/* ouyigai5 — Navy #1E3A8A + Yellow #FACC15 · Horizontal card bands */
:root {
    --navy: #1E3A8A;
    --navy-dark: #1E3A5F;
    --navy-soft: #2563EB;
    --yellow: #FACC15;
    --yellow-dark: #EAB308;
    --yellow-light: #FEF9C3;
    --white: #FFFFFF;
    --light: #F1F5F9;
    --light-soft: #E2E8F0;
    --text: #1E293B;
    --text-light: #64748B;
    --border: 1px solid #CBD5E1;
    --border-navy: 1px solid #1E40AF;
    --radius: 6px;
    --shadow: 0 4px 20px rgba(30, 58, 138, 0.15);
    --transition: 0.25s ease;
    --nav-h: 60px;
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html { scroll-behavior: smooth; overflow-x: hidden; }

body {
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.65;
    color: var(--text);
    background: var(--white);
    overflow-x: hidden;
    min-width: 0;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--navy); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--navy-soft); }
ul { list-style: none; }

.z54daccontainer {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    min-width: 0;
}

/* Sticky nav */
.z54dacmain-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--navy);
    border-bottom: 3px solid var(--yellow);
}
.z54dacmain-nav .z54daccontainer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: var(--nav-h);
    gap: 16px;
}
.z54daclogo a {
    font-size: 1.2rem;
    font-weight: 800;
    color: var(--yellow);
    white-space: nowrap;
}
.z54daclogo a:hover { color: var(--white); }

.z54dacnav-menu {
    display: flex;
    align-items: center;
    gap: 2px;
    flex-wrap: wrap;
}
.z54dacnav-menu a {
    display: block;
    padding: 8px 12px;
    color: rgba(255,255,255,0.85);
    font-size: 14px;
    font-weight: 500;
    border-radius: var(--radius);
    white-space: nowrap;
}
.z54dacnav-menu a:hover,
.z54dacnav-item.z54dacthis a { color: var(--navy); background: var(--yellow); }

.z54dacnav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    width: 40px;
    height: 40px;
    background: transparent;
    border: 1px solid rgba(250,204,21,0.5);
    border-radius: var(--radius);
    cursor: pointer;
    padding: 8px;
}
.z54dacnav-toggle span {
    display: block;
    height: 2px;
    background: var(--yellow);
    transition: var(--transition);
}
.z54dacnav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.z54dacnav-toggle.active span:nth-child(2) { opacity: 0; }
.z54dacnav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Hero band */
.z54dacintro-banner {
    background: var(--navy);
    color: var(--white);
    padding: 48px 0 56px;
    border-bottom: var(--border-navy);
}
.z54dacband-row {
    display: grid;
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 40px;
    align-items: center;
}
.z54dacband-label {
    display: inline-block;
    background: var(--yellow);
    color: var(--navy);
    font-size: 11px;
    font-weight: 800;
    letter-spacing: 0.1em;
    padding: 4px 12px;
    margin-bottom: 16px;
}
.z54dacintro-banner h1 {
    font-size: clamp(1.6rem, 3.5vw, 2.4rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
}
.z54dacintro-text p {
    font-size: 0.95rem;
    color: rgba(255,255,255,0.8);
    margin-bottom: 10px;
    line-height: 1.7;
}
.z54dacaction-btns {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin: 28px 0 24px;
}
.z54dacbtn-primary,
.z54dacbtn-outline,
.z54dacdownload-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    font-size: 15px;
    font-weight: 700;
    border-radius: var(--radius);
    border: 1px solid transparent;
    cursor: pointer;
    transition: var(--transition);
    min-width: 0;
}
.z54dacbtn-primary,
.z54dacdownload-btn {
    background: var(--yellow);
    color: var(--navy);
    border-color: var(--yellow);
}
.z54dacbtn-primary:hover,
.z54dacdownload-btn:hover { background: var(--yellow-dark); color: var(--navy-dark); }
.z54dacbtn-outline {
    background: transparent;
    color: var(--white);
    border-color: rgba(255,255,255,0.4);
}
.z54dacbtn-outline:hover { border-color: var(--yellow); color: var(--yellow); }

.z54dachero-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}
.z54dacstat-pill {
    background: rgba(255,255,255,0.08);
    border: var(--border-navy);
    padding: 8px 14px;
    font-size: 13px;
    color: rgba(255,255,255,0.85);
}
.z54dacstat-pill strong { color: var(--yellow); margin-right: 4px; }

.z54dacband-visual {
    border: var(--border-navy);
    border-left: 4px solid var(--yellow);
    overflow: hidden;
    background: var(--navy-dark);
}
.z54dacbanner-featured-image { width: 100%; aspect-ratio: 4/3; object-fit: cover; }

/* Keyword band */
.z54dackeyword-band {
    background: var(--yellow-light);
    padding: 12px 0;
    border-bottom: var(--border);
}
.z54dackeyword-band p {
    font-size: 12px;
    color: var(--text-light);
    text-align: center;
    line-height: 1.8;
}

/* Band headers */
.z54dacband-header { margin-bottom: 32px; }
.z54dacband-header h2 {
    font-size: clamp(1.4rem, 3vw, 1.85rem);
    font-weight: 800;
    color: var(--white);
    margin-bottom: 8px;
}
.z54dacband-header-light h2 { color: var(--navy); }
.z54dacband-header p,
.z54dacsection-desc { font-size: 0.95rem; color: rgba(255,255,255,0.75); }
.z54dacband-header-light p { color: var(--text-light); }

/* Download horizontal bands */
.z54dacdownload-section {
    padding: 56px 0;
    background: var(--navy-dark);
    border-bottom: 3px solid var(--yellow);
}
.z54dacdownload-bands { display: flex; flex-direction: column; gap: 12px; }
.z54dacdownload-band {
    display: grid;
    grid-template-columns: minmax(0, 72px) minmax(0, 1fr) minmax(0, auto);
    gap: 20px;
    align-items: center;
    padding: 20px 24px;
    background: var(--navy);
    border: var(--border-navy);
    min-width: 0;
    transition: var(--transition);
}
.z54dacdownload-band:hover { border-color: var(--yellow); }
.z54dacband-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--yellow);
    color: var(--navy);
    font-size: 12px;
    font-weight: 800;
    border-radius: var(--radius);
}
.z54dacband-info h3 { font-size: 1.05rem; color: var(--white); margin-bottom: 8px; }
.z54dacfeature-list li {
    font-size: 13px;
    color: rgba(255,255,255,0.75);
    padding: 3px 0 3px 14px;
    position: relative;
}
.z54dacfeature-list li::before {
    content: "—";
    position: absolute;
    left: 0;
    color: var(--yellow);
}
.z54dacband-action { text-align: right; min-width: 0; }
.z54dacband-ver { display: block; font-size: 11px; color: rgba(255,255,255,0.5); margin-top: 6px; }

/* Feature bands */
.z54dacfeatures-section {
    padding: 56px 0;
    background: var(--light);
    border-bottom: var(--border);
}
.z54dacfeature-bands { display: flex; flex-direction: column; gap: 12px; }
.z54dacfeature-band {
    display: grid;
    grid-template-columns: minmax(0, 64px) minmax(0, 1fr);
    gap: 20px;
    padding: 24px;
    background: var(--white);
    border: var(--border);
    border-left: 4px solid var(--yellow);
    min-width: 0;
}
.z54dacfeature-band-num {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--navy);
    opacity: 0.3;
}
.z54dacfeature-band-body h3 { font-size: 1.05rem; color: var(--navy); margin-bottom: 8px; }
.z54dacfeature-band-body p { font-size: 14px; color: var(--text-light); margin-bottom: 10px; line-height: 1.65; }
.z54dacfeature-details li {
    font-size: 13px;
    color: var(--text);
    padding: 3px 0 3px 16px;
    position: relative;
}
.z54dacfeature-details li::before {
    content: "▸";
    position: absolute;
    left: 0;
    color: var(--yellow-dark);
}

/* Guide bands */
.z54dacguide-section {
    padding: 56px 0;
    background: var(--navy);
    border-bottom: var(--border-navy);
}
.z54dacguide-bands { display: flex; flex-direction: column; gap: 12px; }
.z54dacguide-band {
    display: grid;
    grid-template-columns: minmax(0, 56px) minmax(0, 1fr);
    gap: 20px;
    padding: 24px;
    background: rgba(255,255,255,0.05);
    border: var(--border-navy);
    min-width: 0;
}
.z54dacstep-number {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--yellow);
    color: var(--navy);
    font-weight: 800;
    font-size: 14px;
    border-radius: var(--radius);
}
.z54dacstep-content h3 { font-size: 1rem; color: var(--white); margin-bottom: 8px; }
.z54dacstep-content p { font-size: 14px; color: rgba(255,255,255,0.75); margin-bottom: 8px; line-height: 1.65; }
.z54dacstep-details li {
    font-size: 13px;
    color: rgba(255,255,255,0.6);
    padding: 2px 0 2px 14px;
    position: relative;
}
.z54dacstep-details li::before { content: "·"; position: absolute; left: 4px; color: var(--yellow); }

/* Safe bands */
.z54dacsafe-section {
    padding: 56px 0;
    background: var(--white);
    border-bottom: var(--border);
}
.z54dacsafe-bands {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin-bottom: 32px;
}
.z54dacsafe-band {
    padding: 24px;
    background: var(--light);
    border: var(--border);
    border-top: 3px solid var(--navy);
    min-width: 0;
}
.z54dacsafe-band h3 { font-size: 1rem; color: var(--navy); margin-bottom: 8px; }
.z54dacsafe-band p { font-size: 14px; color: var(--text-light); margin-bottom: 10px; line-height: 1.65; }
.z54dacsafe-details li {
    font-size: 13px;
    padding: 3px 0 3px 16px;
    position: relative;
    color: var(--text);
}
.z54dacsafe-details li::before { content: "✓"; position: absolute; left: 0; color: var(--navy); font-weight: 700; }
.z54dacsafe-stats {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    padding: 24px;
    background: var(--navy);
    border: var(--border-navy);
    text-align: center;
}
.z54dacstat-number { font-size: 2rem; font-weight: 800; color: var(--yellow); }
.z54dacstat-label { font-size: 13px; color: rgba(255,255,255,0.7); margin-top: 4px; }

/* Support / footer nav */
.z54dacfooter-nav {
    padding: 56px 0;
    background: var(--navy-dark);
    border-bottom: 3px solid var(--yellow);
}
.z54dacfooter-nav-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 24px;
}
.z54dacfooter-nav-column h4 {
    font-size: 14px;
    color: var(--yellow);
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: var(--border-navy);
}
.z54dacfooter-nav-column li { margin-bottom: 8px; }
.z54dacfooter-nav-column a { color: rgba(255,255,255,0.75); font-size: 13px; }
.z54dacfooter-nav-column a:hover { color: var(--yellow); }

/* Articles */
.z54dachome-articles {
    padding: 56px 0;
    background: var(--light);
    border-bottom: var(--border);
}
.z54dachome-articles-grid {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 12px;
}
.z54dachome-article-card {
    border: var(--border);
    overflow: hidden;
    background: var(--white);
    min-width: 0;
    transition: var(--transition);
}
.z54dachome-article-card:hover { border-color: var(--navy); box-shadow: var(--shadow); }
.z54dachome-article-card a { color: inherit; display: block; }
.z54dachome-article-thumb { aspect-ratio: 16/10; overflow: hidden; background: var(--light-soft); }
.z54dachome-article-thumb img { width: 100%; height: 100%; object-fit: cover; }
.z54dachome-article-cap { padding: 12px; border-top: var(--border); }
.z54dachome-article-title { font-size: 13px; font-weight: 600; color: var(--text); line-height: 1.4; }

/* Links & ad */
.advertisement { padding: 16px 0; text-align: center; overflow: hidden; }
.z54dacrelated-links {
    padding: 32px 0;
    background: var(--white);
    border-top: var(--border);
    font-size: 13px;
}
.z54dacfriend-links { margin-bottom: 12px; }
.z54dacrelated-sites ul {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 16px;
}
.z54dacrelated-sites a { color: var(--text-light); }

/* Footer */
.z54dacsite-footer {
    background: var(--navy);
    color: rgba(255,255,255,0.7);
    padding: 32px 0;
    text-align: center;
    font-size: 13px;
}
.z54dacfooter-content p { margin-bottom: 6px; }
.z54dacfooter-content a { color: var(--yellow); }
.z54dacfooter-content strong { color: var(--white); }

/* Inner pages */
.z54dacbody-inner { background: var(--light); }
.z54dacnav-scroll {
    overflow-x: auto;
    flex-wrap: nowrap;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}
.z54dacnav-scroll::-webkit-scrollbar { display: none; }

.z54daclist-header {
    padding: 24px 0 16px;
    border-bottom: 3px solid var(--yellow);
    background: var(--white);
    margin-bottom: 24px;
}
.z54daclist-header h1 { font-size: 1.5rem; color: var(--navy); margin-bottom: 12px; }
.z54daclist-subnav {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 4px;
}
.z54daclist-subnav a {
    display: inline-block;
    padding: 6px 14px;
    font-size: 13px;
    background: var(--light);
    border: var(--border);
    color: var(--navy);
    white-space: nowrap;
    border-radius: var(--radius);
}
.z54daclist-subnav a:hover { background: var(--yellow); border-color: var(--yellow); }

.z54dactwo-col {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 280px);
    gap: 24px;
    padding-bottom: 48px;
    align-items: start;
}
.z54dacmain-col { min-width: 0; }

.z54daclist-box { display: flex; flex-direction: column; gap: 12px; }
.z54daclist-item {
    display: grid;
    grid-template-columns: minmax(0, 180px) minmax(0, 1fr);
    gap: 16px;
    padding: 16px;
    background: var(--white);
    border: var(--border);
    min-width: 0;
}
.z54daclist-thumb img { width: 100%; aspect-ratio: 16/10; object-fit: cover; border: var(--border); }
.z54daclist-title { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.z54daclist-title a { color: var(--navy); }
.z54daclist-info {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 12px;
    color: var(--text-light);
    margin-bottom: 8px;
}
.z54daclist-intro { font-size: 14px; color: var(--text-light); line-height: 1.6; }

.z54dacpagebar { margin-top: 24px; }
.z54dacpages a,
.z54dacpages span,
.pagelist a,
.pagelist span {
    display: inline-block;
    padding: 8px 14px;
    margin: 2px;
    border: var(--border);
    font-size: 14px;
    background: var(--white);
    color: var(--text);
}
.z54dacpages a:hover,
.pagelist a:hover,
.pagelist .thisclass {
    background: var(--navy);
    color: var(--white);
    border-color: var(--navy);
}

.z54dacchannel-block {
    margin-top: 24px;
    padding: 16px;
    background: var(--white);
    border: var(--border);
    border-left: 4px solid var(--yellow);
}
.z54dacchannel-block h4 { margin-bottom: 12px; }
.z54dacchannel-block h4 a { color: var(--navy); }
.z54daclike-block h3 { font-size: 1rem; color: var(--navy); margin-bottom: 12px; }

.z54dacsidebar { min-width: 0; }
.z54dacside-widget {
    background: var(--white);
    border: var(--border);
    padding: 20px;
    position: sticky;
    top: calc(var(--nav-h) + 12px);
}
.z54dacside-widget h3 {
    font-size: 1rem;
    color: var(--navy);
    margin-bottom: 14px;
    padding-bottom: 10px;
    border-bottom: var(--border);
}
.z54dacside-list li { border-bottom: var(--border); }
.z54dacside-list li:last-child { border-bottom: none; }
.z54dacside-item {
    display: grid;
    grid-template-columns: minmax(0, 72px) minmax(0, 1fr);
    gap: 10px;
    padding: 10px 0;
    min-width: 0;
}
.z54dacside-thumb img { width: 100%; aspect-ratio: 4/3; object-fit: cover; border: var(--border); }
.z54dacside-title { font-size: 13px; color: var(--text); font-weight: 600; line-height: 1.35; display: block; }
.z54dacside-desc { font-size: 12px; color: var(--text-light); display: block; margin-top: 4px; }

.z54dacinner-hero {
    background: var(--navy);
    color: var(--white);
    padding: 24px 0;
    border-bottom: 3px solid var(--yellow);
}
.z54dacbreadcrumb { font-size: 13px; margin-bottom: 12px; color: rgba(255,255,255,0.7); }
.z54dacbreadcrumb a { color: var(--yellow); }
.z54dacinner-hero h1 { font-size: 1.5rem; margin-bottom: 10px; }
.z54dacinner-meta { display: flex; flex-wrap: wrap; gap: 16px; font-size: 13px; color: rgba(255,255,255,0.7); }
.z54dacinner-meta a { color: var(--yellow); }
.z54dacinner-slide { margin: 16px auto; overflow: hidden; }

.z54dacarticle-litpic {
    margin-bottom: 24px;
    border: var(--border);
    overflow: hidden;
}
.z54dacarticle-litpic img { width: 100%; max-height: 420px; object-fit: cover; }
.z54dacarticle-body {
    background: var(--white);
    border: var(--border);
    padding: 28px;
    font-size: 16px;
    line-height: 1.8;
    min-width: 0;
    overflow-wrap: break-word;
}
.z54dacarticle-body img { max-width: 100%; height: auto; margin: 16px 0; }
.z54dacprenext { margin: 24px 0; padding: 16px; background: var(--white); border: var(--border); font-size: 14px; }
.z54dacprenext-stack p { margin-bottom: 8px; }
.z54dacrelated-as-thumb { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.z54dacrelated-thumb-card {
    display: block;
    border: var(--border);
    overflow: hidden;
    background: var(--white);
    min-width: 0;
}
.z54dacrelated-thumb-wrap img { width: 100%; aspect-ratio: 16/10; object-fit: cover; }
.z54dacrelated-thumb-body { padding: 12px; }
.z54dacrelated-thumb-title { font-size: 13px; font-weight: 600; color: var(--navy); display: block; }
.z54dacrelated-thumb-desc { font-size: 12px; color: var(--text-light); display: block; margin-top: 4px; }
.z54dacdiyfield { margin: 16px 0; }
.z54dacimages-gallery p { margin-bottom: 16px; }
.z54dacimages-gallery img { max-width: 100%; border: var(--border); }

/* Responsive */
@media (max-width: 1024px) {
    .z54dacband-row { grid-template-columns: minmax(0, 1fr); }
    .z54dachome-articles-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .z54dacfooter-nav-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .z54dactwo-col { grid-template-columns: minmax(0, 1fr); }
    .z54dacside-widget { position: static; }
    .z54dacsafe-bands { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 768px) {
    .z54dacnav-toggle { display: flex; }
    .z54dacmain-nav .z54daccontainer { position: relative; flex-wrap: wrap; }
    .z54dacnav-menu:not(.z54dacnav-scroll) {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--navy-dark);
        flex-direction: column;
        align-items: stretch;
        max-height: 0;
        overflow: hidden;
        transition: max-height var(--transition);
        border-bottom: var(--border-navy);
    }
    .z54dacnav-menu:not(.z54dacnav-scroll).active { max-height: 480px; overflow-y: auto; padding: 12px 20px 20px; }
    .z54dacnav-menu:not(.z54dacnav-scroll) a { padding: 12px 16px; }

    .z54dacbody-inner .z54dacnav-menu.z54dacnav-scroll {
        position: static;
        max-height: none;
        overflow-x: auto;
        flex-direction: row;
        flex-wrap: nowrap;
        display: none;
        padding: 0;
    }
    .z54dacbody-inner .z54dacnav-menu.z54dacnav-scroll.active {
        display: flex;
        flex-direction: column;
        overflow-x: visible;
        padding: 12px 20px 20px;
    }

    .z54dacdownload-band {
        grid-template-columns: minmax(0, 1fr);
        text-align: left;
    }
    .z54dacband-action { text-align: left; }
    .z54dacfeature-band { grid-template-columns: minmax(0, 1fr); }
    .z54dacfeature-band-num { display: none; }
    .z54dacsafe-stats { grid-template-columns: minmax(0, 1fr); }
    .z54dacfooter-nav-grid { grid-template-columns: minmax(0, 1fr); }
    .z54dachome-articles-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .z54daclist-item { grid-template-columns: minmax(0, 1fr); }
    .z54dacrelated-as-thumb { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 480px) {
    .z54daccontainer { padding: 0 16px; }
    .z54dachome-articles-grid { grid-template-columns: minmax(0, 1fr); }
    .z54dacaction-btns { flex-direction: column; }
    .z54dacbtn-primary, .z54dacbtn-outline { width: 100%; }
}

.z54dackw-strip {
    font-size: 14px;
    line-height: 1.65;
    color: var(--text-light);
    margin: 0 0 18px;
    padding: 12px 14px;
    background: var(--yellow-light);
    border: var(--border);
    border-left: 4px solid var(--navy);
    border-radius: 0 8px 8px 0;
}

.z54dackw-strip strong { color: var(--text); font-weight: 600; }

.z54daclist-header .z54dackw-strip { margin-top: 12px; }