:root {
    --primary: #305496;
    --primary-light: rgba(48, 84, 150, 0.1);
    --primary-hover: rgba(48, 84, 150, 0.9);
    --neutral: #F5F7FA;
    --dark-0: #000;
    --dark: #1D2129;
    --gray-400: #9CA3AF;
    --gray-500: #6B7280;
    --gray-600: #4B5563;
    --white: #FFFFFF;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --radius: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: .625rem;
    --transition: all 0.3s ease;
}

p,
h1,
h2,
h3,
h4,
h5,
h6 {
    margin: 0;
}

/* * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
} */

html,
body {
    height: 100%;
    margin: 0;
    padding: 0;
    background-color: #fff;
    color: var(--dark);
    overflow: hidden;
    line-height: 1.5;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.main-container {
    /* 内容区高度 = 视口高度 - 导航栏高度（用百分比+calc） */
    height: calc(100% - 51px);
    /* 导航栏高度51px（含border） */
    margin-top: 51px;
    /* 避开固定导航栏 */
    overflow-y: auto;
    /* 内容区滚动 */
}

.portal {
    background-color: #fff;
}

.become-supplier {
    padding-top: 3.25rem;
}

.brand-story {
    padding: 3.125rem 0;
    padding-top: 3.25rem;
}

.contact-title {
    padding-top: 3.75rem;
}

.section-background {
    background-color: #f9f9f9;
}

/* 导航栏样式 */
header {
    position: fixed;
    top: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(4px);
    z-index: 100;
    width: 100%;
}

.header-logo {
    width: 10.75rem;
    height: 1.625rem;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 4rem;
}

.desktop-nav {
    display: none;
    gap: 2rem;
}

@media (min-width: 768px) {
    .desktop-nav {
        display: flex;
    }
}

.desktop-nav a {
    color: var(--gray-500);
    text-decoration: none;
    transition: var(--transition);
    padding-bottom: 0.25rem;
}

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

.desktop-nav a.active {
    color: var(--primary);
    font-weight: 500;
    border-bottom: 2px solid var(--primary);
}

.mobile-menu {
    display: none;
    background-color: var(--white);
}
.mobile-menu-border {
    border-top: 1px solid #E5E7EB;
    width: calc(100% - 32px);
    margin: 0 auto;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu a {
    display: block;
    padding: 0.75rem 0;
    color: var(--gray-500);
    text-decoration: none;
    transition: var(--transition);
}

.mobile-menu a:hover {
    color: var(--primary);
}

.mobile-menu a.active {
    color: var(--primary);
    font-weight: 500;
}

/* 主内容区样式 */
main {
    padding: 3rem 0 5rem;
}

.title-section {
    text-align: center;
    max-width: 36rem;
    margin: 0 auto;
    padding-top: 6rem;
}

.main-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 3.5rem;
}

.invention-main-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    margin: 0rem 0rem 1.25rem 0rem;
}

.sub-title {
    font-size: clamp(1.5rem, 2vw, 2.25rem);
    color: var(--dark-0);
    font-weight: 500;
}

.sub-title-tag {
    color: var(--primary);
    font-weight: 600;
    margin: 0 0.2rem;
}

.intro-text {
    color: var(--dark-0);
    font-size: clamp(.75rem, 2vw, 1.125rem);
    margin-top: 1rem;
}

.product-section {
    margin-bottom: 4rem;
}

.product-container {
    width: 90rem;
    margin: 0 auto;
    position: relative;
}

.product-display {
    border-radius: var(--radius-xl);
    overflow: hidden;
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.product-image {
    width: 50rem;
    height: 40rem;
    object-fit: contain;
    padding: 2rem;
}
.supplier-image {
    width: 3.5rem;
    height: 3.5rem;
}

@media (min-width: 768px) {
    .product-image {
        padding: 0rem 4rem;
    }
}

.feature-tag {
    position: absolute;
}

@media (min-width: 768px) {
    .feature-tag {
        width: 20rem;
    }
}

.feature-tag.top-left {
    top: 16%;
    left: 14%;
    transform: translateX(-25%);
}

@media (min-width: 768px) {
    .feature-tag.top-left {
        transform: translateX(-33%);
    }
}

@media (min-width: 1024px) {
    .feature-tag.top-left {
        transform: translateX(-50%);
    }
}

.feature-tag.top-right {
    top: 9%;
    right: 12%;
    transform: translateX(25%);
}

@media (min-width: 768px) {
    .feature-tag.top-right {
        transform: translateX(33%);
    }
}

@media (min-width: 1024px) {
    .feature-tag.top-right {
        transform: translateX(50%);
    }
}

.feature-tag.bottom-left {
    bottom: 30%;
    left: 14%;
    transform: translateX(-25%);
}

@media (min-width: 768px) {
    .feature-tag.bottom-left {
        transform: translateX(-33%);
    }
}

@media (min-width: 1024px) {
    .feature-tag.bottom-left {
        transform: translateX(-50%);
    }
}

.feature-tag.bottom-right {
    bottom: 18%;
    right: 10%;
    transform: translateX(25%);
}

@media (min-width: 768px) {
    .feature-tag.bottom-right {
        transform: translateX(33%);
    }
}

@media (min-width: 1024px) {
    .feature-tag.bottom-right {
        transform: translateX(50%);
    }
}

.feature-title {
    font-size: 2rem;
    font-weight: 500;
    margin-bottom: 0.25rem;
}

.feature-desc {
    font-size: 1.125rem;
    color: var(--gray-600);
}

.cta-button {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    background-color: var(--primary);
    color: var(--white);
    border: none;
    border-radius: 2.5rem;
    padding: 0.875rem 2rem;
    font-weight: 500;
    font-size: 1.25rem;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow-lg);
    margin: 0 auto;
}

.cta-button:hover {
    background-color: var(--primary-hover);
    box-shadow: 0 10px 15px rgba(48, 84, 150, 0.2);
}

.supplier-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    max-width: 75rem;
    margin: 0 auto;
    margin-bottom: 1rem;
}

@media (min-width: 768px) {
    .supplier-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.supplier-card {
    background-color: var(--white);
    border-radius: var(--radius-xl);
    padding: 2rem 1.5rem 1rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    /* opacity: 0; */
    transform: translateY(1rem);
    display: flex;
}

.supplier-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.supplier-card:hover {
    transform: translateY(-1.25rem);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.supplier-icon-container {
    margin-bottom: 1rem;
    margin-right: 2.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.supplier-icon {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 0.375rem;
}

.supplier-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    width: 5rem;
}

.supplier-card-text {
    font-size: 14px;
    color: #000000;
    line-height: 24px;
    font-weight: 400;
    color: var(--dark-0);
    margin-bottom: 1rem;
}

/* 页脚样式 */
footer {
    background-color: var(--primary);
    color: var(--white);
    padding: 0.5rem 0;
}

.footer-bottom {
    text-align: center;
    font-size: 0.75rem;
}


.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section-title {
    text-align: left;
    font-size: 3.8rem;
    margin-bottom: 3rem;
    color: #333;
    padding-top: 3rem;
    margin-top: 0rem;
}

.story-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    height: 732px;
}

.birth-story,
.steips-model {
    background: white;
    padding: 32px 48px;
    border-radius: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.birth-story h3 {
    font-size: 2rem;
    margin-bottom: 1.2rem;
}

.steips-model h3 {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 1.2rem;
}

.birth-story p {
    font-size: 16px;
    color: #000000;
    letter-spacing: 0;
    line-height: 28px;
    font-weight: 400;
}
.birth-story-margin {
    margin-bottom: 2rem;
}

.quote-container {
    max-width: 800px;
    margin: 2rem auto;
    padding: 1.25rem 1rem;
    border: 1px dashed #ccc;
    border-radius: 4px;
}

.quote-text {
    font-size: 1.2rem;
    line-height: 1.6;
    color: #000;
}

.quote-author {
    font-size: 1rem;
    font-weight: 600 !important;
    color: #000;
    text-align: left;
}

.founder {
    text-align: right;
    color: #888;
}

.steips-diagram {
    position: relative;
    margin: 0 auto 3.625rem;
    width: 20rem;
    height: 19.5rem;
}

.steips-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.center-circle {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: #3498db;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    text-align: center;
}

.steips-item {
    position: absolute;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.steips-item img {
    width: 50px;
    height: 50px;
    margin-bottom: 8px;
}

.factor-name {
    font-size: 14px;
    color: #333;
}

/* 六要素位置布局 */
.s-factor {
    top: 0;
    left: 50%;
    transform: translateX(-50%);
}

.t-factor {
    top: 30%;
    right: 10%;
}

.e-factor {
    bottom: 30%;
    right: 10%;
}

.p-factor {
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
}

.i-factor {
    bottom: 30%;
    left: 10%;
}

.s2-factor {
    top: 30%;
    left: 10%;
}

.steips-desc {
    font-size: 16px;
    line-height: 16px;
    font-weight: 400;
    margin-bottom: 22px;
}

.steips-desc-sub1 {
    font-size: 14px;
    color: #000000;
    line-height: 28px;
    font-weight: 400;
}

.steips-sub1-span {
    color: var(--primary);
}

@media (max-width: 768px) {
    .story-content {
        grid-template-columns: 1fr;
    }

    .steips-item img {
        width: 40px;
        height: 40px;
    }

    .factor-name {
        font-size: 12px;
    }
}

.section-intro {
    font-size: 18px;
    line-height: 28px;
    font-weight: 400;
    margin-bottom: 2.1rem;
}

.timeline {
    max-width: 900px;
    margin: 0 auto;
    position: relative;
}

.timeline-item {
    position: relative;
    display: flex;
    align-items: flex-start;
    position: relative;
}

.timeline-item:nth-child(odd) {
    flex-direction: row-reverse;
    justify-content: flex-end;
    width: calc(50% + 55px);
}

.timeline-item:not(:last-child)::after {
    content: '';
    position: absolute;
    top: 0;
    transform: translateX(-50%);
    height: 100%;
    border: 1px dashed var(--primary);
    transform: scalex(0.5);
    pointer-events: none;
}

/* .timeline-item:not(:first-child)::before {
    content: '';
    position: absolute;
    top: 0;
    transform: translateX(-50%);
    height: 100%;
    border: 1px dashed var(--primary);
    transform: scalex(0.5);
    pointer-events: none;
} */

/* .timeline-item::before {
    left: 50px;
} */

.timeline-item:nth-child(odd)::after {
    left: calc(100% - 50px);
}

.timeline-item:nth-child(even)::after {
    left: calc(50% - 25px);
}

.timeline-item:nth-child(even) {
    justify-content: flex-end;
    width: calc(100% + 55px);
}

.timeline-img-container {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    overflow: hidden;
    position: relative;
    z-index: 1;
    background-color: #fff;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.2);
}

.timeline-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.timeline-content {
    flex: 1;
    background-color: #fff;
    padding: 16px;
    border-radius: var(--radius-xl);
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.1);
    position: relative;
    margin: 0 20px;
    max-width: 400px;
}

.timeline-content h2 {
    font-size: 24px;
    color: #000000;
    letter-spacing: 0;
    text-align: justify;
    font-weight: 500;
}

.timeline-content .date {
    padding: 4px 0px;
    font-size: 14px;
    color: #666666;
    letter-spacing: 0;
    text-align: justify;
    font-weight: 400;
    border-bottom: 1px dashed #f1f1f1;
    margin-bottom: 16px;
}

.timeline-content p {

    font-size: 14px;
    color: #000000;
    letter-spacing: 0;
    text-align: justify;
    line-height: 24px;
    font-weight: 400;
}


.timeline-item:nth-child(odd) .timeline-content {
    margin: 0 20px 0 0;
}

.timeline-item:nth-child(even) .timeline-content {
    margin: 0 0 0 20px;
}

.timeline-content::before {
    content: '';
    position: absolute;
    top: 30px;
    width: 0;
    height: 0;
    border-style: solid;
}


.timeline-item:nth-child(odd) .timeline-content::before {
    right: -6px;
    border-width: 12px 0 12px 10px;
    border-color: transparent transparent transparent #fff;
}

.timeline-item:nth-child(even) .timeline-content::before {
    left: -6px;
    border-width: 12px 12px 12px 0;
    border-color: transparent #fff transparent transparent;
}

@media (max-width: 768px) {
    .timeline-content > h2 {
        font-size: 18px;
        color: #000000;
        line-height: 18px;
        font-weight: 500;
    }
    .timeline-content .date {
        font-size: 12px;
        color: #666666;
        line-height: 12px;
        font-weight: 400;
    }

    .timeline-content p {
        font-size: 12px;
        color: #000000;
        line-height: 20px;
        font-weight: 400;
    }
    
    .timeline-img-container {
        width: 3.75rem;
        height: 3.75rem;
    }

    .timeline-item:nth-child(odd) {
        flex-direction: row;
        justify-content: flex-end;
        width: 100%;
    }

    .timeline-item:nth-child(even) {
        flex-direction: row;
        justify-content: flex-end;
        width: 100%;
    }

    .timeline-item:nth-child(odd)::after {
        left: 1.875rem;
    }

    .timeline-item:nth-child(even)::after {
        left: 1.875rem;
    }

    .timeline-item:nth-child(odd) .timeline-content::before {
        left: -0.375px;
        border-width: 0.75rem .75rem .75rem 0;
        border-color: transparent #fff transparent transparent;
    }
    
    .timeline-item:nth-child(odd):not(:last-child) .timeline-content {
        margin: -2.5rem 0px 3.125rem 20px; 
    }

    .timeline-item:nth-child(odd):last-child .timeline-content {
        margin: -2.5rem 0px 0rem 20px; 
    }
    .timeline-item:nth-child(even) .timeline-content {
         margin: -2.5rem 0px 3.125rem 20px; 
    }
    .timeline-content::before {
        top: 50px;
    }
    .timeline-item:nth-child(odd) .timeline-content::before {
        left: -6px;
    }
    
}


.contact-grid {
    display: grid;
    grid-template-columns: 1fr;
    margin: 0 auto;
    padding-bottom: 4.5rem;
}

.contact-card {
    background-color: var(--white);
    border-radius: var(--radius-xl);
    padding: 2.5rem 1.5rem 1.25rem;
}

.contact-card p {
    margin-bottom: 1.25rem;
}

.contact-title {
    font-size: 2.25rem;
    margin-bottom: 1.5rem;
    color: var(--dark-0);
    font-weight: 500;
}

.contact-card-email {
    color: var(--primary);
    font-weight: 600;
}

@media (max-width: 768px) {
    .portal {
        margin-bottom: 1.5625rem;
    }
    .timeline {
        width: 360px;
    }
    .main-title {
        font-size: 2rem;
        color: #000000;
        font-weight: 600;
        margin-bottom: 2rem;
    }
    .intro-text{
        padding: 0 2rem;
    }
    .cta-button {
        font-size: 1rem;
        padding: .5rem 1.125rem .625rem;
        margin-top: 3.125rem;
    }
    .product-section {
        margin-bottom: 1.5rem;
    }
    .section-title {
        font-size: 2rem;
        color: #000000;
        font-weight: 600;
        margin-bottom: 1.25rem;
    }
    
    .section-intro {
        font-size: .75rem;
        line-height: 1.25rem;
        color: #000000;
        font-weight: 400;
        margin-bottom: 1.25rem;
    }
    .mission-time > .container >.section-intro {
        margin-bottom: 3.75rem;
    }
    .section-background {
        padding: 1.5625rem 1rem;
    }
    .birth-story,
    .steips-model {
        padding: 1.25rem;
        width: calc(100% - 2.5rem);
        border-radius: .625rem;
    }
    .birth-story > h3 {
        font-size: 1.5rem;
        color: #000000;
        font-weight: 500;
    }
    .birth-story p {
        font-size: 12px;
        color: #000000;
        line-height: 1rem;
        font-weight: 400;
    }
    .birth-story-margin {
        margin-bottom: 1.25rem;
    }
    .steips-diagram {
        margin-bottom: 30px;
    }
    .steips-desc,.steips-desc-sub1 {
        font-size: 12px;
        color: #000000;
        line-height: 20px;
        font-weight: 400;
    }
    .steips-desc {
        margin-bottom: 16px;
    }
    .supplier-card {
        padding: 1.5rem 1.25rem .5rem;
        transform: none;
    }
    .contact-card {
        padding: 1.25rem;
    }
    .contact-card p {
        font-size: 14px;
        color: #000000;
        line-height: 22px;
        font-weight: 400;
    }
    .contact-title {
        padding-top: 2rem;
        margin-bottom: 1rem;
    }
    .contact-grid{
        padding-bottom: 3.125rem;
    }
    .story-content {
        gap: 10px;
    }
}

    @media (max-width: 768px) {
        .header-container {
            height: 2.875rem;
        }

        .header-logo {
            width: 6.25rem;
            height: 1rem;
            padding-left: 1rem;
        }

        .container {
            padding: 0rem;
        }

        .product-container {
            width: 25rem;
            height: 35rem;
        }

        .title-section {
            padding-top: 2.5rem;
            margin-bottom: 3.25rem;
        }

        .section-title {
            padding-top: 0rem;
        }

        .product-display {
            width: 20.5rem;
            margin: 0 auto;
            position: relative;
            height: 27rem;
        }

        .product-image {
            width: 19rem;
            height: 20.5rem;
            margin-top: 3rem;
            padding: 0rem;
        }

        .feature-tag {
            padding: 0;
            position: absolute;
        }

        .feature-tag.top-left {
            top: 0%;
            left: 2%;
            transform: translateX(0%);
        }

        .feature-tag.top-right>.feature-title,
        .feature-tag.bottom-right>.feature-title {
            text-align: right;
        }

        .feature-tag.top-right {
            top: 10%;
            right: 2%;
            transform: translateX(0%);
        }

        .feature-tag.bottom-left {
            bottom: -5%;
            left: 4%;
            transform: translateX(0%);
        }

        .feature-tag.bottom-right {
            bottom: 6%;
            right: 2%;
            transform: translateX(0%);
        }

        .feature-title {
            font-size: 1.125rem;
            color: #000000;
            text-align: justify;
            font-weight: 500;
        }

        .feature-desc {
            font-size: .75rem;
            color: #666666;
            text-align: justify;
            font-weight: 400;
        }

        .advantage-card-image {
            width: 2.5rem;
            height: 2.5rem;
        }

        .card-title {
            font-size: 18px;
            color: #000000;
            font-weight: 500;
        }

        .advantage-card-check {
            width: 1rem;
            height: 1rem;
        }

        .advantage-card-title {
            font-size: 14px;
            color: #000000;
            font-weight: 500;
        }

        .advantage-card-desc {
            font-size: 12px;
            color: #000000;
            font-weight: 400;
            text-align: left;
        }

        .main-container {
            overflow-x: hidden;
        }

        footer {
            width: calc(100% + 4rem);
            margin-left: -2rem;
        }
        .brand-story {
            padding-top: 3.125rem;
        }
        .supplier-grid {
            gap: 10px;
            margin-bottom: 0;
        }
    }

    .menu-btn {
        display: block;
        background: none;
        border: none;
        cursor: pointer;
        margin-right: 1rem;
    }

    .menu-btn>img {
        width: 1rem;
        height: 1rem;
    }

    @media (min-width: 768px) {
        .menu-btn {
            display: none;
        }
    }
.mobile-arrow {
    float: right;
    width: 12px;
    height: 18px;
}
.footer-bottom-a {
    text-decoration: none;
    color: #fff;
}
.footer-bottom-content {
    display: flex;
    text-align: center;
    align-items: center;
    justify-content: center;
}
.footer-bottom-right {
    display: flex;
    text-align: center;
    align-items: center;
    justify-content: center;
}

@media (max-width: 768px) {
    .footer-bottom-content {
        flex-direction: column;
    }
}