.main-nav a:hover {
    color: var(--primary-dark);
}


@keyframes underline {
    from {
        transform: scaleX(0);
        opacity: 0;
    }
    to {
        transform: scaleX(1);
        opacity: 1;
    }
}
/* Footer Styles */
.site-footer {
    background-color: var(--navy);
    color: white;
    padding: 50px 5% 30px;
    margin-top: 50px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column {
    padding: 0 15px;
}

.footer-column h3 {
    margin-bottom: 20px;
    font-size: 1.1em;
    position: relative;
    padding-bottom: 10px;
}

.footer-column h3:after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 40px;
    height: 2px;
    background: rgba(255,255,255,0.3);
}

.footer-column p {
    line-height: 1.7;
    color: rgba(255,255,255,0.7);
    font-size: 0.9em;
}

.footer-qrcode img {
    width: 100px;
    height: 100px;
    margin-bottom: 10px;
}

.footer-qrcode a {
    color: #4dabf7;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-qrcode a:hover {
    color: #74c0fc;
    text-decoration: underline;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    font-size: 0.9em;
}

.footer-bottom a {
    color: rgba(255,255,255,0.7);
    margin: 0 10px;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-bottom a:hover {
    color: #fff;
}

/* 移动端适配 */
@media (max-width: 768px) {
    .site-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
        padding: 10px 2%;
    }
    .header-logo img {
        height: 40px;
    }
    .main-nav {
        width: 100%;
        margin-bottom: 10px;
    }
    .main-nav ul {
        display: flex;
        gap: 10px;
        justify-content: space-between;
        flex-wrap: wrap;
    }
    .header-actions {
        width: 100%;
        justify-content: center;
        margin-left: 0;
        margin-top: 10px;
        gap: 8px;
    }

}   


/* SEO Section Styles */
.msg {
    display: flex;
    gap: 0.8rem;
    background: #fff9e6;
    border-radius: 6px;
    padding: 1rem;
    margin: 1.5rem 0;
    border-left: 3px solid var(--warning-color);
}

.msg > span {
    font-weight: 600;
    color: #856404;
    min-width: 80px;
}

.msg p {
    margin: 0;
    flex: 1;
}