/* ============================================================
   易学天地 - 全局核心样式（稳定版）
   色彩体系：暖灰背景 · 深色卡片 · 鎏金点缀
   视频方案：21:9 比例 · object-fit: contain · 自适应
   ============================================================ */

/* ===== CSS 变量（统一色彩） ===== */
:root {
    /* 背景色系 */
    --color-bg: #f0eee8;          /* 页面主背景：暖灰 */
    --color-bg-card: #2a2824;     /* 卡片背景：深灰 */
    --color-bg-card-hover: #3a322c;
    --color-bg-dropdown: #1e1a16;
    --color-bg-footer: #14100c;

    /* 边框色系 */
    --color-border: #4a3f38;
    --color-border-light: #4a4a6e;
    --color-gold-border: rgba(201, 168, 76, 0.25);

    /* 文字色系（适配浅色背景） */
    --color-h1: #b8942e;          /* 板块大标题：金色 */
    --color-h2: #2a2a3a;          /* 卡片标题：深色 */
    --color-h3: #f0f0f8;          /* 列表标题：深灰 */
    --color-body: #e8e8f0;        /* 正文：深灰 */
    --color-muted: #c0c0d0;       /* 辅助文字：中灰 */

    /* 金色系 */
    --color-gold: #c9a84c;
    --color-gold-dark: #a88830;
    --color-gold-light: #e8c84c;
    --color-gold-glow: rgba(201, 168, 76, 0.12);

    /* 朱砂红（点缀） */
    --color-red: #8b1a1a;
    --color-red-light: #b02020;
    --color-red-glow: rgba(139, 26, 26, 0.12);
}

/* ===== 基础重置 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    /* 微信浏览器强制字体大小 */
    -webkit-text-size-adjust: 100% !important;
    text-size-adjust: 100% !important;
    font-size: 16px;
    font-family: 'SimHei', 'Microsoft YaHei', 'PingFang SC', sans-serif;
    background: var(--color-bg);
    color: var(--color-body);
    min-height: 100vh;
    line-height: 1.8;
    padding-top: 0;
    margin: 0;
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }

/* ===== 滚动条 ===== */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--color-bg); }
::-webkit-scrollbar-thumb { background: var(--color-gold-dark); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--color-gold); }

/* ===== 容器 ===== */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

/* ============================================================
   顶部导航
   ============================================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(20, 20, 30, 0.96);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-gold-border);
    padding: 0 30px;
    height: 64px;
    display: flex;
    align-items: center;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

/* Logo */
.header .logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    gap: 12px;
    text-decoration: none;
    font-size: 0;
}
.header .logo img { height: 38px; width: auto; vertical-align: middle; }
.header .logo span {
    font-size: 26px;
    font-weight: 900;
    color: var(--color-gold);
    font-family: 'SimHei', 'Microsoft YaHei', 'PingFang SC', sans-serif;
    letter-spacing: 3px;
}

/* 导航菜单 */
.nav {
    display: flex;
    align-items: center;
    gap: 2px;
    flex-wrap: wrap;
    flex: 1;
    justify-content: center;
}
.nav-dropdown { position: relative; display: inline-block; }

.nav-dropdown .nav-link,
.nav > a.nav-link {
    cursor: pointer;
    padding: 8px 16px;
    display: inline-block;
    color: var(--color-body);
    text-decoration: none;
    font-size: 15px;
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    transition: all 0.3s ease;
    border-radius: 6px;
    font-weight: 500;
    white-space: nowrap;
}
.nav-dropdown .nav-link:hover,
.nav > a.nav-link:hover {
    color: var(--color-gold);
    background: var(--color-gold-glow);
}

/* 下拉菜单 */
.dropdown-menu {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    min-width: 150px;
    background: var(--color-bg-dropdown);
    border: 1px solid var(--color-gold-border);
    border-radius: 10px;
    padding: 6px 0;
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.6);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}
.nav-dropdown:hover .dropdown-menu {
    display: block;
    opacity: 1;
    visibility: visible;
}
.dropdown-menu::before {
    content: '';
    position: absolute;
    top: -6px;
    left: 50%;
    transform: translateX(-50%) rotate(45deg);
    width: 12px;
    height: 12px;
    background: var(--color-bg-dropdown);
    border-top: 1px solid var(--color-gold-border);
    border-left: 1px solid var(--color-gold-border);
}
.dropdown-menu a {
    display: block;
    padding: 10px 22px;
    color: var(--color-body);
    text-decoration: none;
    font-size: 14px;
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    transition: all 0.25s ease;
    border-left: 3px solid transparent;
    white-space: nowrap;
}
.dropdown-menu a:hover {
    background: var(--color-gold-glow);
    color: var(--color-gold);
    border-left-color: var(--color-gold);
}

/* 认证按钮 */
.auth {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}
.auth a {
    color: var(--color-body);
    font-size: 14px;
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    transition: color 0.3s;
    padding: 6px 12px;
    border-radius: 6px;
}
.auth a:hover { color: var(--color-gold); }
.auth .btn-register {
    background: linear-gradient(135deg, var(--color-gold), var(--color-gold-dark));
    color: #0c0c14;
    font-weight: 700;
    padding: 6px 20px;
    border-radius: 20px;
    transition: all 0.3s;
}
.auth .btn-register:hover {
    background: linear-gradient(135deg, var(--color-gold-light), var(--color-gold));
    color: #0c0c14;
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(201, 168, 76, 0.3);
}

/* ============================================================
   视频Banner - 稳定自适应方案（21:9）
   ============================================================ */
.banner-video {
    position: relative;
    width: 100%;
    max-width: 100vw;
    overflow: hidden;
    background: var(--color-bg);
    aspect-ratio: 21 / 9;
    margin: 0 auto;
    padding: 0; margin-top: 61px;
    line-height: 0;
    display: block;
}
.banner-video-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    background: var(--color-bg);
    z-index: 1;
    display: block;
}

/* ============================================================
   内容区块
   ============================================================ */
.section { padding: 60px 0; }
.section-sm { padding: 40px 0; }
.section-lg { padding: 80px 0; }

/* ============================================================
   标题体系
   ============================================================ */
.section-title {
    font-size: 34px;
    font-weight: 700;
    color: var(--color-h1);
    
    
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
    text-align: center;
    letter-spacing: 6px;
    margin-bottom: 8px;
}
.section-title .highlight { color: #e8e8f0; }

.section-subtitle {
    color: #333333 !important;
    text-align: center;
    color: var(--color-muted);
    font-size: 18px;
    letter-spacing: 4px;
    margin-bottom: 40px;
    font-weight: 300;
}

.section-divider {
    width: 80px;
    height: 3px;
    background: linear-gradient(90deg, var(--color-red), var(--color-gold), var(--color-red));
    margin: 12px auto 32px;
    border-radius: 2px;
    opacity: 0.6;
}

/* ============================================================
   卡片
   ============================================================ */
.card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 28px;
    transition: all 0.3s ease;
}
.card:hover {
    border-color: var(--color-gold-border);
    background: var(--color-bg-card-hover);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

/* ============================================================
   按钮
   ============================================================ */
.btn-primary {
    display: inline-block;
    padding: 12px 36px;
    background: linear-gradient(135deg, var(--color-gold), var(--color-gold-dark));
    color: #0c0c14;
    font-weight: 700;
    font-size: 18px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'Microsoft YaHei', sans-serif;
    letter-spacing: 2px;
}
.btn-primary:hover {
    background: linear-gradient(135deg, var(--color-gold-light), var(--color-gold));
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(201, 168, 76, 0.3);
}

.btn-secondary {
    display: inline-block;
    padding: 12px 36px;
    background: var(--color-bg);
    color: var(--color-gold);
    font-weight: 600;
    font-size: 18px;
    border: 1.5px solid var(--color-gold);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'Microsoft YaHei', sans-serif;
    letter-spacing: 2px;
}
.btn-secondary:hover {
    background: var(--color-gold-glow);
    transform: translateY(-2px);
}

/* ============================================================
   工具卡片网格
   ============================================================ */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 24px;
    margin-top: 20px;
}
.tool-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 32px 20px;
    text-align: center;
    transition: all 0.4s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}
.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-red), var(--color-gold));
    opacity: 0;
    transition: opacity 0.4s ease;
}
.tool-card:hover {
    border-color: var(--color-gold-border);
    background: var(--color-bg-card-hover);
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.35);
}
.tool-card:hover::before { opacity: 1; }

.tool-card .tool-icon { font-size: 40px; margin-bottom: 14px; display: block; }
.tool-card h3 {
    color: var(--color-h3);
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
}
.tool-card p {
    color: var(--color-muted);
    font-size: 13px;
    margin-bottom: 14px;
    line-height: 1.6;
}
.tool-card .tool-status {
    display: inline-block;
    padding: 2px 14px;
    border-radius: 12px;
    font-size: 11px;
    font-weight: 500;
}
.tool-card .tool-status.available {
    background: var(--color-gold-glow);
    color: var(--color-gold);
}
.tool-card .tool-status.coming {
    background: rgba(255, 255, 255, 0.04);
    color: var(--color-muted);
}

/* ============================================================
   特色网格
   ============================================================ */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
    margin-top: 20px;
}
.feature-item {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 28px 20px;
    text-align: center;
    transition: all 0.3s ease;
}
.feature-item:hover {
    border-color: var(--color-gold-border);
    background: var(--color-bg-card-hover);
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}
.feature-item .feature-icon { font-size: 36px; margin-bottom: 12px; display: block; }
.feature-item h4 {
    color: var(--color-h3);
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 6px;
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
}
.feature-item p {
    color: var(--color-muted);
    font-size: 13px;
    line-height: 1.6;
}

/* ============================================================
   页脚
   ============================================================ */
.footer {
    background: var(--color-bg-footer);
    border-top: 1px solid var(--color-border);
    padding: 40px 0 20px;
    margin-top: 0;
}
.footer .footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--color-border);
}
.footer .footer-brand .footer-logo {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-gold);
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
}
.footer .footer-brand p {
    color: var(--color-muted);
    font-size: 13px;
    margin-top: 4px;
}
.footer .footer-links {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}
.footer .footer-links a {
    color: var(--color-muted);
    font-size: 13px;
    transition: color 0.3s;
}
.footer .footer-links a:hover { color: var(--color-gold); }
.footer .footer-bottom {
    text-align: center;
    padding-top: 16px;
}
.footer .footer-bottom p {
    color: var(--color-muted);
    font-size: 12px;
    opacity: 0.7;
}

/* ============================================================
   响应式适配
   ============================================================ */
@media (max-width: 1200px) {
    .container { padding: 0 30px; }
    .header .container { padding: 0 30px; }
}
@media (max-width: 992px) {
    .container { padding: 0 20px; }
    .header .container { padding: 0 20px; }
    .header { padding: 0 20px; }
    .nav-dropdown .nav-link,
    .nav > a.nav-link { font-size: 13px; padding: 6px 10px; }
    .header .logo span { font-size: 22px; }
    .auth a { font-size: 13px; padding: 4px 10px; }
    .section-title { font-size: 28px; letter-spacing: 4px; }
    .section { padding: 40px 0; }
}
@media (max-width: 768px) {
    .banner-video { margin-top: 70px !important; }
    .header {
        height: auto;
        padding: 10px 16px;
    }
    .header .container {
        flex-wrap: wrap;
        gap: 6px;
        padding: 0 16px;
    }
    .nav {
        order: 3;
        width: 100%;
        justify-content: center;
        gap: 2px;
        padding-top: 8px;
        border-top: 1px solid var(--color-gold-border);
    }
    .nav-dropdown .nav-link,
    .nav > a.nav-link { font-size: 12px; padding: 4px 8px; }
    .dropdown-menu {
        position: fixed;
        top: auto;
        left: 10px;
        right: 10px;
        transform: none;
        width: auto;
        min-width: auto;
        border-radius: 8px;
    }
    .dropdown-menu::before { display: none; }
    .auth { gap: 6px; }
    .auth a { font-size: 12px; padding: 4px 10px; }
    .header .logo span { font-size: 18px; letter-spacing: 2px; }
    .section-title { font-size: 22px; letter-spacing: 3px; }
    .section-subtitle { font-size: 14px; letter-spacing: 2px; }
    color: #333333 !important;
    .section { padding: 30px 0; }
    .tool-grid { grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 16px; }
    .features-grid { grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 16px; }
    .footer .footer-content { flex-direction: column; text-align: center; }
}
@media (max-width: 480px) {
    .header { padding: 8px 12px; }
    .header .container { padding: 0 12px; gap: 4px; }
    .nav-dropdown .nav-link,
    .nav > a.nav-link { font-size: 10px; padding: 3px 5px; }
    .auth a { font-size: 10px; padding: 3px 6px; }
    .auth .btn-register { padding: 3px 10px; font-size: 10px; }
    .header .logo span { font-size: 15px; letter-spacing: 1px; }
    .section-title { font-size: 18px; letter-spacing: 2px; }
    .section-subtitle { font-size: 12px; letter-spacing: 1px; }
    color: #333333 !important;
    .section { padding: 24px 0; }
    .tool-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .tool-card { padding: 20px 12px; }
    .tool-card .tool-icon { font-size: 28px; }
    .tool-card h3 { font-size: 14px; }
    .features-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
    .feature-item { padding: 20px 12px; }
    .feature-item .feature-icon { font-size: 28px; }
    .feature-item h4 { font-size: 14px; }
    .btn-primary,
    .btn-secondary { padding: 10px 20px; font-size: 14px; }
}
/* ===== 手机菜单按钮（在 common.css 中统一） ===== */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 6px 4px;
    margin-left: 12px;
}
.mobile-menu-btn span {
    display: block;
    width: 26px;
    height: 3px;
    background: #c9a84c;
    border-radius: 2px;
    transition: 0.3s;
}

.mobile-menu-panel {
    display: none;
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100%;
    background: #1a1a2a;
    z-index: 9999;
    transition: right 0.35s ease;
    box-shadow: -4px 0 30px rgba(0,0,0,0.5);
    overflow-y: auto;
    padding: 0 0 30px 0;
}
.mobile-menu-panel.open {
    right: 0;
    display: block;
}
.mobile-menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 20px;
    border-bottom: 1px solid rgba(201,168,76,0.15);
    background: #0f0f1a;
}
.mobile-menu-header span {
    font-size: 20px;
    font-weight: 700;
    color: #c9a84c;
    font-family: 'SimHei', 'Microsoft YaHei', sans-serif;
}
.mobile-menu-close {
    background: transparent;
    border: none;
    color: #c0c0d0;
    font-size: 22px;
    cursor: pointer;
    padding: 4px 8px;
}
.mobile-menu-list {
    list-style: none;
    padding: 8px 0;
    margin: 0;
}
.mobile-menu-list li a {
    display: block;
    padding: 12px 24px;
    color: #c0c0d0;
    text-decoration: none;
    font-size: 15px;
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    border-left: 3px solid transparent;
    transition: all 0.25s;
}
.mobile-menu-list li a:hover {
    background: rgba(201,168,76,0.08);
    color: #c9a84c;
    border-left-color: #c9a84c;
}
.mobile-menu-divider {
    height: 1px;
    background: rgba(255,255,255,0.06);
    margin: 8px 16px;
}
.mobile-menu-list .mobile-btn-register {
    background: linear-gradient(135deg, #c9a84c, #a88830);
    color: #0c0c14 !important;
    font-weight: 600;
    border-radius: 20px;
    margin: 4px 16px;
    text-align: center;
    border-left: none !important;
}
.mobile-menu-list .mobile-btn-register:hover {
    background: linear-gradient(135deg, #e8c84c, #c9a84c);
    color: #0c0c14 !important;
}

@media (max-width: 768px) {
    .banner-video { margin-top: 70px !important; }
    .mobile-menu-btn { display: flex !important; }
}