/* ============================================================
   NAVBAR - yamachun-nav
   ============================================================ */
   yamachun-nav nav.yamachun-navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5%;
    background: var(--nav-bg);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--border-light);
    z-index: 10000;
    box-sizing: border-box;
    transition: all 0.4s ease;
}

/* Logo 部分 */
.nav-logo-container {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.nav-logo-img {
    height: 32px;
    width: auto;
    filter: var(--logo-filter); /* 在 variables.css 中定义反色 */
    transition: filter 0.5s ease;
}

/* 链接部分 */
.nav-links {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav-item {
    font-family: var(--font-art);
    font-size: 0.85rem;
    color: var(--text-muted);
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    padding: 5px 0;
}

.nav-item:hover, .nav-item.active {
    color: var(--text-main);
}

/* 激活状态的下划线 */
.nav-item::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--accent-color);
    transition: width 0.3s ease;
}

.nav-item:hover::after, .nav-item.active::after {
    width: 100%;
}

/* 模式切换按钮 */
#mode-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    border: 1px solid var(--border-light);
    border-radius: 50%;
    width: 34px;
    height: 34px;
    margin-left: 10px;
    color: var(--text-muted);
    transition: 0.3s;
}

#mode-toggle:hover {
    border-color: var(--accent-color);
    color: var(--text-main);
}

/* ============================================================
   FOOTER - yamachun-footer
   ============================================================ */
.yamachun-footer-container {
    background: var(--primary-bg);
    padding: 80px 5% 40px;
    border-top: 1px solid var(--border-light);
    margin-top: 100px;
    color: var(--text-main);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1.5fr;
    gap: 40px;
    max-width: 1400px;
    margin: 0 auto;
}

.footer-brand .brand-title {
    font-family: var(--font-ui);
    font-weight: 800;
    font-size: 1.4rem;
    line-height: 1.1;
    margin-bottom: 15px;
    text-transform: uppercase;
}

.brand-status {
    font-family: var(--font-mono);
    font-size: 0.65rem;
    color: var(--text-muted);
    letter-spacing: 1px;
}

.footer-column h4 {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--accent-color);
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.footer-column ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-column ul li {
    margin-bottom: 10px;
}

.footer-column ul li a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: 0.3s;
}

.footer-column ul li a:hover {
    color: var(--text-main);
}

.footer-bottom {
    max-width: 1400px;
    margin: 60px auto 0;
    padding-top: 25px;
    border-top: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-muted);
}

.privacy-btn {
    background: none;
    border: 1px solid var(--border-light);
    color: var(--text-muted);
    padding: 4px 12px;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    cursor: pointer;
    transition: 0.3s;
}

.privacy-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}