/**
 * ZOTEQ Navigation Styles
 * 公共导航栏样式，支持深色/浅色主题
 */

/* ========== BASE NAVIGATION ========== */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: calc(var(--space-unit) * 4) calc(var(--space-unit) * 7);
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
    transition: padding 0.5s var(--ease-out-expo), 
                background 0.5s ease, 
                box-shadow 0.5s ease;
}

.main-nav .nav-center {
    display: flex;
    align-items: center;
    justify-content: space-around;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 70%;
    max-width: 900px;
}

/* ========== SCrolled STATE ========== */
.main-nav.scrolled {
    padding: calc(var(--space-unit) * 2) calc(var(--space-unit) * 7);
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(24px) saturate(180%);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.08);
}

.main-nav.scrolled .logo-svg path,
.main-nav.scrolled .logo-svg polygon {
    fill: #2d2d2d;
}

.main-nav.scrolled .nav-center a {
    color: #2d2d2d;
}

.main-nav.scrolled .nav-center a:hover {
    color: #e07a5f;
}

.main-nav.scrolled .search-container {
    background: rgba(0, 0, 0, 0.05);
    border-color: rgba(0, 0, 0, 0.1);
}

.main-nav.scrolled .search-icon {
    color: #5a5a5a;
}

.main-nav.scrolled .search-input {
    color: #2d2d2d;
}

.main-nav.scrolled .search-input::placeholder {
    color: #999;
}

/* ========== LOGO ========== */
.main-nav .logo {
    display: inline-flex;
    align-items: center;
    height: 32px;
    text-decoration: none;
    transition: transform 0.4s var(--ease-out-expo);
}

.main-nav .logo svg {
    height: 100%;
    width: auto;
}

.main-nav .logo-svg path,
.main-nav .logo-svg polygon {
    transition: fill 0.5s ease;
}

.main-nav .logo:hover {
    transform: scale(1.03);
}

/* ========== NAV LINKS ========== */
.main-nav .nav-links {
    display: flex;
    gap: calc(var(--space-unit) * 6);
    list-style: none;
}

.main-nav .nav-links a {
    text-decoration: none;
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.06em;
    transition: color 0.35s ease;
    position: relative;
    padding: 10px 0;
}

.main-nav .nav-links a::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 0;
    width: 100%;
    height: 1.5px;
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.5s var(--ease-out-expo);
}

.main-nav .nav-links a:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

/* ========== SEARCH CONTAINER ========== */
.main-nav .search-container {
    position: relative;
    display: flex;
    align-items: center;
    border-radius: 12px;
    padding: 8px 14px;
    border: 1px solid;
    transition: all 0.35s ease;
}

.main-nav .search-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    flex-shrink: 0;
}

.main-nav .search-input {
    background: transparent;
    border: none;
    outline: none;
    font-size: 0.75rem;
    width: 180px;
    padding: 6px 0 6px 28px;
}

.main-nav .search-input::placeholder {
    transition: color 0.35s ease;
}

/* ========== NAV CTA BUTTON ========== */
.main-nav .nav-cta {
    padding: 14px 28px;
    text-decoration: none;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    border-radius: 100px;
    transition: all 0.35s ease;
    position: relative;
    overflow: hidden;
}

.main-nav .nav-cta::before {
    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 ease;
}

.main-nav .nav-cta:hover::before {
    left: 100%;
}

.main-nav .nav-cta:active {
    transform: translateY(-1px);
}

/* ========== DARK THEME (DEFAULT) - 置顶时白字透明底 ========== */
.main-nav.dark-theme {
    background: transparent;
}

.main-nav.dark-theme .logo-svg path,
.main-nav.dark-theme .logo-svg polygon {
    fill: var(--white);
}

.main-nav.dark-theme .nav-links a {
    color: rgba(255, 255, 255, 0.9);
}

.main-nav.dark-theme .nav-links a:hover {
    color: var(--accent-light);
}

.main-nav.dark-theme .nav-links a::after {
    background: var(--accent-light);
}

.main-nav.dark-theme .search-container {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

.main-nav.dark-theme .search-icon {
    color: rgba(255, 255, 255, 0.7);
}

.main-nav.dark-theme .search-input {
    color: var(--white);
}

.main-nav.dark-theme .search-input::placeholder {
    color: rgba(255, 255, 255, 0.5);
}

.main-nav.dark-theme .search-container:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
}

.main-nav.dark-theme .nav-cta {
    background: rgba(255, 255, 255, 0.15);
    color: var(--white);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.main-nav.dark-theme .nav-cta:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-3px);
}

/* ========== DARK THEME SCROLLED - 滚动后白底黑字 ========== */
.main-nav.dark-theme.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(24px) saturate(180%);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.08);
}

.main-nav.dark-theme.scrolled .logo-svg path,
.main-nav.dark-theme.scrolled .logo-svg polygon {
    fill: var(--text-primary);
}

.main-nav.dark-theme.scrolled .nav-links a {
    color: var(--text-secondary);
}

.main-nav.dark-theme.scrolled .nav-links a:hover {
    color: var(--accent);
}

.main-nav.dark-theme.scrolled .nav-links a::after {
    background: var(--accent);
}

.main-nav.dark-theme.scrolled .search-container {
    background: rgba(0, 0, 0, 0.04);
    border-color: rgba(0, 0, 0, 0.1);
}

.main-nav.dark-theme.scrolled .search-icon {
    color: var(--text-tertiary);
}

.main-nav.dark-theme.scrolled .search-input {
    color: var(--text-primary);
}

.main-nav.dark-theme.scrolled .search-input::placeholder {
    color: var(--text-tertiary);
}

.main-nav.dark-theme.scrolled .search-container:hover {
    background: rgba(0, 0, 0, 0.08);
    border-color: rgba(0, 0, 0, 0.15);
}

.main-nav.dark-theme.scrolled .nav-cta {
    background: var(--accent);
    color: var(--white);
    border: none;
}

.main-nav.dark-theme.scrolled .nav-cta:hover {
    background: var(--accent-dark);
    transform: translateY(-3px);
    box-shadow: 0 16px 40px rgba(224, 122, 95, 0.4);
}

/* ========== LIGHT THEME ========== */
.main-nav.light-theme {
    background: transparent;
}

.main-nav.light-theme .logo-svg path,
.main-nav.light-theme .logo-svg polygon {
    fill: var(--text-primary);
}

.main-nav.light-theme .nav-links a {
    color: var(--text-secondary);
}

.main-nav.light-theme .nav-links a:hover {
    color: var(--accent);
}

.main-nav.light-theme .nav-links a::after {
    background: var(--accent);
}

.main-nav.light-theme .search-container {
    background: rgba(0, 0, 0, 0.04);
    border-color: rgba(0, 0, 0, 0.1);
}

.main-nav.light-theme .search-icon {
    color: var(--text-tertiary);
}

.main-nav.light-theme .search-input {
    color: var(--text-primary);
}

.main-nav.light-theme .search-input::placeholder {
    color: var(--text-tertiary);
}

.main-nav.light-theme .search-container:hover {
    background: rgba(0, 0, 0, 0.08);
    border-color: rgba(0, 0, 0, 0.15);
}

.main-nav.light-theme .nav-cta {
    background: var(--accent);
    color: var(--white);
}

.main-nav.light-theme .nav-cta:hover {
    background: var(--accent-dark);
    transform: translateY(-3px);
    box-shadow: 0 16px 40px rgba(224, 122, 95, 0.3);
}

.main-nav.light-theme.scrolled {
    background: rgba(250, 249, 247, 0.92);
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

/* ========== MOBILE MENU ========== */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    color: var(--white);
}

.main-nav.dark-theme .mobile-menu-btn {
    color: var(--white);
}

.main-nav.light-theme .mobile-menu-btn {
    color: var(--text-primary);
}

.mobile-menu-btn svg {
    width: 24px;
    height: 24px;
    transition: transform 0.3s ease;
}

.mobile-menu-btn.active svg {
    transform: rotate(90deg);
}

/* ========== RESPONSIVE ========== */
@media (max-width: 1200px) {
    .main-nav {
        padding: calc(var(--space-unit) * 3) calc(var(--space-unit) * 4);
    }

    .main-nav .nav-center {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--bg-primary);
        flex-direction: column;
        justify-content: center;
        gap: calc(var(--space-unit) * 4);
        transform: none;
        z-index: -1;
    }

    .main-nav.mobile-open .nav-center {
        display: flex;
        z-index: 99;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
    }

    .mobile-menu-btn {
        display: flex;
        z-index: 101;
        position: relative;
    }

    .main-nav.mobile-open .mobile-menu-btn {
        z-index: 102;
    }

    .main-nav .nav-links {
        flex-direction: column;
        align-items: center;
        gap: calc(var(--space-unit) * 3);
    }

    .main-nav .nav-links a {
        font-size: 1.25rem;
        padding: calc(var(--space-unit) * 2);
    }

    /* 移动端菜单打开时的链接颜色 */
    .main-nav.mobile-open .nav-links a {
        color: var(--text-primary);
    }

    .main-nav.mobile-open .nav-links a:hover {
        color: var(--accent);
    }

    .main-nav.mobile-open .nav-links a::after {
        background: var(--accent);
    }

    .main-nav .search-container {
        max-width: 280px;
        margin: 0 auto;
    }

    .main-nav .search-input {
        width: 200px;
    }
    
    /* 确保搜索框在移动端菜单中始终可见 */
    .main-nav.mobile-open .search-container {
        display: flex;
    }

    .main-nav .nav-cta {
        position: relative;
        z-index: 102;
    }
}

@media (max-width: 768px) {
    .main-nav .nav-cta {
        padding: 12px 20px;
        font-size: 0.7rem;
    }
}

/* ========== REDUCED MOTION ========== */
@media (prefers-reduced-motion: reduce) {
    .main-nav,
    .main-nav .logo,
    .main-nav .nav-links a,
    .main-nav .nav-links a::after,
    .main-nav .search-container,
    .main-nav .nav-cta,
    .main-nav .nav-cta::before,
    .mobile-menu-btn .hamburger {
        transition: none;
        animation: none;
    }
}