:root {
    --color-primary: #000000;
    --color-secondary: #666666;
    --color-tertiary: #999999;
    --color-light: #eeeeee;
    --color-background: #ffffff;
    --font-sans: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --header-height: 45px;
    --subnav-height: 35px;
    --spacing-large: 40px;
    --spacing-medium: 20px;
    --spacing-small: 10px;
    --transition-speed: 300ms;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-background);
    color: var(--color-primary);
    line-height: 1.6;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-light);
    z-index: 1000;
}

.header-content {
    display: flex;
    align-items: center;
    height: var(--header-height);
    padding: 0 30px;
}

.logo {
    font-size: 30px;
    font-weight: 800;
    color: var(--color-primary);
    letter-spacing: 0.1em;
    text-align: left;
}

.logo span {
    font-family: "Trebuchet MS", Helvetica, sans-serif;
    box-shadow: none;
    display: inline-block;
}

.main-nav {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
}

.main-categories {
    display: flex;
    list-style: none;
    gap: 40px;
    padding: 4px 0;
    position: relative;
}

.main-categories::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(0,0,0,0.08), transparent);
}

.category-item {
    position: relative;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 0;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.category-item .marker {
    opacity: 0;
    color: var(--color-primary);
    font-size: 8px;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    transform: scale(0);
}

.category-item.active .marker {
    opacity: 1;
    transform: scale(1);
}

.category-item .category-text {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    white-space: nowrap;
}

.category-item .category-text::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.category-item:hover .category-text {
    color: var(--color-secondary);
}

.category-item:hover .category-text::after {
    width: 100%;
}

.category-item.active .category-text {
    color: var(--color-primary);
    font-weight: 600;
}

.category-item.active .category-text::after {
    width: 100%;
    background: linear-gradient(90deg, var(--color-primary), rgba(0,0,0,0.3));
}

.category-item:hover {
    transform: translateY(-2px);
}

.category-item:active {
    transform: translateY(0);
}

.sub-nav {
    background: linear-gradient(135deg, rgba(255,255,255,0.9) 0%, rgba(255,255,255,0.7) 100%);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
    box-shadow: 0 2px 20px rgba(0,0,0,0.03);
}

.sub-categories {
    display: flex;
    list-style: none;
    gap: 20px;
    padding: 10px 30px;
    overflow-x: auto;
    scrollbar-width: none;
    justify-content: center;
    position: relative;
}

.sub-categories::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 2px;
    background: linear-gradient(90deg, transparent, rgba(0,0,0,0.1), transparent);
}

.sub-categories::-webkit-scrollbar {
    display: none;
}

.sub-item {
    font-size: 13px;
    color: var(--color-tertiary);
    cursor: pointer;
    padding: 8px 16px;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    white-space: nowrap;
    font-weight: 500;
    position: relative;
    border-radius: 10px;
    background: transparent;
    overflow: hidden;
}

.sub-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--color-primary) 0%, #333 100%);
    border-radius: 10px;
    opacity: 0;
    transform: scale(0.8);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    z-index: -1;
}

.sub-item:hover {
    color: var(--color-primary);
    transform: translateY(-3px) scale(1.05);
    text-shadow: 0 0 20px rgba(0,0,0,0.15);
}

.sub-item:hover::before {
    opacity: 0.08;
    transform: scale(1);
}

.sub-item::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 80%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--color-primary), transparent);
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.sub-item:hover::after {
    transform: translateX(-50%) scaleX(1);
}

.sub-item.active {
    color: var(--color-primary);
    font-weight: 600;
    background: linear-gradient(135deg, rgba(0,0,0,0.01) 0%, rgba(0,0,0,0.02) 100%);
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
    animation: pulse-glow 2s ease-in-out infinite;
}

.sub-item.active::before {
    opacity: 0.06;
    transform: scale(1);
}

.sub-item.active::after {
    transform: translateX(-50%) scaleX(1);
    background: var(--color-primary);
}

@keyframes pulse-glow {
    0%, 100% {
        box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    }
    50% {
        box-shadow: 0 2px 20px rgba(0,0,0,0.15);
    }
}

.sub-item:active {
    transform: translateY(-1px) scale(0.98);
}

.main-content {
    padding-top: calc(var(--header-height) + var(--subnav-height) + var(--spacing-large));
    padding-bottom: var(--spacing-large);
}

.works-section {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 25%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    position: relative;
}

.work-item {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: var(--spacing-large);
    animation: fadeIn 0.5s ease forwards;
    position: relative;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.work-info {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    margin-bottom: var(--spacing-small);
    position: relative;
    z-index: 1000;
}

.work-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-primary);
    margin-bottom: 3px;
    line-height: 1.4;
}

.work-location {
    font-size: 10px;
    font-weight: 400;
    color: var(--color-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.work-image-wrapper {
    width: 100%;
    overflow: hidden;
    cursor: pointer;
    position: relative;
    z-index: 2;
    aspect-ratio: 16 / 9;
}

.work-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform var(--transition-speed) ease;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
    -webkit-user-drag: none;
    pointer-events: auto;
}

.work-image:hover {
    transform: scale(1.02);
}

.work-item.expanded .work-image-wrapper {
    position: relative;
    overflow: visible;
}

.gallery-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    display: flex;
    overflow-x: auto;
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    z-index: 999;
    cursor: grab;
    gap: 20px;
    padding: 0 0 20px 0;
}

.gallery-container:active {
    cursor: grabbing;
}

.gallery-container::-webkit-scrollbar {
    display: none;
}

.gallery-image {
    flex-shrink: 0;
    height: 400px;
    width: auto;
    object-fit: contain;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
    -webkit-user-drag: none;
}



.nav-arrow {
    position: absolute;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    color: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(0, 0, 0, 0.2);
    background: rgba(255, 255, 255, 0.1);
    cursor: pointer;
    z-index: 1001;
    transition: opacity 0.3s ease;
    user-select: none;
    opacity: 0.3;
    transform: translateY(-50%);
}

.nav-arrow:hover {
    color: rgba(0, 0, 0, 0.8);
    border-color: rgba(0, 0, 0, 0.5);
    background: rgba(255, 255, 255, 0.9);
}

.close-gallery {
    position: fixed;
    top: calc(var(--header-height));
    right: 40px;
    width: 40px;
    height: 40px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    font-size: 24px;
    z-index: 1001;
    display: none;
    align-items: center;
    justify-content: center;
    transition: background 0.3s ease;
}

.close-gallery:hover {
    background: rgba(0, 0, 0, 0.9);
}

.close-gallery.active {
    display: flex;
}

@media (max-width: 768px) {
    :root {
        --spacing-large: 35px;
    }

    .header-content {
        padding: 0 20px;
        flex-wrap: wrap;
        gap: 5px;
        height: auto;
        padding-bottom: 5px;
    }

    .logo {
        font-size: 21px;
        width: 100%;
        text-align: left;
    }

    .main-nav {
        position: static;
        transform: none;
        left: auto;
        width: 100%;
    }

    .main-categories {
        gap: 20px;
        padding: 4px 20px;
        flex-wrap: nowrap;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        justify-content: center;
    }

    .main-categories::-webkit-scrollbar {
        display: none;
    }

    .category-item {
        white-space: nowrap;
        flex-shrink: 0;
        padding: 4px 0;
    }

    .sub-categories {
        padding: 6px 20px;
        gap: 20px;
        flex-wrap: nowrap;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        justify-content: center;
    }

    .sub-categories::-webkit-scrollbar {
        display: none;
    }

    .main-content {
        padding-top: calc(var(--header-height) + var(--subnav-height) + var(--spacing-large));
    }

    .works-section {
        padding: 0 10%;
    }

    .work-item {
        flex-direction: column;
        width: 100%;
    }

    .work-info {
        width: 100%;
        align-items: center;
        text-align: center;
        order: 0;
    }

    .work-title {
        font-size: 12px;
    }

    .work-image-wrapper {
        width: 100%;
        order: 1;
    }

    .gallery-image {
        width: 100vw;
    }

    .close-gallery {
        right: 0;
        top: 0;
    }
}

@media screen and (max-width: 480px) {
    :root {
        --spacing-large: 35px;
    }

    .header-content {
        padding: 0 15px;
        flex-direction: column;
        align-items: stretch;
        gap: 3px;
        height: auto;
        padding-bottom: 3px;
    }

    .logo {
        font-size: 21px;
        width: 100%;
        text-align: left;
    }

    .main-nav {
        width: 100%;
    }

    .main-categories {
        padding: 3px 15px;
        gap: 15px;
        flex-wrap: nowrap;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        justify-content: flex-start;
    }

    .main-categories::-webkit-scrollbar {
        display: none;
    }

    .category-item .category-text {
        font-size: 11px;
        white-space: nowrap;
    }

    .category-item {
        flex-shrink: 0;
        padding: 4px 0;
    }

    .sub-categories {
        padding: 5px 15px;
        gap: 10px;
        flex-wrap: nowrap;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        justify-content: center;
    }

    .sub-categories::-webkit-scrollbar {
        display: none;
    }

    .sub-item {
        font-size: 10px;
        white-space: nowrap;
        padding: 6px 10px;
    }

    .works-section {
        padding: 0 15px;
    }

    .work-title {
        font-size: 14px;
    }

    .work-location {
        font-size: 10px;
    }

    .work-item {
        flex-direction: column;
        width: 100%;
    }

    .work-image-wrapper {
        width: 100%;
    }

    .gallery-container {
        position: relative;
        width: 100%;
        height: auto;
        display: none;
        flex-direction: row;
        overflow-x: auto;
        scroll-behavior: smooth;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        z-index: 999;
        gap: 10px;
        padding: 10px 0;
    }

    .gallery-container::-webkit-scrollbar {
        display: none;
    }

    .gallery-image {
        flex-shrink: 0;
        height: auto;
        width: auto;
        max-height: none;
        object-fit: cover;
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        user-select: none;
        -webkit-user-drag: none;
    }

    .work-item.expanded {
        height: auto !important;
    }

    .work-item.expanded .gallery-container {
        display: flex;
    }

    .work-item:not(.expanded) .gallery-container {
        display: none;
    }

    .close-gallery {
        right: 0;
        top: 0;
    }
}

/* 滑动指示器样式 - 全局可用 */
.scroll-indicator-track {
    width: 100%;
    height: 3px;
    background: rgba(128, 128, 128, 0.2);
    border-radius: 2px;
    position: relative;
    margin: 8px 0;
    cursor: pointer;
    overflow: hidden;
}

.scroll-indicator-thumb {
    height: 100%;
    background: rgba(128, 128, 128, 0.5);
    border-radius: 2px;
    position: absolute;
    top: 0;
    left: 0;
    transition: width 0.1s ease;
}

/* ===== 开场动画 ===== */
#splash-screen {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 99999;
    pointer-events: none;
}

#splash-logo {
    font-size: 60px;
    font-weight: 800;
    color: var(--color-primary);
    letter-spacing: 0.1em;
    font-family: "Trebuchet MS", Helvetica, sans-serif;
}