/**
 * header-kyroc.css — Kyroc 主站页眉导航单一真源（由 index-nav.css 拆分，2026-08-06）
 * 适用：index.html / kyroc/buy.html / kyroc/contact.html
 * 范围：.nav 顶部导航、.nav-links、.nav-dropdown 下拉、.nav-cta、.mobile-menu-btn
 * 不含弹出菜单（#menu-overlay/#popup-menu，已在 popup-menu.css）；不含 #hamburger-menu（同 popup-menu.css）
 */

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-nav-header);
    padding: 0 var(--space-10);
    margin: 0;
    height: var(--header-height);
    width: auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    text-align: left;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.06);
    transition: all var(--dur) var(--ease);
}

.header-menu {
    width: 100%;
    display: block;
}

.header-menu-2 {
    height: var(--header-height);
    width: 100%;
    background-color: var(--surface-page);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-logo {
    margin-left: var(--space-3);
    display: flex;
    align-items: center;
}

.header-logo img {
    width: 36px;
    height: 36px;
}

.logo-subtitle {
    margin-left: var(--space-3);
    margin-top: var(--space-2);
    font-size: 12px;
    color: var(--text-secondary);
}


.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    position: relative;
    min-width: 100px;
}

.nav-logo-img {
    width: 36px;
    height: 36px;
    opacity: 1;
    transform: translateX(0) scale(1);
    transition: opacity 0.35s ease, transform 0.35s ease;
    flex-shrink: 0;
}

.nav-logo-text {
    font-size: var(--font-size-logo);
    font-weight: 700;
    color: var(--color-text);
    letter-spacing: -0.5px;
    opacity: 0;
    transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%) translateX(20px);
    pointer-events: none;
    white-space: nowrap;
}

/* 滚动后：显示图标，隐藏文字 */
.nav.scrolled .nav-logo-img {
    opacity: 1;
    transform: translateX(0) scale(1);
}

.nav.scrolled .nav-logo-text {
    opacity: 0;
    transform: translateY(-50%) translateX(20px);
}

/* 页面顶部：显示文字，隐藏图标 */
.nav:not(.scrolled) .nav-logo-img {
    opacity: 0;
    transform: translateX(-20px) scale(0.9);
}

.nav:not(.scrolled) .nav-logo-text {
    opacity: 1;
    transform: translateY(-50%) translateX(0);
}

.nav-links {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    flex-wrap: nowrap;
    gap: 0;
    list-style: none;
    margin: 0;
    padding: 0;
    text-align: left;
}

.nav-links li {
    margin: 0 var(--space-2);
    padding: 0;
    height: var(--header-height);
    display: flex;
    align-items: center;
}

.nav-links a {
    color: var(--color-text);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    line-height: normal;
    border-bottom: none;
    transition: color var(--dur) var(--ease);
    position: relative;
    text-align: left;
}

/* 非"产品"下拉按钮的链接：固定尺寸 */
.nav-links > li > a:not(.nav-dropdown-toggle) {
    width: 72px;
    height: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--dur) var(--ease);
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-dropdown {
    position: relative;
}

.nav-dropdown-toggle {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    font-size: 18px;
    transition: background var(--dur) var(--ease);
}

.nav-dropdown-toggle:hover {
    background: var(--brand-alpha-08);
}

.nav-dropdown-toggle::after {
    display: none;
}

.nav-dropdown-menu {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(0);
    width: 280px;
    height: 138px;
    background: var(--surface-page);
    backdrop-filter: blur(20px);
    border: 1px solid var(--brand-alpha-12);
    border-radius: 0;
    padding: var(--space-1) var(--space-1);
    margin: 0;
    list-style: none;
    opacity: 0;
    visibility: hidden;
    transition: all var(--dur) cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow:
        0 20px 50px rgba(25, 118, 210, 0.15),
        0 0 0 1px rgba(255, 255, 255, 0.5) inset,
        0 0 30px rgba(25, 118, 210, 0.08);
    z-index: var(--z-nav-dropdown);
    box-sizing: border-box;
}

.nav-dropdown-menu::before {
    content: '';
    position: absolute;
    top: -8px;
    left: 50%;
    transform: translateX(-50%);
    border: 8px solid transparent;
    border-bottom-color: var(--brand-alpha-12);
}

.nav-dropdown-menu::after {
    content: '';
    position: absolute;
    top: -6px;
    left: 50%;
    transform: translateX(-50%);
    border: 7px solid transparent;
    border-bottom-color: var(--surface-page);
}

.nav-dropdown:hover .nav-dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.nav-dropdown-menu li {
    padding: 0;
    margin: 0;
}

.nav-dropdown-menu li + li {
    margin-top: var(--space-2);
}

.nav-dropdown-menu a {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    width: 270px;
    height: 60px;
    padding: 0 var(--space-4);
    font-size: var(--font-size-footer);
    font-weight: 500;
    color: var(--color-text-muted);
    text-decoration: none;
    transition: all var(--dur-fast) var(--ease);
    white-space: nowrap;
    border-radius: 0;
    position: relative;
    overflow: hidden;
    box-sizing: border-box;
}

.nav-dropdown-menu a::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(25, 118, 210, 0.1), rgba(66, 133, 244, 0.06));
    opacity: 0;
    transition: opacity var(--dur-fast) var(--ease);
}

.nav-dropdown-menu a:hover {
    color: var(--color-text);
}

.nav-dropdown-menu a:hover::before {
    opacity: 1;
}

.nav-dropdown-menu a::after {
    display: none;
}

.nav-dropdown-menu a .menu-icon {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0.7;
    flex-shrink: 0;
}

.nav-dropdown-menu a:hover .menu-icon {
    opacity: 1;
}

.nav-dropdown-menu a .menu-text {
    display: flex;
    flex-direction: column;
    gap: 2px;
    flex: 1;
    min-width: 0;
}

.nav-dropdown-menu a .menu-title {
    font-size: var(--font-size-footer);
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.3;
}

.nav-dropdown-menu a .menu-subtitle {
    font-size: var(--font-size-footer);
    font-weight: 400;
    color: var(--text-faint);
    line-height: 1.3;
}

.nav-dropdown-menu a .menu-platforms {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    flex-shrink: 0;
    margin-left: auto;
    align-self: center;
}

.nav-dropdown-menu a .menu-platforms svg {
    width: var(--font-size-footer);
    height: var(--font-size-footer);
    color: var(--text-faint);
    opacity: 0.7;
}

.nav-cta {
    padding: var(--space-3) var(--space-6);
    background: linear-gradient(135deg, var(--brand-primary) 0%, var(--brand-primary-soft) 100%);
    color: white !important;
    border-radius: var(--radius-md);
    font-weight: 600;
    transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 var(--space-2) var(--space-6) rgba(25, 118, 210, 0.4);
}

.nav-cta::after {
    display: none;
}

.nav.scrolled {
    background: rgba(255, 255, 255, 0.95);
}

/* Mobile Menu */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: var(--space-2);
    z-index: var(--z-nav-overlay);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    transition: all var(--dur) var(--ease);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}


/* ===== 已删除从 style.css 复制的 KS100 风格页眉样式（header / .logo / nav / .ks100-nav / .dropdown 系列，~165 行） ===== */
/* Kyroc 风格页面不使用上述 class，KS100/KS200 风格由 style.css 提供。 */

@media (max-width: 768px) {
    .nav {
        margin: 0 !important;
        padding: 0 !important;
        height: auto !important;
        position: fixed !important;
        top: 0 !important;
        left: 0 !important;
        right: 0 !important;
        z-index: var(--z-toast) !important;
        box-shadow: none !important;
        display: block !important;
    }

    .nav-logo {
        display: none;
    }
    .nav-links {
        display: none;
    }
    .mobile-menu-btn {
        display: none !important;
    }
    .desktop-menu {
        display: none !important;
    }
    .mobile-menu {
        display: block !important;
        width: 100%;
        margin-top: 0 !important;
    }
    .header-menu-2 {
        height: 64px !important;
        padding: 0 !important;
        margin: 0 !important;
    }
    /* 已删除从 style.css 复制的移动端 .logo/nav/nav ul 响应式（KS100 风格，Kyroc 页面未使用） */
}

@media (min-width: 769px) {
    .mobile-menu {
        display: none !important;
    }
    /* 桌面端页眉内容区限宽 1800px 并水平居中，背景横条保持全宽。
       .nav 为 position:fixed; left:0; right:0 全宽，用左右 padding 将内容推到 1800px 内，
       同时保留 base 规则中的 --space-10 最小边距。 */
    .nav {
        left: 0;
        right: 0;
        transform: none;
        width: 100%;
        max-width: none;
        padding: 0 max(var(--space-10), calc((100% - 1800px) / 2));
    }
}