:root {
    /* 主色：青金石蓝 */
    --c-primary: #1E3A5F;
    --c-primary-light: #2C5282;
    --c-primary-dark: #0F2440;

    /* 辅色：沙漠金 */
    --c-gold: #C9A063;
    --c-gold-light: #E0C48A;
    --c-gold-dark: #A67C3D;

    /* 点缀：朱砂红 */
    --c-red: #B23A2E;
    --c-red-light: #D45A4A;

    /* 背景：宣纸白 */
    --c-bg: #F7F3EC;
    --c-bg-card: #FFFFFF;
    --c-bg-soft: #FBF8F3;

    /* 文字 */
    --c-text: #1E2F4E;
    --c-text-sub: #5D6F88;
    --c-text-light: #8A9BB0;

    /* 边框 */
    --c-border: #E8E0D4;
    --c-border-light: #F0EBE2;

    /* 字体 */
    --font-title: '方正清刻本悦宋', 'STSong', 'SimSun', serif;
    --font-body: '思源宋体', 'Noto Serif SC', 'STSong', 'SimSun', serif;
    --font-num: 'Georgia', 'Times New Roman', serif;

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;

    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(30, 58, 95, 0.06);
    --shadow-md: 0 8px 24px rgba(30, 58, 95, 0.08);
    --shadow-lg: 0 20px 40px rgba(30, 58, 95, 0.10);
}

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

body {
    font-family: var(--font-body);
    background: var(--c-bg);
    color: var(--c-text);
    line-height: 1.6;
    /* 宣纸纹理（CSS 渐变模拟） */
    background-image:
        radial-gradient(circle at 20% 30%, rgba(201, 160, 99, 0.04) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(30, 58, 95, 0.03) 0%, transparent 50%);
}

/* 标题 */
h1,
h2,
h3,
h4 {
    font-family: var(--font-title);
    color: var(--c-primary);
    font-weight: 700;
    letter-spacing: 1px;
}

/* 导航栏 */
.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px 12px 32px;
    background: var(--c-bg-card);
    border-bottom: 2px solid var(--c-gold);
    flex-wrap: wrap;
    gap: 8px;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 0;
    font-family: var(--font-title);
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--c-primary);
    text-decoration: none;
    white-space: nowrap;
    flex-shrink: 0;
    min-width: 140px;
    justify-content: flex-start;
}

.navbar-brand span {
    background: linear-gradient(135deg, var(--c-gold-dark), var(--c-gold));
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-links {
    display: flex;
    gap: 3px;
    flex-wrap: wrap;
    align-items: center;
}

.nav-links a {
    padding: 6px 11px;
    border-radius: 40px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--c-text-sub);
    text-decoration: none;
    transition: all 0.25s;
    cursor: pointer;
    border: 1px solid transparent;
    white-space: nowrap;
}

.nav-links a:hover {
    background: var(--c-bg-soft);
    color: var(--c-primary);
    border-color: var(--c-gold-light);
}

.nav-links a.active {
    background: var(--c-primary);
    color: #fff;
    border-color: var(--c-primary);
}

/* 导航分组分隔符 */
.nav-divider {
    color: var(--c-border);
    font-size: 0.75rem;
    display: flex;
    align-items: center;
    padding: 0 1px;
    user-select: none;
}

/* 高亮入口：答题闯关 / 丝路剧场 */
.nav-links a.nav-highlight {
    background: linear-gradient(135deg, rgba(201, 160, 99, 0.15), rgba(201, 160, 99, 0.05));
    border: 1px solid rgba(201, 160, 99, 0.4);
    color: var(--c-gold-dark);
    font-weight: 700;
    padding: 6px 9px;
    font-size: 0.76rem;
}

.nav-links a.nav-highlight:hover {
    background: linear-gradient(135deg, var(--c-gold), var(--c-gold-dark));
    color: #fff;
    border-color: var(--c-gold);
}

.nav-links a.nav-highlight.active {
    background: linear-gradient(135deg, var(--c-gold), var(--c-gold-dark));
    color: #fff;
    border-color: var(--c-gold);
}

/* 用户栏 */
.user-bar {
    display: flex;
    align-items: center;
    gap: 10px;
    justify-content: flex-end;
    min-width: 140px;
}

.user-chip {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px 6px 6px;
    border-radius: 40px;
    background: var(--c-bg-soft);
    border: 1px solid var(--c-border);
    cursor: pointer;
    transition: all 0.25s;
    text-decoration: none;
}

.user-chip:hover {
    border-color: var(--c-gold);
    background: #fff;
}

.user-chip .avatar {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--c-gold), var(--c-gold-dark));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.95rem;
    color: #fff;
}

.user-chip .name {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--c-primary);
}

/* 卡片 */
.card {
    background: var(--c-bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--c-border-light);
    box-shadow: var(--shadow-sm);
    padding: 24px;
    transition: all 0.3s ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-4px);
    border-color: var(--c-gold-light);
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 48px;
    font-family: var(--font-body);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.25s;
    text-decoration: none;
}

.btn-primary {
    background: var(--c-primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--c-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-gold {
    background: linear-gradient(135deg, var(--c-gold), var(--c-gold-dark));
    color: #fff;
}

.btn-gold:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-ghost {
    background: var(--c-bg-soft);
    color: var(--c-primary);
    border: 1px solid var(--c-border);
}

.btn-ghost:hover {
    background: var(--c-bg);
    border-color: var(--c-gold);
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 24px 32px;
    font-size: 0.8rem;
    color: var(--c-text-light);
    border-top: 1px solid var(--c-border-light);
    background: var(--c-bg-card);
    font-family: var(--font-body);
}

/* 动效 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes flowLine {
    0% {
        stroke-dashoffset: 1000;
    }

    100% {
        stroke-dashoffset: 0;
    }
}

@keyframes pulse {

    0%,
    100% {
        transform: scale(1);
        opacity: 1;
    }

    50% {
        transform: scale(1.05);
        opacity: 0.85;
    }
}

.animate-fade-up {
    animation: fadeInUp 0.8s ease both;
}

.animate-fade {
    animation: fadeIn 1s ease both;
}

.delay-1 {
    animation-delay: 0.1s;
}

.delay-2 {
    animation-delay: 0.2s;
}

.delay-3 {
    animation-delay: 0.3s;
}

.delay-4 {
    animation-delay: 0.4s;
}

.delay-5 {
    animation-delay: 0.5s;
}

/* 滚动条 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--c-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--c-border);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--c-gold);
}

/* 响应式 */
@media (max-width: 1250px) {
    .nav-divider {
        display: none;
    }
}

@media (max-width: 1100px) {
    .nav-links a.nav-highlight {
        padding: 5px 8px;
        font-size: 0.72rem;
    }
}

@media (max-width: 768px) {
    .navbar {
        padding: 10px 12px;
    }

    .navbar-brand {
        font-size: 1rem;
    }

    .nav-links a {
        padding: 5px 8px;
        font-size: 0.7rem;
    }

    .nav-links a.nav-highlight {
        padding: 4px 7px;
        font-size: 0.68rem;
    }

    .card {
        padding: 16px;
    }

    .btn {
        padding: 10px 20px;
        font-size: 0.85rem;
    }
}

.logout-btn {
    padding: 6px 14px;
    border-radius: 40px;
    border: 1px solid var(--c-border);
    background: var(--c-bg-soft);
    color: var(--c-text-sub);
    font-size: 0.8rem;
    font-family: var(--font-body);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.logout-btn:hover {
    border-color: var(--c-red);
    color: var(--c-red);
    background: #FFF5F5;
}

body {
    background-color: var(--c-bg);
    background-image:
        /* 宣纸纹理 */
        repeating-linear-gradient(45deg,
            transparent,
            transparent 2px,
            rgba(201, 160, 99, 0.015) 2px,
            rgba(201, 160, 99, 0.015) 4px),
        /* 主光晕 */
        radial-gradient(ellipse at 20% 30%, rgba(201, 160, 99, 0.06) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 70%, rgba(30, 58, 95, 0.05) 0%, transparent 50%);
}

h1,
h2 {
    position: relative;
}

h1::after,
.section-header h2::after {
    content: "";
    display: block;
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--c-gold), transparent);
    margin-top: 10px;
    border-radius: 3px;
}

.card,
.chart-card,
.timeline-section,
.page-header,
.module-item,
.entry-card {
    position: relative;
}

.card::before,
.chart-card::before {
    content: "";
    position: absolute;
    top: 12px;
    left: 12px;
    right: 12px;
    bottom: 12px;
    border: 1px solid rgba(201, 160, 99, 0.1);
    border-radius: calc(var(--radius-lg) - 8px);
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s;
}

.card:hover::before,
.chart-card:hover::before {
    opacity: 1;
}

.btn-gold {
    position: relative;
    overflow: hidden;
}

.btn-gold::after {
    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;
}

.btn-gold:hover::after {
    left: 100%;
}

.chart-card {
    animation: chartGrow 0.8s ease both;
}

@keyframes chartGrow {
    from {
        opacity: 0;
        transform: scale(0.96);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

body {
    animation: pageFadeIn 0.6s ease;
}

@keyframes pageFadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.nav-links a.active {
    position: relative;
}

.nav-links a.active::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 2px;
    background: var(--c-gold);
    border-radius: 2px;
}

.stat-num,
.header-stat .num {
    font-family: var(--font-num);
    text-shadow: 0 1px 2px rgba(201, 160, 99, 0.2);
}

.timeline-section::before,
.timeline-section::after {
    content: "❖";
    position: absolute;
    font-size: 0.8rem;
    color: var(--c-gold);
    opacity: 0.4;
}

.timeline-section::before {
    top: 12px;
    left: 16px;
}

.timeline-section::after {
    bottom: 12px;
    right: 16px;
}

.chart-conclusion {
    margin: 24px 0;
    padding: 24px 28px;
    background: var(--c-bg-card);
    border: 1px solid var(--c-border-light);
    border-left: 4px solid var(--c-gold);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    font-size: 0.95rem;
    color: var(--c-text);
    line-height: 1.8;
}

.chart-conclusion::before {
    content: "💡 ";
    font-size: 1rem;
}

.chart-conclusion strong {
    color: var(--c-primary);
    font-weight: 700;
}