/* ===== 基础重置 ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --color-primary: #5e6ad2;
    --color-primary-light: #7c85e0;
    --color-bg: #ffffff;
    --color-bg-alt: #f5f5f7;
    --color-bg-dark: #1d1d1f;
    --color-text: #1d1d1f;
    --color-text-secondary: #6e6e73;
    --color-text-light: #999;
    --color-border: #e5e5e7;
    --nav-height: 64px;
    --section-padding: 72px;
    --container-width: 1200px;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

img {
    max-width: 100%;
    display: block;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.72);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    transition: box-shadow 0.3s ease, background 0.3s ease;
}

.navbar.scrolled {
    box-shadow: 0 1px 0 var(--color-border);
    background: rgba(255, 255, 255, 0.92);
}

.nav-container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    font-size: 1.1rem;
    z-index: 1001;
    white-space: nowrap;
    overflow: hidden;
    min-width: 0;
}

.nav-logo-img {
    width: 32px;
    height: 32px;
    border-radius: 8px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 32px;
}

.nav-links a {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    transition: color 0.2s;
    font-weight: 500;
}

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

/* 汉堡菜单按钮 */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 1001;
}

.nav-toggle span {
    width: 20px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: transform 0.3s, opacity 0.3s;
}

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

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

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

/* ===== Hero 区域 ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 24px;
    background: linear-gradient(180deg, #f0f2ff 0%, #ffffff 100%);
    gap: 60px;
    max-width: 100vw;
}

.hero-content {
    flex: 1;
    max-width: 540px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.hero-title-gradient {
    background: linear-gradient(135deg, var(--color-primary) 0%, #8b5cf6 50%, #ec4899 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--color-text-secondary);
    font-weight: 500;
    margin-bottom: 20px;
    letter-spacing: 0.15em;
}

.hero-desc {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: 36px;
}

.hero-actions {
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--color-primary-light);
    transform: translateY(-1px);
    box-shadow: 0 8px 24px rgba(94, 106, 210, 0.3);
}

/* 手机模型 */
.hero-visual {
    flex-shrink: 0;
}

.hero-phone-mockup {
    width: 280px;
    height: 560px;
    background: #1d1d1f;
    border-radius: 40px;
    padding: 12px;
    box-shadow: 0 40px 80px rgba(0, 0, 0, 0.15), 0 0 0 1px rgba(0, 0, 0, 0.05);
    overflow: hidden;
    position: relative;
}

.hero-phone-mockup::before {
    content: '';
    position: absolute;
    top: 12px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 28px;
    background: #1d1d1f;
    border-radius: 0 0 16px 16px;
    z-index: 2;
}

.hero-phone-screen {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 28px;
}

/* ===== 通用 Section 样式 ===== */
.section {
    padding: var(--section-padding) 24px;
}

.section-container {
    max-width: var(--container-width);
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-tag {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    margin-bottom: 16px;
    padding: 6px 16px;
    background: rgba(94, 106, 210, 0.08);
    border-radius: 20px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    letter-spacing: -0.01em;
    color: var(--color-text);
}

.section-desc {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.7;
}

.about-intro {
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: 0.04em;
    max-width: 100%;
}

.company-name {
    font-weight: 800;
    font-style: italic;
    color: var(--color-primary);
}

/* ===== 公司介绍 ===== */
.section-about {
    background: var(--color-bg-alt);
    padding-top: calc(var(--nav-height) + var(--section-padding));
}

.about-narrative {
    max-width: 960px;
    margin: 0 auto 40px;
    text-align: center;
}

.narrative-content p {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: 0;
}

.narrative-highlight {
    font-size: 1.35rem !important;
    font-weight: 700;
    color: var(--color-text) !important;
    margin: 8px 0 !important;
    position: relative;
    display: inline-block;
}

.about-values-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.about-value-card {
    background: #fff;
    border-radius: 16px;
    padding: 24px 20px;
    text-align: center;
    border: 1px solid var(--color-border);
    transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}

.about-value-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.06);
    border-color: var(--color-border);
    background: #fff;
}

.about-value-icon {
    width: 36px;
    height: 36px;
    margin: 0 auto 12px;
    color: var(--color-primary);
}

.about-value-icon svg {
    width: 100%;
    height: 100%;
}

.about-value-label {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 6px;
    color: var(--color-text);
}

.about-value-text {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ===== 产品大模块 ===== */
.section-product {
    background: var(--color-bg);
}

.hero-merged {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 60px;
    background: linear-gradient(180deg, #f0f2ff 0%, #ffffff 100%);
    border-radius: 24px;
    margin-bottom: 48px;
    padding: 48px 40px;
}

.product-sub-header {
    text-align: center;
    margin: 48px 0 32px;
}

.product-sub-header .section-title {
    font-size: 1.8rem;
}

@media (max-width: 1024px) {
    .hero-merged {
        flex-direction: column;
        text-align: center;
        padding: 36px 24px;
        gap: 36px;
    }

    .hero-merged .hero-actions {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .hero-merged {
        padding: 28px 20px;
        gap: 28px;
        margin-bottom: 32px;
    }

    .product-sub-header {
        margin: 32px 0 24px;
    }

    .product-sub-header .section-title {
        font-size: 1.5rem;
    }
}

.hero-title {
    display: flex;
    align-items: center;
    gap: 16px;
}

.product-app-icon {
    width: 72px;
    height: 72px;
    border-radius: 18px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
    flex-shrink: 0;
}

@media (max-width: 1024px) {
    .hero-title {
        justify-content: center;
        flex-wrap: wrap;
    }

    .hero-merged .hero-content {
        max-width: 100%;
    }
}

@media (max-width: 768px) {
    .product-app-icon {
        width: 56px;
        height: 56px;
        border-radius: 14px;
    }
}

/* ===== 功能特色 + 截图 ===== */
.feature-showcase-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 48px;
}

.feature-showcase-item {
    text-align: center;
}

.feature-showcase-item h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 4px;
    color: var(--color-text);
}

.feature-showcase-item p {
    font-size: 0.85rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: 12px;
}

.feature-showcase-item img {
    width: 75%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 6px 24px rgba(0, 0, 0, 0.08);
    margin: 0 auto;
}

@media (max-width: 768px) {
    .feature-showcase-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
        margin-top: 32px;
    }

    .feature-showcase-item img {
        width: 90%;
    }
}

@media (max-width: 480px) {
    .feature-showcase-grid {
        gap: 12px;
    }

    .feature-showcase-item h3 {
        font-size: 0.9rem;
    }
}

/* ===== 产品介绍 ===== */
.section-app {
    background: var(--color-bg-alt);
}

.app-card {
    display: flex;
    align-items: center;
    gap: 48px;
    background: #fff;
    border-radius: 24px;
    padding: 48px;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
    border: 1px solid var(--color-border);
    max-width: 800px;
    margin: 0 auto;
}

.app-card-icon {
    flex-shrink: 0;
}

.app-icon-img {
    width: 100px;
    height: 100px;
    border-radius: 22px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

.app-card-info {
    flex: 1;
}

.app-card-name {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.app-card-tagline {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    margin-bottom: 12px;
}

.app-card-badges {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.badge {
    display: inline-block;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 6px;
    background: rgba(94, 106, 210, 0.08);
    color: var(--color-primary);
}

.app-card-desc {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: 20px;
}

.app-download-hint {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
    color: var(--color-text);
    font-weight: 500;
    padding: 12px 16px;
    background: var(--color-bg-alt);
    border-radius: 12px;
}

.btn-download {
    gap: 8px;
    margin-bottom: 12px;
}

.btn-download svg {
    flex-shrink: 0;
}

.download-icon {
    font-size: 1.2rem;
}

/* ===== 功能特色 ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--color-bg-alt);
    border-radius: 20px;
    padding: 36px 28px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid transparent;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.06);
    border-color: var(--color-border);
    background: #fff;
}

.feature-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 20px;
    color: var(--color-primary);
}

.feature-icon svg {
    width: 100%;
    height: 100%;
}

.feature-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.feature-desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ===== 产品截图 ===== */
.section-screenshots {
    background: var(--color-bg-alt);
}

.screenshots-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    max-width: 800px;
    margin: 0 auto;
}

.screenshot-item {
    text-align: center;
}

.screenshot-item img {
    width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s, box-shadow 0.3s;
    background: #fff;
}

.screenshot-item img:hover {
    transform: translateY(-6px) scale(1.02);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.12);
}

.screenshot-caption {
    margin-top: 14px;
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    font-weight: 500;
}

/* ===== 联系我们 ===== */
.section-contact {
    background: linear-gradient(180deg, #ffffff 0%, #f0f2ff 100%);
}

.contact-card {
    text-align: center;
    max-width: 480px;
    margin: 0 auto;
    padding: 48px;
    background: #fff;
    border-radius: 24px;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
    border: 1px solid var(--color-border);
}

.contact-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 24px;
    color: var(--color-primary);
    background: rgba(94, 106, 210, 0.08);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 14px;
}

.contact-icon svg {
    width: 100%;
    height: 100%;
}

.contact-email {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-primary);
    transition: opacity 0.2s;
}

.contact-email:hover {
    opacity: 0.7;
}

/* ===== 页脚 ===== */
.footer {
    background: var(--color-bg-dark);
    color: rgba(255, 255, 255, 0.6);
    padding: 48px 24px 32px;
}

.footer-container {
    max-width: var(--container-width);
    margin: 0 auto;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 16px;
}

.footer-logo {
    width: 28px;
    height: 28px;
    border-radius: 6px;
}

.footer-brand-name {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.85);
    font-weight: 500;
}

.footer-links {
    margin-bottom: 24px;
}

.footer-links a {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.5);
    transition: color 0.2s;
}

.footer-links a:hover {
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom {
    font-size: 0.8rem;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.footer-bottom a {
    color: rgba(255, 255, 255, 0.4);
    transition: color 0.2s;
}

.footer-bottom a:hover {
    color: rgba(255, 255, 255, 0.7);
}

.footer-divider {
    color: rgba(255, 255, 255, 0.2);
}

.footer-copyright {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.3);
}

/* ===== 滚动动画 ===== */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

.about-value-card.animate-on-scroll { transition-delay: 0s; }
.about-value-card.animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.about-value-card.animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }
.about-value-card.animate-on-scroll:nth-child(4) { transition-delay: 0.3s; }

.feature-card.animate-on-scroll { transition-delay: 0s; }
.feature-card.animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.feature-card.animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }
.feature-card.animate-on-scroll:nth-child(4) { transition-delay: 0.3s; }

.screenshot-item.animate-on-scroll { transition-delay: 0s; }
.screenshot-item.animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.screenshot-item.animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }
.screenshot-item.animate-on-scroll:nth-child(4) { transition-delay: 0.3s; }

/* ===== 响应式 — 平板 ===== */
@media (max-width: 1024px) {
    :root {
        --section-padding: 56px;
    }

    .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 40px;
        min-height: auto;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-phone-mockup {
        width: 220px;
        height: 440px;
        border-radius: 32px;
    }

    .about-values-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .screenshots-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .app-card {
        flex-direction: column;
        text-align: center;
        padding: 36px;
    }
}

/* ===== 响应式 — 手机 ===== */
@media (max-width: 768px) {
    :root {
        --section-padding: 48px;
        --nav-height: 56px;
    }

    /* 导航 */
    .nav-toggle {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        z-index: 999;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 32px;
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.3s;
    }

    .nav-links.active {
        opacity: 1;
        pointer-events: all;
    }

    .nav-links li {
        list-style: none;
    }

    .nav-links a {
        font-size: 1.4rem;
        font-weight: 600;
        color: var(--color-text);
    }

    /* Nav */
    .nav-logo {
        font-size: 0.85rem;
    }

    .nav-logo-text {
        overflow: hidden;
        text-overflow: ellipsis;
    }

    /* Hero */
    .hero-title {
        font-size: 2.5rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .hero-desc {
        font-size: 1rem;
    }

    .hero-phone-mockup {
        width: 200px;
        height: 400px;
        border-radius: 28px;
        padding: 10px;
    }

    .hero-phone-mockup::before {
        width: 80px;
        height: 22px;
        top: 10px;
    }

    /* Section */
    .section-title {
        font-size: 1.8rem;
    }

    .section-desc {
        font-size: 1rem;
    }

    .section-header {
        margin-bottom: 40px;
    }

    /* About */
    .about-values-grid {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }

    .about-intro {
        font-size: 1.1rem;
    }

    .about-narrative {
        margin-bottom: 40px;
    }

    .narrative-content p {
        font-size: 1rem;
    }

    .narrative-highlight {
        font-size: 1.15rem !important;
    }

    .app-card-badges {
        justify-content: center;
    }

    .app-download-hint {
        justify-content: center;
    }

    /* Features */
    .features-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .feature-card {
        padding: 28px 24px;
        text-align: left;
        display: flex;
        gap: 20px;
        align-items: flex-start;
    }

    .feature-icon {
        margin: 0;
        flex-shrink: 0;
        width: 40px;
        height: 40px;
    }

    .feature-card .feature-title,
    .feature-card .feature-desc {
        text-align: left;
    }

    /* Screenshots */
    .screenshots-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    /* App Card */
    .app-card {
        padding: 28px;
        gap: 24px;
    }

    .app-icon-img {
        width: 80px;
        height: 80px;
    }

    /* Contact */
    .contact-card {
        padding: 32px 24px;
    }

    .contact-email {
        font-size: 1.05rem;
    }

    /* Footer */
    .footer {
        padding: 28px 24px 20px;
    }
}

/* ===== 响应式 — 小屏手机 ===== */
@media (max-width: 480px) {
    .nav-logo {
        font-size: 0.75rem;
    }

    .hero-title {
        font-size: 2rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    .hero-phone-mockup {
        width: 180px;
        height: 360px;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .screenshots-grid {
        grid-template-columns: 1fr 1fr;
        gap: 12px;
    }

    .about-intro {
        font-size: 0.95rem;
    }

    .section-title {
        font-size: 1.3rem;
    }

    .contact-card {
        padding: 24px 16px;
    }

    .contact-email {
        font-size: 0.9rem;
        word-break: break-all;
    }

    .app-download-hint {
        flex-direction: column;
        text-align: center;
        gap: 4px;
    }

    .feature-showcase-item h3 {
        font-size: 0.8rem;
    }

    .feature-showcase-item p {
        font-size: 0.75rem;
    }

    .footer-brand-name {
        font-size: 0.8rem;
    }

    .footer-bottom {
        flex-direction: column;
        gap: 6px;
    }

    .footer-divider {
        display: none;
    }
}

/* ===== 滚动条 ===== */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: #aaa;
}

/* ===== 选择高亮 ===== */
::selection {
    background: rgba(94, 106, 210, 0.15);
    color: var(--color-text);
}