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

:root {
    --blue: #2563eb;
    --blue-dark: #1d4ed8;
    --blue-soft: #eff6ff;
    --ink: #0f172a;
    --muted: #526076;
    --line: #e2e8f0;
    --surface: #ffffff;
    --background: #f8fafc;
    --amber: #92400e;
    --amber-bg: #fffbeb;
    --radius-lg: 28px;
    --radius-md: 18px;
    --shadow: 0 20px 60px rgba(15, 23, 42, 0.08);
}

html {
    scroll-behavior: smooth;
}

body {
    min-width: 320px;
    background: var(--background);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", sans-serif;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
}

h1, h2, h3, blockquote, .section-heading p {
    text-wrap: balance;
}

p, li {
    text-wrap: pretty;
}

a, button {
    -webkit-tap-highlight-color: transparent;
}

svg {
    fill: none;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 1.8;
}

.site-header {
    position: absolute;
    z-index: 10;
    top: 0;
    width: 100%;
}

.nav-shell {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: min(1120px, calc(100% - 40px));
    height: 72px;
    margin: 0 auto;
}

.brand,
.back-link {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    color: var(--ink);
    font-weight: 650;
    text-decoration: none;
}

.brand {
    gap: 10px;
    font-size: 1rem;
}

.brand-mark {
    width: 36px;
    height: 36px;
    border-radius: 11px;
    object-fit: cover;
    box-shadow: 0 5px 16px rgba(37, 99, 235, 0.22);
}

.back-link {
    gap: 4px;
    color: var(--muted);
    font-size: 0.9rem;
    transition: color 180ms ease;
}

.back-link svg {
    width: 18px;
    height: 18px;
}

.back-link:hover {
    color: var(--blue);
}

.hero {
    position: relative;
    display: grid;
    min-height: 680px;
    padding: 150px 24px 110px;
    overflow: hidden;
    place-items: center;
    background: #fff;
    text-align: center;
}

.hero::before,
.hero::after,
.hero-glow {
    position: absolute;
    border-radius: 999px;
    content: "";
    pointer-events: none;
}

.hero::before {
    top: 12%;
    left: -100px;
    width: 300px;
    height: 300px;
    background: rgba(37, 99, 235, 0.08);
    filter: blur(4px);
}

.hero::after {
    right: -80px;
    bottom: 8%;
    width: 240px;
    height: 240px;
    background: rgba(14, 165, 233, 0.08);
}

.hero-glow {
    top: 45%;
    left: 50%;
    width: 720px;
    height: 420px;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.09), transparent 68%);
    transform: translate(-50%, -50%);
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 760px;
}

.eyebrow,
.section-kicker,
.step-label {
    color: var(--blue);
    font-size: 0.78rem;
    font-weight: 750;
    letter-spacing: 0.1em;
}

.hero h1 {
    margin-top: 20px;
    font-size: clamp(3.2rem, 8vw, 6.5rem);
    font-weight: 760;
    letter-spacing: -0.07em;
    line-height: 0.95;
}

.hero h1 span {
    background: linear-gradient(90deg, var(--blue-dark), #0ea5e9);
    background-clip: text;
    color: transparent;
    -webkit-background-clip: text;
}

.hero p {
    max-width: 620px;
    margin: 30px auto 0;
    color: var(--muted);
    font-size: clamp(1rem, 2vw, 1.2rem);
}

.primary-button,
.action-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 52px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 650;
    text-decoration: none;
    transition: background-color 180ms ease, box-shadow 180ms ease;
}

.primary-button {
    gap: 10px;
    margin-top: 38px;
    padding: 0 26px;
    box-shadow: 0 10px 28px rgba(37, 99, 235, 0.24);
}

.primary-button svg,
.action-button svg {
    width: 18px;
    height: 18px;
}

.primary-button:hover,
.action-button:hover {
    background: var(--blue-dark);
    box-shadow: 0 12px 30px rgba(37, 99, 235, 0.3);
}

.product-intro,
.design-story {
    width: min(1100px, calc(100% - 40px));
    margin: 0 auto;
}

.product-intro {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
    align-items: center;
    gap: clamp(40px, 8vw, 100px);
    padding: 120px 0;
}

.intro-copy h2 {
    margin-top: 12px;
    font-size: clamp(2.8rem, 6vw, 5.5rem);
    letter-spacing: -0.065em;
    line-height: 1;
}

.intro-copy > p {
    max-width: 600px;
    margin-top: 26px;
    color: var(--muted);
    font-size: 1.05rem;
}

.feature-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 28px;
}

.feature-pills span {
    padding: 8px 14px;
    border: 1px solid #bfdbfe;
    border-radius: 999px;
    background: var(--blue-soft);
    color: var(--blue-dark);
    font-size: 0.82rem;
    font-weight: 700;
}

.intro-visual {
    position: relative;
    padding: 20px;
}

.intro-visual::before {
    position: absolute;
    inset: 8% -4% -2% 8%;
    border-radius: 40%;
    background: radial-gradient(circle, rgba(14, 165, 233, 0.19), rgba(37, 99, 235, 0.05) 60%, transparent 72%);
    content: "";
    filter: blur(16px);
}

.intro-visual img {
    position: relative;
    display: block;
    width: 100%;
    height: auto;
    border-radius: 28%;
    box-shadow: 0 30px 80px rgba(37, 99, 235, 0.24);
}

.design-story {
    padding: 110px 0;
    border-top: 1px solid var(--line);
}

.logo-elements {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    max-width: 860px;
    margin: 0 auto;
}

.element-card {
    padding: 34px 24px 26px;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    background: #fff;
    box-shadow: var(--shadow);
    text-align: center;
}

.element-icon {
    display: grid;
    width: 76px;
    height: 76px;
    margin: 0 auto;
    place-items: center;
    border-radius: 24px;
    background: linear-gradient(135deg, #3b82f6, var(--blue-dark));
    color: #fff;
    box-shadow: 0 12px 28px rgba(37, 99, 235, 0.25);
}

.element-icon svg {
    width: 36px;
    height: 36px;
}

.element-card figcaption {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-top: 20px;
}

.element-card figcaption span {
    color: #64748b;
    font-size: 0.8rem;
}

.element-card figcaption strong {
    font-size: 1.05rem;
}

.design-story blockquote {
    max-width: 800px;
    margin: 58px auto 0;
    color: var(--ink);
    font-size: clamp(1.8rem, 4.5vw, 3.6rem);
    font-weight: 750;
    letter-spacing: -0.05em;
    line-height: 1.2;
    text-align: center;
}

.story-note {
    max-width: 680px;
    margin: 22px auto 0;
    color: var(--muted);
    text-align: center;
}

.tutorial {
    width: min(980px, calc(100% - 40px));
    margin: 0 auto;
    padding: 110px 0 90px;
}

.section-heading {
    margin-bottom: 48px;
    text-align: center;
}

.section-heading h2 {
    margin-top: 8px;
    font-size: clamp(2rem, 5vw, 3.2rem);
    letter-spacing: -0.045em;
    line-height: 1.15;
}

.section-heading p {
    margin-top: 14px;
    color: var(--muted);
}

.steps-list {
    display: grid;
    gap: 24px;
}

.step-card {
    position: relative;
    overflow: hidden;
    border: 1px solid rgba(226, 232, 240, 0.9);
    border-radius: var(--radius-lg);
    background: var(--surface);
    box-shadow: var(--shadow);
}

.step-number {
    position: absolute;
    top: -26px;
    right: 24px;
    color: #f1f5f9;
    font-size: 8rem;
    font-weight: 800;
    letter-spacing: -0.08em;
    line-height: 1;
    user-select: none;
}

.step-body {
    position: relative;
    display: grid;
    grid-template-columns: 60px minmax(0, 1fr);
    gap: 26px;
    padding: 44px;
}

.step-icon {
    display: grid;
    width: 60px;
    height: 60px;
    place-items: center;
    border-radius: 18px;
    background: var(--blue-soft);
    color: var(--blue);
}

.step-icon svg {
    width: 28px;
    height: 28px;
}

.step-copy {
    min-width: 0;
}

.step-copy h3 {
    margin: 4px 0 12px;
    font-size: clamp(1.55rem, 3vw, 2rem);
    letter-spacing: -0.035em;
    line-height: 1.2;
}

.step-copy > p:not(.step-label, .link-caption) {
    max-width: 690px;
    color: var(--muted);
}

.notice {
    display: grid;
    grid-template-columns: 24px minmax(0, 1fr);
    gap: 12px;
    margin-top: 24px;
    padding: 18px;
    border: 1px solid #fde68a;
    border-radius: 15px;
    background: var(--amber-bg);
    color: var(--amber);
}

.notice > svg {
    width: 22px;
    height: 22px;
    margin-top: 1px;
}

.notice strong {
    font-size: 0.95rem;
}

.notice p {
    margin-top: 4px;
    font-size: 0.9rem;
    line-height: 1.65;
}

.action-button {
    gap: 9px;
    margin-top: 24px;
    padding: 0 22px;
}

.link-caption {
    margin-top: 9px;
    color: #64748b;
    font-size: 0.8rem;
}

.path-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
    margin-top: 24px;
    list-style: none;
}

.path-list li {
    display: flex;
    align-items: center;
    min-height: 50px;
    gap: 10px;
    padding: 10px 14px;
    border-radius: 13px;
    background: #f8fafc;
    color: #334155;
    font-size: 0.9rem;
}

.path-list span {
    display: grid;
    flex: 0 0 auto;
    width: 26px;
    height: 26px;
    place-items: center;
    border-radius: 50%;
    background: var(--blue-soft);
    color: var(--blue);
    font-size: 0.76rem;
    font-weight: 750;
}

.url-box {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    margin-top: 18px;
    padding: 16px 18px;
    border: 1px solid var(--line);
    border-radius: 15px;
}

.url-box > div {
    min-width: 0;
}

.url-box > div > span {
    display: block;
    color: #64748b;
    font-size: 0.75rem;
}

.url-box code {
    display: block;
    max-width: 100%;
    margin-top: 3px;
    overflow: hidden;
    color: var(--ink);
    font-size: 0.88rem;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.url-box button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
    min-height: 44px;
    gap: 7px;
    padding: 0 15px;
    border-radius: 11px;
    border: 0;
    background: var(--blue-soft);
    color: var(--blue-dark);
    font-size: 0.86rem;
    font-weight: 700;
    text-decoration: none;
    transition: background-color 180ms ease;
    cursor: pointer;
}

.url-box button:hover {
    background: #dbeafe;
}

.nowrap {
    white-space: nowrap;
}

.url-box button svg {
    width: 17px;
    height: 17px;
}

.url-box button.is-copied {
    background: #dcfce7;
    color: #166534;
}

.video-button {
    display: flex;
    align-items: center;
    gap: 14px;
    max-width: 480px;
    min-height: 74px;
    margin-top: 24px;
    padding: 10px 16px 10px 11px;
    border: 1px solid var(--line);
    border-radius: 17px;
    color: var(--ink);
    text-decoration: none;
    transition: border-color 180ms ease, box-shadow 180ms ease;
}

.video-button:hover {
    border-color: #bfdbfe;
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.09);
}

.play-icon {
    display: grid;
    flex: 0 0 auto;
    width: 52px;
    height: 52px;
    place-items: center;
    border-radius: 14px;
    background: var(--blue);
    color: #fff;
}

.play-icon svg {
    width: 26px;
    height: 26px;
    fill: currentColor;
    stroke: none;
}

.video-button > span:nth-child(2) {
    display: flex;
    flex: 1;
    flex-direction: column;
    font-weight: 700;
    line-height: 1.4;
}

.video-button small {
    color: #64748b;
    font-size: 0.74rem;
    font-weight: 500;
}

.arrow-icon {
    width: 20px;
    height: 20px;
    color: #94a3b8;
}

.footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    max-width: 980px;
    min-height: 100px;
    margin: 0 auto;
    padding: 20px;
    border-top: 1px solid var(--line);
    color: #64748b;
    font-size: 0.84rem;
}

.footer a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    color: var(--blue-dark);
    font-weight: 650;
    text-decoration: none;
}

.hero .hero-note {
    margin-top: 10px;
    font-size: 0.8rem;
}

.inline-copy {
    padding: 0 2px;
    border: 0;
    border-bottom: 1px dashed currentColor;
    background: none;
    color: var(--blue-dark);
    font: inherit;
    font-weight: 700;
    cursor: pointer;
}

.step-copy > p + p {
    margin-top: 10px;
}

.step-copy > .url-box + p {
    margin-top: 18px;
}

.step-copy > p.tip {
    margin-top: 16px;
    padding: 12px 16px;
    border-radius: 13px;
    background: var(--blue-soft);
    color: #1e3a8a;
    font-size: 0.88rem;
}

.text-link {
    color: var(--blue-dark);
    font-weight: 650;
}

.video-button.is-pending {
    cursor: default;
    opacity: 0.7;
}

.video-button.is-pending:hover {
    border-color: var(--line);
    box-shadow: none;
}

.footer p + p {
    margin-top: 2px;
}

.footer .beian-link {
    min-height: 0;
    color: #64748b;
    font-weight: 500;
}

.footer .beian-link:hover {
    color: var(--blue-dark);
}

.toast {
    position: fixed;
    left: 50%;
    bottom: 32px;
    z-index: 100;
    max-width: calc(100% - 40px);
    padding: 11px 20px;
    border-radius: 999px;
    background: rgba(15, 23, 42, 0.9);
    color: #fff;
    font-size: 0.88rem;
    opacity: 0;
    transform: translate(-50%, 12px);
    transition: opacity 200ms ease, transform 200ms ease;
    pointer-events: none;
}

.toast.is-visible {
    opacity: 1;
    transform: translate(-50%, 0);
}

a:focus-visible,
button:focus-visible {
    border-radius: 8px;
    outline: 3px solid rgba(37, 99, 235, 0.4);
    outline-offset: 3px;
}

@media (max-width: 680px) {
    .nav-shell {
        width: calc(100% - 28px);
        height: 64px;
    }

    .brand-mark {
        width: 34px;
        height: 34px;
    }

    .back-link {
        font-size: 0.82rem;
    }

    .hero {
        min-height: 620px;
        padding: 125px 20px 85px;
    }

    .hero h1 {
        font-size: clamp(3.1rem, 16vw, 4.6rem);
    }

    .product-intro {
        grid-template-columns: 1fr;
        gap: 36px;
        width: calc(100% - 28px);
        padding: 84px 0;
    }

    .intro-copy {
        text-align: center;
    }

    .intro-copy > p {
        font-size: 1rem;
    }

    .feature-pills {
        justify-content: center;
    }

    .intro-visual {
        width: min(92%, 420px);
        margin: 0 auto;
    }

    .design-story {
        width: calc(100% - 28px);
        padding: 80px 0;
    }

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

    .element-card {
        display: flex;
        align-items: center;
        gap: 16px;
        padding: 18px 20px;
        text-align: left;
    }

    .element-icon {
        flex: 0 0 auto;
        width: 56px;
        height: 56px;
        margin: 0;
        border-radius: 18px;
    }

    .element-icon svg {
        width: 28px;
        height: 28px;
    }

    .element-card figcaption {
        margin-top: 0;
    }

    .tutorial {
        width: calc(100% - 28px);
        padding: 80px 0 64px;
    }

    .section-heading {
        margin-bottom: 32px;
    }

    .step-number {
        top: -12px;
        right: 16px;
        font-size: 5.8rem;
    }

    .step-body {
        grid-template-columns: 1fr;
        gap: 18px;
        padding: 28px 20px;
    }

    .step-icon {
        width: 52px;
        height: 52px;
        border-radius: 15px;
    }

    .path-list {
        grid-template-columns: 1fr;
    }

    .url-box {
        align-items: stretch;
        flex-direction: column;
        gap: 12px;
    }

    .url-box button {
        width: 100%;
    }

    .action-button {
        width: 100%;
    }

    .footer {
        align-items: flex-start;
        flex-direction: column;
        gap: 0;
        padding: 24px 20px;
    }
}

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

    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}

/* ====================
   手机端
==================== */
@media (max-width: 680px) {
    /* 顶部：固定的毛玻璃导航条 */
    .site-header {
        position: fixed;
        background: rgba(255, 255, 255, 0.85);
        -webkit-backdrop-filter: saturate(180%) blur(18px);
        backdrop-filter: saturate(180%) blur(18px);
        border-bottom: 1px solid rgba(15, 23, 42, 0.06);
    }

    .nav-shell {
        width: calc(100% - 40px);
        height: 56px;
    }

    .brand-mark {
        width: 30px;
        height: 30px;
        border-radius: 9px;
    }

    /* 首屏 */
    .hero {
        min-height: 0;
        padding: 112px 22px 72px;
    }

    .hero::before {
        width: 200px;
        height: 200px;
        left: -90px;
    }

    .hero::after {
        width: 160px;
        height: 160px;
        right: -70px;
    }

    .hero h1 {
        margin-top: 16px;
        font-size: clamp(3rem, 15vw, 3.9rem);
    }

    .hero p {
        margin-top: 22px;
        font-size: 1.02rem;
    }

    .hero .hero-note {
        margin-top: 8px;
        font-size: 0.82rem;
    }

    .primary-button {
        width: 100%;
        max-width: 320px;
        margin-top: 32px;
    }

    /* 产品介绍：图标在上，文字左对齐 */
    .product-intro {
        gap: 28px;
        padding: 72px 0;
    }

    .intro-visual {
        order: -1;
        width: 200px;
        padding: 0;
    }

    .intro-copy {
        text-align: left;
    }

    .intro-copy h2 {
        font-size: 2.6rem;
    }

    .intro-copy > p {
        margin-top: 18px;
    }

    .feature-pills {
        justify-content: flex-start;
        gap: 8px;
        margin-top: 22px;
    }

    .feature-pills span {
        padding: 6px 12px;
        font-size: 0.8rem;
    }

    /* 设计故事 */
    .design-story {
        padding: 72px 0;
    }

    .design-story blockquote {
        margin-top: 40px;
        font-size: 1.65rem;
    }

    .story-note {
        font-size: 0.95rem;
    }

    /* 安装步骤：图标和标题并排，正文占满整行 */
    .tutorial {
        padding: 72px 0 56px;
    }

    .section-heading p {
        font-size: 0.95rem;
    }

    .steps-list {
        gap: 16px;
    }

    .step-card {
        border-radius: 24px;
    }

    .step-number {
        top: 16px;
        right: 18px;
        color: #eef2f7;
        font-size: 3.4rem;
    }

    .step-body {
        grid-template-columns: 48px minmax(0, 1fr);
        column-gap: 14px;
        row-gap: 0;
        padding: 24px 20px;
    }

    .step-copy {
        display: contents;
    }

    .step-icon {
        grid-column: 1;
        grid-row: 1 / span 2;
        align-self: center;
        width: 48px;
        height: 48px;
        border-radius: 14px;
    }

    .step-icon svg {
        width: 24px;
        height: 24px;
    }

    .step-copy > .step-label {
        grid-column: 2;
        grid-row: 1;
        align-self: end;
        font-size: 0.74rem;
    }

    .step-copy > h3 {
        grid-column: 2;
        grid-row: 2;
        margin: 2px 0 0;
        font-size: 1.4rem;
    }

    .step-copy > :not(.step-label):not(h3) {
        grid-column: 1 / -1;
    }

    .step-copy > h3 + * {
        margin-top: 18px;
    }

    .step-copy > p:not(.step-label, .link-caption) {
        font-size: 0.95rem;
    }

    .notice {
        margin-top: 18px;
        padding: 16px;
    }

    /* 下载路径：合并成一个带分隔线的列表 */
    .path-list {
        gap: 0;
        margin-top: 16px;
        padding: 2px 14px;
        border-radius: 16px;
        background: #f8fafc;
    }

    .path-list li {
        min-height: 0;
        padding: 13px 0;
        border-radius: 0;
        background: none;
    }

    .path-list li + li {
        border-top: 1px solid #e9eef5;
    }

    .url-box {
        gap: 12px;
        padding: 14px;
    }

    .url-box code {
        overflow: visible;
        font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
        font-size: 0.86rem;
        white-space: normal;
        word-break: break-all;
    }

    .url-box button {
        min-height: 48px;
        background: var(--blue);
        color: #fff;
        font-size: 0.95rem;
    }

    .url-box button:hover {
        background: var(--blue-dark);
    }

    .url-box button.is-copied {
        background: #16a34a;
        color: #fff;
    }

    .video-button {
        max-width: none;
    }

    .footer {
        align-items: center;
        padding: 28px 20px 36px;
        text-align: center;
    }
}
