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

input:focus,
input:focus-visible,
select:focus,
select:focus-visible,
textarea:focus,
textarea:focus-visible {
    outline: none;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    color: #fff;
}
.page {
    height: 100vh;
    overflow-y: scroll;
    scroll-snap-type: y mandatory;
    scroll-behavior: smooth;
}

.section {
    height: 100vh;
    scroll-snap-align: start;
    display: flex;
    justify-content: center;
    align-items: center;
}

/*  第一屏  */
.hero {
    height: 100vh;
    background-image: url(../images/bgimg1.PNG);
    background-size: cover;
    background-position: center;
    position: relative;
}

/*  顶部导航  */
.nav {
    position: fixed;
    top: 60px;
    border-radius: 999px;
    width: 100%;
    display: flex;
    justify-content: center;
    z-index: 1000;
}

.nav-inner {
    position: relative;
    display: flex;
    align-items: center;
    gap: 80px;
    padding: 8px 100px;
    background: rgba(255, 255, 255, 0.18);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 
        0 8px 3-px rgba(0, 0, 0, 0.12);
        inset: 0 1px 0 rgba(255, 255, 255, 0.45);
    color: #fff;
    font-size: 16px;
}

/* 跟随鼠标的椭圆指示器 */
.nav-indicator {
    position: absolute;
    height: 36px;
    background: rgba(255, 255, 255, 0.25);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 999px;
    box-shadow: 
        inset 0 0 0 1px rgba(255, 255, 255, 0.35),
        0 4px 10px rgba(0, 0, 0, 0.15);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    pointer-events: none;
    z-index: -1;
}

.nav-item {
    flex-shrink: 0;
    position: relative;
    padding: 8px 18px;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    border-radius: 999px;
    transition: color 0.3s ease;
    white-space: nowrap;
    word-break: keep-all;
}

.nav-item:hover {
    color: #fff;
}

.nav-item.active {
    color: #fff;
    font-weight: 600;
}

.nav-inner a {
    cursor: pointer;
    color: #fff;
    text-decoration: none;
}

/*  中心内容  */
.hero-content {
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 48px;
    margin-bottom: 20px;
    letter-spacing: 10px;
}

.hero-content p {
    font-size: 16px;
    opacity: 0.9;
    margin-bottom: 10px;
    line-height: 30px;
}

.author {
    font-size: 14px;
    opacity: 0.7;
    margin-bottom: 30px;
    line-height: 40px;
}

/*  按钮  */
.buttons {
    display: flex;
    gap: 80px;
    position: relative;
    top: 40px;
}

.btn {
    padding: 12px 28px;
    border-radius: 25px;
    text-decoration: none;
    font-size: 14px;
}
.primary {
    border: 1px solid #fff;
    background: rgba(245, 166, 35, 0.4);
    color: #fff;
}
.primary:hover {
    background: #f5a623;
    color: #fff;
}

.ghost {
    border: 1px solid #fff;
    background: rgba(245, 166, 35, 0.4);
    color: #fff;
}
.ghost:hover {
    background: #f5a623;
    color: #fff;
}

/*  底部提示  */
.scroll-tip {
    position: fixed;
    left: 0;
    bottom: 30px;
    width: 100%;
    border: 0;
    background: transparent;
    color: inherit;
    font-family: inherit;
    text-align: center;
    font-size: 12px;
    opacity: 0.7;
    animation: float 2s ease-in-out infinite;
    cursor: pointer;
    z-index: 1000;
}

.scroll-tip.is-back-top {
    width: auto;
    min-width: 150px;
    min-height: 44px;
    left: auto;
    right: 50%;
    bottom: 84px;
    padding: 10px 24px;
    border: 1px solid rgba(255, 184, 91, 0.55);
    border-radius: 999px;
    background: rgba(8, 17, 34, 0.52);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    color: #ffd08a;
    font-size: 13px;
    opacity: 1;
    transform: translateX(50%);
    animation: none;
}

.scroll-tip:focus-visible {
    outline: 2px solid #fff;
    outline-offset: 4px;
}
@keyframes float {
    0% { transform: translateY(0);}
    50% { transform: translateY(6px);}
    100% { transform: translateY(0);}    
}

.hero-2 {
    height: 100vh;
    background-image: url(../images/bgimg3.png);  
    background-size: cover;
    background-position: center;
    padding: 132px 32px 56px;
}

.sec-content2 {
    width: min(100%, 920px);
    margin: 0 auto;
}

.feature-heading {
    margin-bottom: 46px;
    text-align: center;
}

.feature-heading h2 {
    margin-bottom: 10px;
    font-size: clamp(32px, 3vw, 42px);
    letter-spacing: 0.08em;
}

.feature-heading p {
    color: rgba(255, 255, 255, 0.62);
    font-size: 16px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 26px;
}

.feature-card {
    min-height: 240px;
    padding: 32px 28px 26px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 15px;
    background: rgba(255, 255, 255, 0.15);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
    transition: transform 0.25s ease, background-color 0.25s ease, border-color 0.25s ease;
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: rgba(255, 255, 255, 0.25);
    background: rgba(255, 255, 255, 0.4);
}

.feature-icon {
    display: block;
    min-height: 42px;
    margin-bottom: 15px;
    font-size: 31px;
    line-height: 1;
}

.feature-card h3 {
    margin-bottom: 10px;
    font-size: 19px;
    letter-spacing: 0.06em;
}

.feature-card p {
    min-height: 63px;
    color: rgba(255, 255, 255, 0.66);
    font-size: 13px;
    line-height: 1.7;
}

.feature-card a {
    display: inline-flex;
    min-height: 44px;
    align-items: center;
    gap: 5px;
    color: rgba(255, 255, 255, 0.58);
    font-size: 13px;
    text-decoration: none;
    transition: color 0.2s ease, gap 0.2s ease;
}

.feature-card a:hover {
    gap: 9px;
    color: #fff;
}

.feature-card a:focus-visible {
    border-radius: 4px;
    outline: 2px solid #fff;
    outline-offset: 4px;
}

.hero-3 {
    height: 100vh;
    width: 100%;
    overflow: hidden;
    position: relative;
    background-image: url(../images/bgimg4.PNG);
    background-position: center;
    background-size: cover;
    isolation: isolate;
}

.hero-3::before {
    position: absolute;
    z-index: -1;
    inset: 0;
    background: linear-gradient(180deg, rgba(4, 11, 29, 0.34), rgba(4, 11, 29, 0.18) 48%, rgba(4, 11, 29, 0.35));
    content: "";
}

.portfolio-content {
    width: 100%;
    padding: 94px 32px 24px;
}

.portfolio-heading {
    position: relative;
    z-index: 10;
    text-align: center;
}

.portfolio-heading h2 {
    margin-bottom: 10px;
    color: #fff5df;
    font-family: Georgia, "Songti SC", "STSong", serif;
    font-size: clamp(40px, 4.2vw, 64px);
    font-weight: 600;
    letter-spacing: 0.12em;
    text-shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
}

.portfolio-heading p {
    color: rgba(255, 249, 237, 0.9);
    font-size: clamp(14px, 1.4vw, 20px);
    letter-spacing: 0.18em;
    text-shadow: 0 2px 12px rgba(0, 0, 0, 0.35);
}

.portfolio-divider {
    display: block;
    width: min(260px, 40vw);
    height: 1px;
    margin: 0 auto 18px;
    position: relative;
    background: linear-gradient(90deg, transparent, #f1ad55 20%, #f1ad55 80%, transparent);
}

.portfolio-divider::after {
    width: 8px;
    height: 8px;
    position: absolute;
    top: 50%;
    left: 50%;
    border: 1px solid #ffc36d;
    background: #5f381f;
    content: "";
    transform: translate(-50%, -50%) rotate(45deg);
}

.portfolio-carousel {
    height: min(54vh, 500px);
    min-height: 390px;
    position: relative;
    margin-top: 18px;
}

.portfolio-stage {
    width: calc(100% - 150px);
    height: 100%;
    margin: 0 auto;
    overflow: hidden;
    perspective: 1300px;
    touch-action: pan-y;
}

.portfolio-track {
    width: 100%;
    height: 100%;
    position: relative;
    transform-style: preserve-3d;
}

.portfolio-card {
    width: clamp(260px, 28vw, 410px);
    height: min(49vh, 450px);
    min-height: 360px;
    overflow: hidden;
    position: absolute;
    top: 50%;
    left: 50%;
    border: 1px solid rgba(255, 191, 105, 0.55);
    border-radius: 20px;
    background: rgba(10, 18, 35, 0.76);
    box-shadow: 0 24px 60px rgba(1, 6, 18, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.16);
    opacity: 0;
    transform: translate(-50%, -50%) scale(0.7);
    transition: transform 0.55s cubic-bezier(0.2, 0.72, 0.2, 1), opacity 0.45s ease, filter 0.45s ease;
    will-change: transform, opacity;
}

.portfolio-card.is-active {
    z-index: 5;
    border-color: rgba(255, 190, 102, 0.95);
    box-shadow: 0 0 16px rgba(255, 169, 72, 0.42), 0 30px 70px rgba(1, 6, 18, 0.58), inset 0 1px 0 rgba(255, 255, 255, 0.2);
    opacity: 1;
    filter: none;
    transform: translate(-50%, -50%) translateZ(90px) scale(1);
}

.portfolio-card.is-prev,
.portfolio-card.is-next {
    z-index: 3;
    opacity: 0.88;
    filter: saturate(0.82) brightness(0.82);
}

.portfolio-card.is-prev {
    transform: translate(calc(-50% - clamp(250px, 28vw, 410px)), -50%) rotateY(14deg) scale(0.78);
}

.portfolio-card.is-next {
    transform: translate(calc(-50% + clamp(250px, 28vw, 410px)), -50%) rotateY(-14deg) scale(0.78);
}

.portfolio-card.is-far-prev,
.portfolio-card.is-far-next {
    z-index: 1;
    opacity: 0.48;
    filter: saturate(0.65) brightness(0.64) blur(0.6px);
}

.portfolio-card.is-far-prev {
    transform: translate(calc(-50% - clamp(430px, 49vw, 720px)), -50%) rotateY(18deg) scale(0.62);
}

.portfolio-card.is-far-next {
    transform: translate(calc(-50% + clamp(430px, 49vw, 720px)), -50%) rotateY(-18deg) scale(0.62);
}

.portfolio-preview {
    height: calc(100% - 64px);
    overflow: hidden;
    position: relative;
}

.portfolio-card h3 {
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-top: 1px solid rgba(255, 184, 91, 0.38);
    color: #ffc46f;
    font-family: Georgia, "Songti SC", serif;
    font-size: 24px;
    letter-spacing: 0.1em;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.45);
}

.preview-graphic {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(160deg, #c17d59 0%, #8c4d3e 46%, #25354a 100%);
}

.preview-graphic strong {
    z-index: 1;
    color: rgba(255, 238, 206, 0.88);
    font-family: Georgia, serif;
    font-size: clamp(32px, 4vw, 56px);
    font-weight: 400;
    line-height: 0.96;
}

.poster-sun {
    width: 120px;
    height: 120px;
    position: absolute;
    right: 8%;
    bottom: 12%;
    border-radius: 50%;
    background: rgba(241, 171, 97, 0.6);
    box-shadow: -90px 45px 0 25px rgba(37, 53, 74, 0.58);
}

.preview-sketch {
    background-color: #e8dcc8;
    background-image: repeating-linear-gradient(20deg, transparent 0 20px, rgba(78, 67, 57, 0.08) 21px), linear-gradient(145deg, transparent 50%, rgba(77, 68, 57, 0.14));
}

.sketch-line {
    height: 2px;
    position: absolute;
    left: 14%;
    background: #6e6258;
    box-shadow: 18px 12px 0 rgba(80, 70, 61, 0.62), 46px -20px 0 rgba(80, 70, 61, 0.52);
    transform-origin: left;
}

.sketch-line-one { width: 72%; top: 30%; transform: rotate(-22deg); }
.sketch-line-two { width: 68%; top: 52%; transform: rotate(18deg); }
.sketch-line-three { width: 76%; top: 68%; transform: rotate(-8deg); }

.preview-app {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 12px;
    padding: 34px 26px 18px;
    background: radial-gradient(circle at 50% 25%, rgba(81, 101, 145, 0.45), transparent 48%), #0b1324;
}

.app-phone,
.app-dashboard {
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 22px;
    background: linear-gradient(160deg, #17233a, #0c1424);
    box-shadow: 0 14px 28px rgba(0, 0, 0, 0.28);
}

.app-phone {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    transform: rotate(-5deg);
}

.phone-notch {
    width: 38%;
    height: 12px;
    position: absolute;
    top: 8px;
    border-radius: 10px;
    background: #050910;
}

.app-phone small { color: #b9c3d5; }
.app-phone > strong { margin: 10px 0; color: #fff; font-size: 28px; }

.app-ring {
    width: 92px;
    height: 92px;
    border: 9px solid rgba(255, 154, 54, 0.18);
    border-top-color: #ff9c3d;
    border-right-color: #ff9c3d;
    border-radius: 50%;
}

.app-dashboard {
    display: grid;
    grid-template-rows: 1fr 0.8fr 0.8fr;
    gap: 9px;
    padding: 13px;
}

.chart-title { color: #d8dfeb; font-size: 11px; }

.chart-line {
    border-bottom: 2px solid #7c8cff;
    border-radius: 50%;
    transform: rotate(-8deg);
}

.dashboard-stat {
    padding: 9px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.045);
    color: #98a5ba;
    font-size: 10px;
}

.dashboard-stat strong { color: #fff; font-size: 13px; }

.preview-web {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 38px;
    background: linear-gradient(rgba(5, 18, 33, 0.24), rgba(5, 18, 33, 0.56)), url(../images/bgimg4.PNG) center/cover;
}

.web-nav {
    width: 70%;
    height: 5px;
    position: absolute;
    top: 25px;
    left: 15%;
    border-top: 1px solid rgba(255, 255, 255, 0.48);
}

.preview-web strong { color: #fff; font-size: 26px; }
.preview-web small { margin: 8px 0 18px; color: rgba(255,255,255,.72); }

.web-button {
    width: fit-content;
    padding: 8px 14px;
    border-radius: 4px;
    background: #e88f32;
    color: #fff;
    font-size: 10px;
}

.web-grid {
    height: 50px;
    margin-top: 26px;
    border-radius: 6px;
    background: repeating-linear-gradient(90deg, rgba(255,255,255,.14) 0 26%, transparent 26% 30%);
}

.preview-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(145deg, #242938, #111725);
}

.preview-brand small { position: absolute; top: 28px; left: 28px; color: #b1a895; }
.preview-brand strong { color: #aa9279; font-family: Georgia, serif; font-size: 74px; line-height: 0.62; letter-spacing: -0.1em; }

.portfolio-arrow {
    width: 58px;
    height: 58px;
    display: grid;
    place-items: center;
    position: absolute;
    z-index: 10;
    top: 50%;
    border: 1px solid rgba(255, 181, 86, 0.8);
    border-radius: 50%;
    background: rgba(7, 15, 30, 0.46);
    color: #fff7e9;
    cursor: pointer;
    transform: translateY(-50%);
    transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.portfolio-arrow span { margin-top: -5px; font-family: serif; font-size: 48px; line-height: 1; }
.portfolio-arrow-prev { left: 12px; }
.portfolio-arrow-next { right: 12px; }

.portfolio-arrow:hover {
    border-color: #ffc26c;
    background: rgba(222, 127, 38, 0.32);
    transform: translateY(-50%) scale(1.06);
}

.portfolio-arrow:focus-visible,
.portfolio-dot:focus-visible {
    outline: 2px solid #fff;
    outline-offset: 4px;
}

.portfolio-dots {
    min-height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-top: 1px;
}

.portfolio-dot {
    width: 12px;
    height: 12px;
    padding: 0;
    border: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.55);
    cursor: pointer;
    transition: transform 0.25s ease, background-color 0.25s ease;
}

.portfolio-dot.is-active {
    background: #ffac4e;
    box-shadow: 0 0 14px rgba(255, 164, 66, 0.8);
    transform: scale(1.45);
}

.portfolio-status {
    width: 1px;
    height: 1px;
    overflow: hidden;
    position: absolute;
    clip-path: inset(50%);
    white-space: nowrap;
}

/* 第四屏：技术支持 */
.hero-4 {
    min-height: 100vh;
    height: 100vh;
    width: 100%;
    overflow: hidden;
    position: relative;
    background-image: url(../images/bgimg5.png);
    background-position: center;
    background-size: cover;
    isolation: isolate;
}

.hero-4::before {
    position: absolute;
    z-index: -1;
    inset: 0;
    background: linear-gradient(180deg, rgba(4, 10, 27, 0.18), rgba(4, 10, 27, 0.28) 55%, rgba(4, 10, 27, 0.5));
    content: "";
}

.support-content {
    width: min(100%, 1040px);
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0 auto;
    padding: 100px 24px 24px;
}

.support-main {
    width: 100%;
    min-height: 0;
    display: flex;
    flex: 1;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 24px 0 44px;
}

.support-heading {
    text-align: center;
}

.support-heading h2 {
    margin-bottom: 10px;
    color: #fff;
    font-size: clamp(34px, 3.2vw, 46px);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-shadow: 0 3px 18px rgba(0, 0, 0, 0.35);
}

.support-heading p {
    color: rgba(255, 255, 255, 0.72);
    font-size: 15px;
}

.support-divider {
    display: block;
    width: 250px;
    height: 1px;
    margin: 0 auto 17px;
    position: relative;
    background: linear-gradient(90deg, transparent, rgba(242, 165, 74, 0.9), transparent);
}

.support-divider::after {
    width: 7px;
    height: 7px;
    position: absolute;
    top: 50%;
    left: 50%;
    border: 1px solid #ffb45d;
    background: #6e4124;
    content: "";
    transform: translate(-50%, -50%) rotate(45deg);
}

.support-grid {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 26px;
    margin-top: 42px;
}

.support-card {
    min-height: 190px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 24px 16px;
    border: 1px solid rgba(255, 184, 91, 0.52);
    border-radius: 16px;
    background: rgba(11, 20, 40, 0.62);
    backdrop-filter: blur(13px);
    -webkit-backdrop-filter: blur(13px);
    box-shadow: 0 16px 38px rgba(1, 6, 18, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    transition: transform 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}

.support-card:hover {
    border-color: rgba(255, 192, 105, 0.9);
    background: rgba(16, 28, 51, 0.72);
    transform: translateY(-5px);
}

.support-icon {
    width: 68px;
    height: 68px;
    display: grid;
    place-items: center;
    margin-bottom: 18px;
    border: 1px solid rgba(255, 186, 92, 0.72);
    border-radius: 16px;
    background: rgba(255, 157, 48, 0.08);
    box-shadow: 0 0 20px rgba(255, 152, 44, 0.2), inset 0 0 14px rgba(255, 167, 64, 0.08);
}

.support-icon svg {
    width: 38px;
    height: 38px;
    fill: none;
    stroke: #ffb458;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 2.2;
}

.support-card h3 {
    margin-bottom: 8px;
    color: #fff;
    font-size: 16px;
    letter-spacing: 0.03em;
}

.support-card p {
    color: rgba(255, 255, 255, 0.62);
    font-size: 13px;
}

.support-notes {
    margin-top: 34px;
    text-align: center;
}

.support-notes p {
    color: rgba(255, 255, 255, 0.72);
    font-size: 14px;
    line-height: 2;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.4);
}

.site-footer {
    width: min(100%, 960px);
    flex: 0 0 auto;
    margin-top: 0;
    padding-top: 18px;
    border-top: 1px solid rgba(255, 184, 91, 0.28);
    text-align: center;
}

.site-footer p {
    color: rgba(255, 255, 255, 0.48);
    font-size: 12px;
    line-height: 1.9;
}

.site-footer a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s ease;
}

.site-footer a:hover {
    color: rgba(255, 255, 255, 0.82);
}

.site-footer a:focus-visible {
    border-radius: 3px;
    outline: 2px solid #fff;
    outline-offset: 3px;
}











































/* ==================== 响应式设计 ==================== */

/* 平板端（768px - 1024px） */
@media (max-width: 1024px) {
    .nav-inner {
        gap: 40px;
        padding: 8px 40px;
    }

    .hero-content h1 {
        font-size: 36px;
        letter-spacing: 6px;
    }

    .buttons {
        gap: 40px;
    }

    .hero-2,
    .hero-3 {
        width: 100%;
        padding: 0 20px;
    }

    .hero-2 {
        padding: 126px 24px 40px;
    }

    .feature-heading {
        margin-bottom: 28px;
    }

    .feature-grid {
        gap: 18px;
    }

    .feature-card {
        min-height: 218px;
        padding: 24px 20px 18px;
    }

    .portfolio-content {
        padding-inline: 20px;
    }

    .portfolio-stage {
        width: calc(100% - 116px);
    }

    .support-content {
        padding-top: 92px;
    }

    .support-main {
        padding-bottom: 36px;
    }

    .support-grid {
        gap: 16px;
        margin-top: 30px;
    }

    .support-card {
        min-height: 174px;
        padding-inline: 12px;
    }

    .support-notes {
        margin-top: 28px;
    }
}

/* 手机端（小于 768px） */
@media (max-width: 768px) {
    /* 导航栏适配 */
    .nav {
        top: 60px;
        padding: 0 8px;
    }
    .hero {
        background-image: url(../images/bgimg1-mobile.png);
    }
    .hero-2 {
        background-image: url(../images/bgimg3-mobile.png);
    }
    .hero-3 {
        min-height: 100svh;
        height: 100svh;
        padding: 0;
        background-image: url(../images/bgimg4-mobile.png);
    }
    .hero-4 {
        min-height: 100svh;
        height: auto;
        padding: 0;
        background-image: url(../images/bgimg5-mobile.png);
        background-position: center top;
    }


    .nav-inner {
        width: min(100%, 680px);
        justify-content: space-between;
        gap: clamp(2px, 1.2vw, 10px);
        padding: 6px clamp(6px, 2vw, 18px);
        overflow: hidden;
        font-size: clamp(10px, 3vw, 12px);
    }

    .nav-indicator {
        height: 28px;
    }

    .nav-item {
        padding: 6px clamp(4px, 1.3vw, 10px);
        font-size: inherit;
        line-height: 1;
    }

    /* 主内容适配 */
    .hero-content h1 {
        font-size: 24px;
        letter-spacing: 4px;
        margin-bottom: 12px;
    }

    .hero-content p {
        font-size: 14px;
        padding: 0 16px;
    }

    .author {
        font-size: 12px;
        line-height: 24px;
        margin-bottom: 20px;
    }

    /* 按钮适配 */
    .buttons {
        flex-direction: column;
        gap: 24px;
        top: 20px;
    }

    .btn {
        padding: 10px 24px;
        font-size: 13px;
    }

    /* 滚动提示 */
    .scroll-tip {
        font-size: 10px;
        bottom: 20px;
    }

    /* 第二、三屏 */
    .hero-2,
    .hero-3 {
        width: 100%;
        padding: 20px;
    }

    .hero-3 p {
        font-size: 18px;
    }

    .hero-2 {
        min-height: 100vh;
        height: auto;
        padding: 104px 12px 28px;
    }

    .feature-heading {
        margin-bottom: 18px;
    }

    .feature-heading h2 {
        margin-bottom: 5px;
        font-size: 25px;
    }

    .feature-heading p {
        font-size: 12px;
    }

    .feature-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 10px;
    }

    .feature-card {
        min-height: 178px;
        padding: 15px 13px 10px;
        border-radius: 12px;
    }

    .feature-icon {
        min-height: 28px;
        margin-bottom: 8px;
        font-size: 24px;
    }

    .feature-card h3 {
        margin-bottom: 6px;
        font-size: 15px;
    }

    .feature-card p {
        min-height: 69px;
        font-size: 10px;
        line-height: 1.55;
    }

    .feature-card a {
        min-height: 44px;
        font-size: 10px;
    }

    .portfolio-content {
        padding: 100px 8px 16px;
    }

    .portfolio-heading h2 {
        margin-bottom: 7px;
        font-size: clamp(34px, 11vw, 48px);
    }

    .portfolio-heading p {
        font-size: 12px;
        letter-spacing: 0.08em;
    }

    .portfolio-divider {
        margin-bottom: 12px;
    }

    .portfolio-carousel {
        height: min(54vh, 430px);
        min-height: 360px;
        margin-top: 8px;
    }

    .portfolio-stage {
        width: calc(100% - 64px);
    }

    .portfolio-card {
        width: min(72vw, 310px);
        height: min(47vh, 390px);
        min-height: 330px;
        border-radius: 16px;
    }

    .portfolio-card.is-prev {
        transform: translate(calc(-50% - 57vw), -50%) rotateY(16deg) scale(0.76);
    }

    .portfolio-card.is-next {
        transform: translate(calc(-50% + 57vw), -50%) rotateY(-16deg) scale(0.76);
    }

    .portfolio-card.is-far-prev {
        transform: translate(calc(-50% - 95vw), -50%) rotateY(18deg) scale(0.58);
    }

    .portfolio-card.is-far-next {
        transform: translate(calc(-50% + 95vw), -50%) rotateY(-18deg) scale(0.58);
    }

    .portfolio-preview {
        height: calc(100% - 54px);
    }

    .portfolio-card h3 {
        height: 54px;
        font-size: 19px;
    }

    .preview-app {
        padding: 24px 18px 14px;
    }

    .app-ring {
        width: 72px;
        height: 72px;
    }

    .portfolio-arrow {
        width: 46px;
        height: 46px;
    }

    .portfolio-arrow span {
        font-size: 39px;
    }

    .portfolio-arrow-prev { left: 2px; }
    .portfolio-arrow-next { right: 2px; }

    .portfolio-dots {
        gap: 12px;
    }

    .portfolio-dot {
        width: 10px;
        height: 10px;
    }

    .support-content {
        min-height: 100svh;
        padding: 78px 12px 20px;
    }

    .support-main {
        padding: 20px 0 34px;
    }

    .support-heading h2 {
        margin-bottom: 7px;
        font-size: 28px;
    }

    .support-heading p {
        font-size: 12px;
    }

    .support-divider {
        width: 180px;
        margin-bottom: 11px;
    }

    .support-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 10px;
        margin-top: 20px;
    }

    .support-card {
        min-height: 138px;
        padding: 14px 8px;
        border-radius: 12px;
    }

    .support-card:hover {
        transform: none;
    }

    .support-icon {
        width: 48px;
        height: 48px;
        margin-bottom: 10px;
        border-radius: 12px;
    }

    .support-icon svg {
        width: 29px;
        height: 29px;
    }

    .support-card h3 {
        margin-bottom: 5px;
        font-size: 14px;
    }

    .support-card p {
        font-size: 12px;
    }

    .support-notes {
        margin-top: 19px;
        padding-inline: 6px;
    }

    .support-notes p {
        font-size: 12px;
        line-height: 1.7;
    }

    .site-footer {
        padding-top: 12px;
    }

    .site-footer p {
        font-size: 10px;
        line-height: 1.7;
    }

    .scroll-tip.is-back-top {
        bottom: 70px;
        min-width: 132px;
        padding-inline: 18px;
        font-size: 12px;
    }
}

/* 小屏手机（小于 375px） */
@media (max-width: 375px) {
    .nav-inner {
        width: 100%;
        gap: 2px;
        padding: 4px;
    }

    .nav-item {
        padding: 5px clamp(3px, 1vw, 5px);
        font-size: 10px;
    }

    .hero-content h1 {
        font-size: 20px;
    }

    .hero-content p {
        font-size: 12px;
    }

    .hero-2 {
        padding-inline: 8px;
    }

    .feature-grid {
        gap: 7px;
    }

    .feature-card {
        padding-inline: 10px;
    }

    .portfolio-content {
        padding-top: 92px;
    }

    .portfolio-carousel {
        min-height: 340px;
    }

    .portfolio-card {
        min-height: 310px;
    }

    .support-content {
        padding-top: 72px;
    }

    .support-main {
        padding-bottom: 28px;
    }

    .support-card {
        min-height: 126px;
    }

    .support-icon {
        width: 42px;
        height: 42px;
    }

    .support-notes {
        margin-top: 14px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .page {
        scroll-behavior: auto;
    }

    .portfolio-card,
    .portfolio-arrow,
    .portfolio-dot,
    .support-card {
        transition-duration: 0.01ms;
    }
}