:root {
    --blue: #1677ff;
    --blue-dark: #0f376f;
    --blue-soft: #eaf3ff;
    --ink: #13213a;
    --muted: #66758b;
    --line: #dfe7f2;
    --bg: #f5f8fc;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", sans-serif;
    -webkit-font-smoothing: antialiased;
}

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

.intro-header {
    width: min(1180px, calc(100% - 40px));
    height: 76px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin: 0 auto;
}

.intro-brand {
    display: flex;
    align-items: center;
    gap: 11px;
}

.intro-brand > span {
    width: 38px;
    height: 38px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
}

.intro-brand strong,
.intro-brand small {
    display: block;
}

.intro-brand strong {
    font-size: 17px;
    letter-spacing: .08em;
}

.intro-brand small {
    margin-top: 2px;
    color: var(--muted);
    font-size: 10px;
}

.intro-header nav {
    display: flex;
    align-items: center;
    gap: 25px;
    color: #506079;
    font-size: 13px;
}

.intro-nav-login {
    padding: 9px 17px;
    border: 1px solid #b8d3f7;
    border-radius: 8px;
    color: var(--blue);
    font-weight: 700;
}

main {
    width: min(1180px, calc(100% - 40px));
    margin: 0 auto;
}

.intro-hero {
    min-height: 540px;
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(360px, .75fr);
    align-items: center;
    gap: 70px;
    padding: 70px 50px;
    overflow: hidden;
    border: 1px solid #d6e4f6;
    border-radius: 24px;
    background:
        radial-gradient(circle at 88% 12%, rgba(22,119,255,.13), transparent 27%),
        linear-gradient(135deg, #fff 0%, #f5f9ff 100%);
}

.intro-kicker {
    margin: 0 0 11px;
    color: var(--blue);
    font-size: 11px;
    font-weight: 800;
    letter-spacing: .18em;
    text-transform: uppercase;
}

.intro-hero h1 {
    max-width: 630px;
    margin: 0;
    font-family: "Songti SC", "STSong", serif;
    font-size: clamp(42px, 5.4vw, 68px);
    line-height: 1.14;
    letter-spacing: -.03em;
}

.intro-lead {
    max-width: 560px;
    margin: 24px 0 0;
    color: var(--muted);
    font-size: 17px;
    line-height: 1.8;
}

.intro-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 30px;
}

.intro-primary,
.intro-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 0 22px;
    border-radius: 9px;
    font-size: 14px;
    font-weight: 700;
}

.intro-primary {
    background: var(--blue);
    color: #fff;
    box-shadow: 0 9px 24px rgba(22,119,255,.2);
}

.intro-secondary {
    border: 1px solid #c9d8eb;
    background: #fff;
    color: #36506f;
}

.intro-feature-line {
    display: flex;
    flex-wrap: wrap;
    gap: 9px 20px;
    margin-top: 30px;
    color: #718097;
    font-size: 12px;
}

.intro-feature-line span::before {
    content: "✓";
    margin-right: 6px;
    color: var(--blue);
    font-weight: 800;
}

.intro-project-card {
    padding: 26px;
    border: 1px solid #d6e3f4;
    border-radius: 18px;
    background: rgba(255,255,255,.88);
    box-shadow: 0 22px 60px rgba(35,76,131,.12);
}

.intro-project-head,
.intro-progress-label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
}

.intro-project-head small,
.intro-project-head strong {
    display: block;
}

.intro-project-head small {
    margin-bottom: 5px;
    color: #8591a3;
    font-size: 10px;
}

.intro-project-head strong {
    font-size: 16px;
}

.intro-project-head > span {
    padding: 5px 9px;
    border-radius: 999px;
    background: var(--blue-soft);
    color: var(--blue);
    font-size: 11px;
    font-weight: 700;
}

.intro-progress-label {
    margin-top: 30px;
    color: #5b6b82;
    font-size: 12px;
}

.intro-progress-label strong {
    color: var(--blue);
    font-size: 18px;
}

.intro-progress {
    height: 8px;
    margin-top: 10px;
    overflow: hidden;
    border-radius: 999px;
    background: #e7edf5;
}

.intro-progress i {
    width: 30%;
    height: 100%;
    display: block;
    border-radius: inherit;
    background: var(--blue);
}

.intro-role-stack {
    display: flex;
    margin-top: 28px;
}

.intro-role-stack span {
    width: 36px;
    height: 36px;
    display: grid;
    place-items: center;
    margin-right: -5px;
    border: 2px solid #fff;
    border-radius: 50%;
    background: var(--blue-soft);
    color: #1568d9;
    font-size: 11px;
    font-weight: 800;
}

.intro-project-card > p {
    margin: 18px 0 0;
    color: #748198;
    font-size: 12px;
    line-height: 1.7;
}

.intro-section {
    padding: 96px 0 0;
}

.intro-section-title {
    max-width: 650px;
    margin-bottom: 30px;
}

.intro-section-title h2,
.intro-cta h2 {
    margin: 0;
    font-family: "Songti SC", "STSong", serif;
    font-size: clamp(28px, 4vw, 42px);
}

.intro-section-title > p:last-child {
    margin: 12px 0 0;
    color: var(--muted);
    font-size: 14px;
}

.intro-role-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
}

.intro-role-grid article {
    padding: 25px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #fff;
}

.intro-role-grid article > span {
    width: 35px;
    height: 35px;
    display: grid;
    place-items: center;
    border-radius: 9px;
    background: var(--blue-soft);
    color: var(--blue);
    font-size: 12px;
    font-weight: 800;
}

.intro-role-grid h3 {
    margin: 18px 0 8px;
    font-size: 16px;
}

.intro-role-grid p {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
    line-height: 1.75;
}

.intro-guide-section {
    padding-bottom: 96px;
}

.intro-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1px;
    margin: 0;
    padding: 0;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: var(--line);
    list-style: none;
}

.intro-steps li {
    min-height: 180px;
    padding: 24px;
    background: #fff;
}

.intro-steps li > span {
    color: var(--blue);
    font-size: 12px;
    font-weight: 800;
}

.intro-steps h3 {
    margin: 35px 0 8px;
    font-size: 15px;
}

.intro-steps p {
    margin: 0;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.7;
}

.intro-cta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 30px;
    margin-bottom: 70px;
    padding: 45px;
    border-radius: 18px;
    background: var(--blue-dark);
    color: #fff;
}

.intro-cta .intro-kicker {
    color: #7fb3ff;
}

.intro-cta .intro-actions {
    flex: 0 0 auto;
    margin: 0;
}

.intro-cta .intro-secondary {
    border-color: rgba(255,255,255,.25);
    background: transparent;
    color: #fff;
}

.intro-footer {
    width: min(1180px, calc(100% - 40px));
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin: 0 auto;
    padding: 25px 0 35px;
    border-top: 1px solid var(--line);
    color: #718097;
    font-size: 11px;
}

.intro-footer strong {
    margin-right: 12px;
    color: var(--ink);
}

@media (max-width: 850px) {
    .intro-hero {
        grid-template-columns: 1fr;
        gap: 45px;
        padding: 55px 35px;
    }

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

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

@media (max-width: 600px) {
    .intro-header,
    main,
    .intro-footer {
        width: min(100% - 24px, 1180px);
    }

    .intro-header nav > a:not(.intro-nav-login) {
        display: none;
    }

    .intro-hero {
        min-height: 0;
        padding: 42px 22px;
        border-radius: 17px;
    }

    .intro-hero h1 {
        font-size: 39px;
    }

    .intro-lead {
        font-size: 15px;
    }

    .intro-project-card {
        padding: 20px;
    }

    .intro-section {
        padding-top: 72px;
    }

    .intro-role-grid,
    .intro-steps {
        grid-template-columns: 1fr;
    }

    .intro-steps li {
        min-height: auto;
    }

    .intro-steps h3 {
        margin-top: 18px;
    }

    .intro-cta {
        align-items: flex-start;
        flex-direction: column;
        padding: 28px 22px;
    }

    .intro-footer div span {
        display: block;
        margin-top: 4px;
    }
}