:root {
    --ib-primary: #f0f9ff;          /* 主背景：浅冰川蓝 */
    --ib-secondary: #ecfeff;        /* 辅背景：冰川青 */
    --ib-accent: #0891b2;           /* 强调色：冰川深青 */
    --ib-accent-hover: #0e7490;     /* 强调色 hover */
    --ib-accent-soft: #06b6d4;      /* 强调色更亮 */
    --ib-text: #164e63;             /* 主文字：深青蓝 */
    --ib-text-muted: #64748b;       /* 弱文字：石板灰 */
    --ib-text-strong: #0f172a;      /* 强调文字：深墨 */
    --ib-card-bg: #ffffff;          /* 卡片背景 */
    --ib-border: #a5f3fc;           /* 边框：冰川蓝 */
    --ib-border-soft: #e0f2fe;      /* 弱边框 */
    --ib-warning: #f59e0b;          /* 警示色 */
    --ib-success: #10b981;          /* 成功色 */

    --ib-radius-sm: 6px;
    --ib-radius: 12px;
    --ib-radius-lg: 20px;
    --ib-shadow-sm: 0 2px 8px rgba(8, 145, 178, 0.06);
    --ib-shadow: 0 5px 15px rgba(100, 116, 139, 0.08);
    --ib-shadow-lg: 0 10px 30px rgba(8, 145, 178, 0.12);

    --ib-font: 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --ib-font-mono: 'JetBrains Mono', 'SF Mono', Consolas, monospace;
}

/* ---------- Reset & Base ---------- */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    margin: 0;
    font-family: var(--ib-font);
    background-color: var(--ib-primary);
    color: var(--ib-text);
    line-height: 1.6;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--ib-accent); text-decoration: none; transition: color .2s ease; }
a:hover { color: var(--ib-accent-hover); }
h1, h2, h3, h4, h5 { color: var(--ib-text-strong); margin: 0 0 .6em; line-height: 1.25; }
h1 { font-size: 2.6rem; font-weight: 800; }
h2 { font-size: 2rem; font-weight: 700; }
h3 { font-size: 1.3rem; font-weight: 600; }
p { margin: 0 0 1em; }
code { background: var(--ib-secondary); padding: 2px 8px; border-radius: 4px; font-family: var(--ib-font-mono); font-size: .9em; color: var(--ib-accent); }

.ib-container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }

/* ---------- Buttons ---------- */
.ib-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: var(--ib-radius-sm);
    font-weight: 600;
    font-size: 1rem;
    border: 1px solid transparent;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
    line-height: 1.4;
}
.ib-btn-primary { background-color: var(--ib-accent); color: #fff; }
.ib-btn-primary:hover { background-color: var(--ib-accent-hover); color: #fff; transform: translateY(-2px); box-shadow: var(--ib-shadow); }
.ib-btn-ghost { background: transparent; color: var(--ib-accent); border-color: var(--ib-border); }
.ib-btn-ghost:hover { background: var(--ib-secondary); color: var(--ib-accent-hover); }
.ib-btn-white { background: #fff; color: var(--ib-accent); }
.ib-btn-white:hover { background: var(--ib-primary); color: var(--ib-accent-hover); }
.ib-btn-lg { padding: 16px 36px; font-size: 1.05rem; }
.ib-btn-sm { padding: 8px 18px; font-size: .9rem; }

/* ---------- Section helpers ---------- */
.ib-section { padding: 80px 0; }
.ib-section-tight { padding: 50px 0; }
.ib-section-title { text-align: center; font-size: 2.2rem; font-weight: 700; margin-bottom: 15px; }
.ib-section-subtitle { text-align: center; font-size: 1.1rem; color: var(--ib-text-muted); max-width: 600px; margin: 0 auto 50px; }
.ib-muted { color: var(--ib-text-muted); }

/* ---------- Navigation ---------- */
.ib-nav {
    background-color: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--ib-border);
    position: sticky;
    top: 0;
    z-index: 100;
}
.ib-nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}
.ib-logo { font-size: 1.5rem; font-weight: 800; display: flex; align-items: center; color: var(--ib-text-strong); }
.ib-logo:hover { color: var(--ib-text-strong); }
.ib-logo-icon {
    background-color: var(--ib-accent);
    color: #fff;
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-right: 12px;
    font-weight: bold;
    font-size: 1.1rem;
    overflow: hidden;
}
.ib-logo-icon img { width: 100%; height: 100%; object-fit: cover; }
.ib-nav-links { display: flex; align-items: center; }
.ib-nav-links a:not(.ib-btn) { margin-left: 28px; font-size: 1rem; color: var(--ib-text-muted); font-weight: 500; }
.ib-nav-links a:not(.ib-btn):hover, .ib-nav-links a:not(.ib-btn).active { color: var(--ib-accent); }
.ib-nav-links .ib-btn { margin-left: 28px; }

.ib-menu-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; color: var(--ib-text); }
.ib-menu-toggle svg { width: 26px; height: 26px; }

.ib-mobile-menu { display: none; background: #fff; border-bottom: 1px solid var(--ib-border); }
.ib-mobile-menu.open { display: block; }
.ib-mobile-menu .ib-container { padding-top: 16px; padding-bottom: 16px; }
.ib-mobile-menu a:not(.ib-btn) { display: block; padding: 12px 0; color: var(--ib-text); border-bottom: 1px solid var(--ib-border-soft); }
.ib-mobile-menu a:not(.ib-btn):last-child { border-bottom: none; }
.ib-mobile-menu .ib-btn { display: block; margin-top: 16px; }

/* ---------- Hero ---------- */
.ib-hero { text-align: center; padding: 100px 0; background-color: #fff; }
.ib-hero h1 { font-size: 3.5rem; font-weight: 800; color: var(--ib-accent); margin-bottom: 20px; line-height: 1.2; }
.ib-hero h1 .accent { color: var(--ib-accent-soft); }
.ib-hero .lead { font-size: 1.2rem; color: var(--ib-text-muted); margin-bottom: 40px; max-width: 720px; margin-left: auto; margin-right: auto; }
.ib-hero-cta { display: inline-flex; flex-wrap: wrap; gap: 16px; justify-content: center; }

/* trust badges below hero */
.ib-trust-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 60px;
    padding-top: 40px;
    border-top: 1px dashed var(--ib-border);
}
.ib-trust-item { text-align: center; }
.ib-trust-item .num { font-size: 1.8rem; font-weight: 800; color: var(--ib-accent); font-family: var(--ib-font-mono); }
.ib-trust-item .lbl { color: var(--ib-text-muted); font-size: .9rem; margin-top: 4px; }

/* ---------- Features grid ---------- */
.ib-features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}
.ib-feature-item {
    background-color: var(--ib-card-bg);
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 30px;
    text-align: center;
    transition: all 0.3s ease;
}
.ib-feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(8, 145, 178, 0.1);
    border-color: var(--ib-accent-soft);
}
.ib-feature-icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--ib-accent);
    line-height: 1;
}
.ib-feature-item h3 { font-size: 1.3rem; margin-bottom: 10px; }
.ib-feature-item p { color: var(--ib-text-muted); font-size: 0.95rem; margin: 0; }

/* ---------- Download Banner (download-area) ---------- */
.ib-download-area { background-color: var(--ib-secondary); }
.ib-download-content {
    background-color: var(--ib-accent);
    border-radius: var(--ib-radius-lg);
    padding: 60px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 30px;
    background-image: linear-gradient(135deg, var(--ib-accent) 0%, var(--ib-accent-hover) 100%);
}
.ib-download-text h2 { color: #fff; font-size: 2rem; margin: 0 0 10px; }
.ib-download-text p { color: var(--ib-primary); opacity: .92; margin: 0; }
.ib-download-btn { background-color: #fff; color: var(--ib-accent); padding: 15px 35px; flex-shrink: 0; }
.ib-download-btn:hover { background-color: var(--ib-primary); color: var(--ib-accent-hover); }

/* ---------- Platform cards ---------- */
.ib-platforms-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
}
.ib-platform-card {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 28px;
    text-align: center;
    color: var(--ib-text);
    transition: all .3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
}
.ib-platform-card:hover { transform: translateY(-4px); box-shadow: var(--ib-shadow-lg); border-color: var(--ib-accent-soft); color: var(--ib-text); }
.ib-platform-card .ib-pico {
    width: 56px;
    height: 56px;
    background: var(--ib-secondary);
    color: var(--ib-accent);
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
}
.ib-platform-card .ib-pico svg { width: 32px; height: 32px; }
.ib-platform-card .ib-pname { font-size: 1.15rem; font-weight: 700; color: var(--ib-text-strong); margin-bottom: 6px; }
.ib-platform-card .ib-pmeta { color: var(--ib-text-muted); font-size: .85rem; margin-bottom: 16px; }
.ib-platform-card .ib-pdl {
    margin-top: auto;
    color: var(--ib-accent);
    font-weight: 600;
    font-size: .95rem;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

/* ---------- Testimonials ---------- */
.ib-testimonials-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}
.ib-testimonial-card {
    background-color: var(--ib-card-bg);
    border-left: 5px solid var(--ib-accent);
    border-radius: var(--ib-radius-sm);
    padding: 30px;
    box-shadow: var(--ib-shadow);
}
.ib-testimonial-text { font-style: italic; color: var(--ib-text-muted); margin-bottom: 20px; line-height: 1.7; }
.ib-testimonial-author { display: flex; align-items: center; }
.ib-testimonial-author .avatar {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    margin-right: 15px;
    background: var(--ib-accent);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1rem;
}
.ib-testimonial-author img { width: 45px; height: 45px; border-radius: 50%; margin-right: 15px; }
.ib-testimonial-author-info h4 { margin: 0; font-size: 1rem; color: var(--ib-text-strong); }
.ib-testimonial-author-info p { margin: 0; font-size: .9rem; color: var(--ib-text-muted); }

/* ---------- FAQ ---------- */
.ib-faq-list { max-width: 780px; margin: 0 auto; }
.ib-faq-item { border-bottom: 1px solid var(--ib-border); }
.ib-faq-question {
    padding: 20px 0;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--ib-text-strong);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}
.ib-faq-question .chev { width: 20px; height: 20px; flex-shrink: 0; color: var(--ib-text-muted); transition: transform .3s ease; }
.ib-faq-item.active .chev { transform: rotate(180deg); color: var(--ib-accent); }
.ib-faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height .35s ease, padding .35s ease;
    color: var(--ib-text-muted);
    padding-bottom: 0;
}
.ib-faq-item.active .ib-faq-answer { max-height: 600px; padding-bottom: 20px; }
.ib-faq-answer p { margin: 0 0 .8em; }
.ib-faq-answer ul { margin: .5em 0 1em; padding-left: 1.4em; }
.ib-faq-answer li { margin: .3em 0; }
.ib-faq-section { margin-bottom: 40px; }
.ib-faq-section > h2 { font-size: 1.5rem; padding-bottom: 12px; border-bottom: 2px solid var(--ib-accent); margin-bottom: 8px; }
.ib-faq-section > .sub { color: var(--ib-text-muted); font-size: .95rem; margin-bottom: 20px; }
.ib-faq-search {
    display: flex;
    align-items: center;
    gap: 10px;
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: 999px;
    padding: 10px 18px;
    max-width: 460px;
    margin: 24px auto 0;
}
.ib-faq-search svg { width: 18px; height: 18px; color: var(--ib-text-muted); }
.ib-faq-search input {
    border: 0;
    outline: 0;
    flex: 1;
    font-size: 1rem;
    background: transparent;
    color: var(--ib-text);
    font-family: inherit;
}

/* ---------- CTA ---------- */
.ib-cta { background-color: var(--ib-secondary); text-align: center; }

/* ---------- Footer ---------- */
.ib-footer {
    background-color: var(--ib-secondary);
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--ib-border);
}
.ib-footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    text-align: left;
    margin-bottom: 30px;
}
.ib-footer-grid h5 { color: var(--ib-text-strong); margin: 0 0 14px; font-size: 1rem; }
.ib-footer-grid ul { list-style: none; padding: 0; margin: 0; }
.ib-footer-grid li { margin-bottom: 8px; }
.ib-footer-grid a { color: var(--ib-text-muted); font-size: .92rem; }
.ib-footer-grid a:hover { color: var(--ib-accent); }
.ib-footer .footer-tag { color: var(--ib-text-muted); font-size: .92rem; margin: 12px 0 0; }
.ib-friend-links {
    margin: 24px 0;
    padding: 18px 0;
    border-top: 1px dashed var(--ib-border);
    text-align: left;
}
.ib-friend-links h5 { color: var(--ib-text-strong); font-size: .95rem; margin: 0 0 10px; }
.ib-friend-links-list {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 13px;
}
.ib-friend-links-list a { color: var(--ib-text-muted); }
.ib-friend-links-list a:hover { color: var(--ib-accent); }
.ib-footer-bottom {
    padding-top: 20px;
    border-top: 1px solid var(--ib-border);
    color: var(--ib-text-muted);
    font-size: .9rem;
}

/* ---------- Eyebrow / Page hero ---------- */
.ib-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--ib-accent);
    font-size: .85rem;
    font-weight: 600;
    letter-spacing: .05em;
    text-transform: uppercase;
    background: var(--ib-secondary);
    padding: 6px 14px;
    border-radius: 999px;
    margin-bottom: 16px;
}
.ib-eyebrow .dot { width: 6px; height: 6px; background: var(--ib-accent); border-radius: 50%; }

.ib-page-hero { background: #fff; padding: 80px 0 50px; border-bottom: 1px solid var(--ib-border); }
.ib-page-hero h1 { font-size: 2.6rem; color: var(--ib-accent); margin-bottom: 14px; }
.ib-page-hero .lead { font-size: 1.1rem; color: var(--ib-text-muted); max-width: 720px; }
.ib-crumbs { color: var(--ib-text-muted); font-size: .9rem; margin-bottom: 14px; }
.ib-crumbs a { color: var(--ib-text-muted); }
.ib-crumbs a:hover { color: var(--ib-accent); }
.ib-crumbs .sep { margin: 0 8px; }

/* ---------- Article list ---------- */
.ib-featured {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    overflow: hidden;
    margin-bottom: 40px;
    transition: all .3s ease;
    color: var(--ib-text);
}
.ib-featured:hover { box-shadow: var(--ib-shadow-lg); transform: translateY(-2px); color: var(--ib-text); }
.ib-featured-cover {
    background: linear-gradient(135deg, var(--ib-accent) 0%, var(--ib-accent-soft) 100%);
    min-height: 280px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}
.ib-featured-cover::before, .ib-featured-cover::after {
    content: '';
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.12);
}
.ib-featured-cover::before { width: 180px; height: 180px; top: -40px; right: -40px; }
.ib-featured-cover::after { width: 120px; height: 120px; bottom: -30px; left: -30px; }
.ib-featured-body { padding: 36px; display: flex; flex-direction: column; justify-content: center; }
.ib-featured-label { color: var(--ib-warning); font-size: .85rem; font-weight: 700; letter-spacing: .05em; margin-bottom: 12px; }
.ib-featured-body h2 { font-size: 1.6rem; margin-bottom: 12px; }
.ib-featured-body p { color: var(--ib-text-muted); margin-bottom: 16px; }
.ib-featured-meta { color: var(--ib-text-muted); font-size: .85rem; display: flex; gap: 8px; flex-wrap: wrap; }

.ib-articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
}
.ib-article-card {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    overflow: hidden;
    transition: all .3s ease;
    color: var(--ib-text);
    display: flex;
    flex-direction: column;
}
.ib-article-card:hover { transform: translateY(-3px); box-shadow: var(--ib-shadow); border-color: var(--ib-accent-soft); color: var(--ib-text); }
.ib-article-cover {
    height: 140px;
    background: linear-gradient(135deg, var(--ib-accent-soft) 0%, var(--ib-accent) 100%);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}
.ib-article-cover .glyph { color: #fff; font-size: 1.8rem; font-weight: 800; font-family: var(--ib-font-mono); letter-spacing: -.02em; }
.ib-article-cover.cover-2 { background: linear-gradient(135deg, #67e8f9 0%, var(--ib-accent) 100%); }
.ib-article-cover.cover-3 { background: linear-gradient(135deg, var(--ib-accent-hover) 0%, #155e75 100%); }
.ib-article-cover.cover-4 { background: linear-gradient(135deg, #22d3ee 0%, var(--ib-accent-soft) 100%); }
.ib-article-cover.cover-5 { background: linear-gradient(135deg, var(--ib-accent) 0%, #0e7490 100%); }
.ib-article-cover.cover-6 { background: linear-gradient(135deg, #06b6d4 0%, #155e75 100%); }
.ib-article-cover.cover-7 { background: linear-gradient(135deg, #0e7490 0%, var(--ib-accent-soft) 100%); }
.ib-article-cover.cover-8 { background: linear-gradient(135deg, #67e8f9 0%, #06b6d4 100%); }
.ib-article-cover.cover-9 { background: linear-gradient(135deg, var(--ib-accent-soft) 0%, #155e75 100%); }
.ib-article-body { padding: 20px; flex: 1; display: flex; flex-direction: column; }
.ib-article-tag {
    display: inline-block;
    background: var(--ib-secondary);
    color: var(--ib-accent);
    font-size: .75rem;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 999px;
    align-self: flex-start;
    margin-bottom: 10px;
}
.ib-article-body h3 { font-size: 1.05rem; margin-bottom: 8px; line-height: 1.4; }
.ib-article-body p { color: var(--ib-text-muted); font-size: .9rem; margin-bottom: 14px; }
.ib-article-meta {
    margin-top: auto;
    color: var(--ib-text-muted);
    font-size: .8rem;
    display: flex;
    justify-content: space-between;
    border-top: 1px solid var(--ib-border-soft);
    padding-top: 12px;
}

.ib-articles-strip {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 22px;
    margin-top: 36px;
}
.ib-article-mini {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 22px;
    color: var(--ib-text);
    transition: all .3s ease;
}
.ib-article-mini:hover { transform: translateY(-3px); box-shadow: var(--ib-shadow); color: var(--ib-text); }
.ib-article-mini .tag { color: var(--ib-accent); font-size: .8rem; font-weight: 600; }
.ib-article-mini h3 { font-size: 1.05rem; margin: 8px 0 8px; }
.ib-article-mini p { color: var(--ib-text-muted); font-size: .9rem; margin-bottom: 12px; }
.ib-article-mini .meta { display: flex; justify-content: space-between; color: var(--ib-text-muted); font-size: .8rem; }

.ib-pagination { display: flex; justify-content: center; align-items: center; gap: 8px; margin: 36px 0; }
.ib-pagination ul { list-style: none; display: flex; gap: 8px; padding: 0; margin: 0; }
.ib-pagination a, .ib-pagination span {
    display: inline-block;
    padding: 8px 14px;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius-sm);
    color: var(--ib-text-muted);
    background: #fff;
    font-size: .9rem;
    text-decoration: none;
}
.ib-pagination a:hover { border-color: var(--ib-accent); color: var(--ib-accent); }
.ib-pagination .active, .ib-pagination .current { background: var(--ib-accent); color: #fff; border-color: var(--ib-accent); }
.ib-empty { text-align: center; padding: 80px 0; color: var(--ib-text-muted); font-size: 1.1rem; }

/* ---------- Article detail ---------- */
.ib-read-progress {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: transparent;
    z-index: 200;
}
.ib-read-progress .bar { height: 100%; width: 0; background: var(--ib-accent); transition: width .15s ease; }

.ib-article-hero { background: #fff; padding: 60px 0 30px; border-bottom: 1px solid var(--ib-border); }
.ib-article-hero h1 { font-size: 2.2rem; margin-bottom: 18px; }
.ib-article-meta-top { color: var(--ib-text-muted); font-size: .9rem; display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 16px; }
.ib-tag-mini { background: var(--ib-secondary); color: var(--ib-accent); padding: 3px 10px; border-radius: 999px; font-weight: 600; font-size: .8rem; }
.ib-article-author { display: flex; align-items: center; gap: 14px; margin-top: 22px; padding-top: 22px; border-top: 1px solid var(--ib-border-soft); }
.ib-article-author .avatar {
    width: 44px; height: 44px;
    background: var(--ib-accent); color: #fff;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-weight: 700;
}
.ib-article-author .name { font-weight: 600; color: var(--ib-text-strong); }
.ib-article-author .role { font-size: .85rem; color: var(--ib-text-muted); }

.ib-article-layout {
    display: grid;
    grid-template-columns: 220px 1fr 240px;
    gap: 40px;
    padding: 50px 0;
    align-items: start;
}
.ib-article-toc {
    position: sticky;
    top: 90px;
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 20px;
}
.ib-article-toc h4 { font-size: 1rem; margin-bottom: 12px; color: var(--ib-text-strong); }
.ib-article-toc ul { list-style: none; padding: 0; margin: 0; }
.ib-article-toc li { margin-bottom: 6px; }
.ib-article-toc a {
    color: var(--ib-text-muted);
    font-size: .9rem;
    display: block;
    padding: 4px 0 4px 8px;
    border-left: 2px solid transparent;
    transition: all .2s ease;
}
.ib-article-toc a:hover, .ib-article-toc a.active { color: var(--ib-accent); border-left-color: var(--ib-accent); }
.ib-article-toc .toc-h3 a { padding-left: 20px; font-size: .85rem; }

.ib-article-content {
    background: #fff;
    padding: 36px 40px;
    border-radius: var(--ib-radius);
    border: 1px solid var(--ib-border);
    font-size: 1.05rem;
    line-height: 1.85;
}
.ib-article-content h2 {
    font-size: 1.5rem;
    margin: 1.8em 0 .6em;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--ib-border-soft);
}
.ib-article-content h3 { font-size: 1.2rem; margin: 1.4em 0 .5em; }
.ib-article-content p { margin: 0 0 1.1em; }
.ib-article-content ul, .ib-article-content ol { margin: 0 0 1.1em 0; padding-left: 1.6em; }
.ib-article-content li { margin: .3em 0; }
.ib-article-content img { border-radius: var(--ib-radius-sm); margin: 1em auto; }
.ib-article-content a:not(.ib-btn) { color: var(--ib-accent); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; }
.ib-article-content blockquote {
    border-left: 4px solid var(--ib-accent);
    background: var(--ib-secondary);
    padding: 14px 20px;
    margin: 1.2em 0;
    color: var(--ib-text);
    border-radius: 0 var(--ib-radius-sm) var(--ib-radius-sm) 0;
}

.ib-end-cta {
    margin-top: 40px;
    padding: 30px;
    background: var(--ib-secondary);
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    text-align: center;
}
.ib-end-cta h3 { font-size: 1.2rem; margin-bottom: 8px; }
.ib-end-cta p { color: var(--ib-text-muted); margin-bottom: 18px; }

.ib-article-aside .share-block, .ib-article-aside .related-block {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 20px;
    margin-bottom: 20px;
    position: sticky;
    top: 90px;
}
.ib-article-aside .related-block { position: static; }
.ib-article-aside h5 { font-size: 1rem; margin-bottom: 12px; }
.ib-share-icons { display: flex; gap: 10px; }
.ib-share-icons a {
    width: 36px; height: 36px;
    background: var(--ib-secondary);
    border-radius: 50%;
    display: inline-flex; align-items: center; justify-content: center;
    color: var(--ib-accent);
}
.ib-share-icons svg { width: 18px; height: 18px; }
.ib-related-list { list-style: none; padding: 0; margin: 0; }
.ib-related-list li { padding: 10px 0; border-bottom: 1px solid var(--ib-border-soft); }
.ib-related-list li:last-child { border-bottom: none; }
.ib-related-list a { color: var(--ib-text); font-size: .95rem; font-weight: 500; }
.ib-related-list a:hover { color: var(--ib-accent); }
.ib-related-list .meta { font-size: .8rem; color: var(--ib-text-muted); margin-top: 4px; }

.ib-nav-articles {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 50px;
}
.ib-nav-link {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 20px;
    color: var(--ib-text);
    transition: all .3s ease;
}
.ib-nav-link:hover { border-color: var(--ib-accent); color: var(--ib-text); box-shadow: var(--ib-shadow); }
.ib-nav-link .nav-dir { color: var(--ib-text-muted); font-size: .85rem; margin-bottom: 6px; }
.ib-nav-link strong { color: var(--ib-text-strong); font-size: 1rem; }
.ib-nav-link.next { text-align: right; }

/* ---------- Download page ---------- */
.ib-download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.ib-dl-card {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 28px;
    transition: all .3s ease;
}
.ib-dl-card:hover { box-shadow: var(--ib-shadow); transform: translateY(-3px); border-color: var(--ib-accent-soft); }
.ib-dl-head { display: flex; gap: 16px; align-items: center; margin-bottom: 16px; }
.ib-dl-icon {
    width: 56px; height: 56px;
    background: var(--ib-secondary);
    color: var(--ib-accent);
    border-radius: var(--ib-radius);
    display: flex; align-items: center; justify-content: center;
}
.ib-dl-icon svg { width: 32px; height: 32px; }
.ib-dl-title h3 { margin: 0; font-size: 1.2rem; }
.ib-dl-title .meta { color: var(--ib-text-muted); font-size: .85rem; }
.ib-dl-body { color: var(--ib-text-muted); font-size: .95rem; margin-bottom: 16px; }
.ib-dl-specs { list-style: none; padding: 0; margin: 0 0 20px; display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.ib-dl-specs li { display: flex; align-items: center; gap: 8px; font-size: .9rem; color: var(--ib-text); }
.ib-dl-specs li svg { width: 16px; height: 16px; color: var(--ib-success); flex-shrink: 0; }
.ib-dl-actions .ib-btn { width: 100%; }
.ib-dl-meta-row { margin-top: 14px; font-size: .8rem; color: var(--ib-text-muted); display: flex; justify-content: space-between; }

.ib-sysreq {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
    margin-top: 30px;
}
.ib-sysreq-card { background: #fff; border: 1px solid var(--ib-border); border-radius: var(--ib-radius); padding: 22px; }
.ib-sysreq-card h4 { margin: 0 0 14px; color: var(--ib-accent); padding-bottom: 10px; border-bottom: 1px solid var(--ib-border-soft); }
.ib-sysreq-card dl { margin: 0; }
.ib-sysreq-card dt { font-size: .8rem; color: var(--ib-text-muted); margin-top: 8px; }
.ib-sysreq-card dt:first-child { margin-top: 0; }
.ib-sysreq-card dd { margin: 2px 0 0; font-size: .95rem; font-weight: 500; }

.ib-troubles-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 24px;
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    overflow: hidden;
}
.ib-troubles-table td { padding: 14px 20px; border-bottom: 1px solid var(--ib-border-soft); font-size: .95rem; }
.ib-troubles-table tr:last-child td { border-bottom: none; }
.ib-troubles-table td:first-child { font-weight: 600; color: var(--ib-accent); width: 30%; }

/* ---------- Privacy ---------- */
.ib-privacy-layout {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 40px;
    padding: 50px 0;
    align-items: start;
}
.ib-privacy-toc {
    position: sticky;
    top: 90px;
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 20px;
}
.ib-privacy-toc h4 { font-size: 1rem; margin-bottom: 12px; }
.ib-privacy-toc ul { list-style: none; padding: 0; margin: 0; }
.ib-privacy-toc li { margin-bottom: 8px; }
.ib-privacy-toc a { color: var(--ib-text-muted); font-size: .9rem; }
.ib-privacy-toc a:hover { color: var(--ib-accent); }
.ib-privacy-content {
    background: #fff;
    padding: 36px 40px;
    border-radius: var(--ib-radius);
    border: 1px solid var(--ib-border);
    font-size: 1.02rem;
    line-height: 1.8;
}
.ib-privacy-content h2 {
    font-size: 1.4rem;
    margin: 1.8em 0 .6em;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--ib-border-soft);
}
.ib-privacy-content h3 { font-size: 1.1rem; margin: 1.4em 0 .4em; }
.ib-privacy-content section { scroll-margin-top: 90px; }
.ib-ll-update { background: var(--ib-secondary); padding: 14px 18px; border-radius: var(--ib-radius-sm); font-size: .92rem; margin-bottom: 24px; }

.ib-pledge { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 20px; margin: 20px 0; }
.ib-pledge-card { background: var(--ib-secondary); border-radius: var(--ib-radius); padding: 24px; text-align: center; }
.ib-pledge-icon { width: 36px; height: 36px; color: var(--ib-accent); margin-bottom: 12px; }
.ib-pledge-card h4 { font-size: 1rem; margin-bottom: 8px; }
.ib-pledge-card p { color: var(--ib-text-muted); font-size: .9rem; margin: 0; }

.ib-do-dont {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 20px 0;
}
.ib-do-block, .ib-dont-block { padding: 20px; border-radius: var(--ib-radius); border: 1px solid; }
.ib-do-block { background: rgba(16, 185, 129, 0.06); border-color: rgba(16, 185, 129, 0.3); }
.ib-do-block b { color: var(--ib-success); display: block; margin-bottom: 10px; }
.ib-dont-block { background: rgba(245, 158, 11, 0.06); border-color: rgba(245, 158, 11, 0.3); }
.ib-dont-block b { color: var(--ib-warning); display: block; margin-bottom: 10px; }
.ib-do-block ul, .ib-dont-block ul { margin: 0; padding-left: 1.4em; }
.ib-do-block li, .ib-dont-block li { font-size: .92rem; margin: 4px 0; }

.ib-still-need {
    background: linear-gradient(135deg, var(--ib-accent) 0%, var(--ib-accent-hover) 100%);
    color: #fff;
    border-radius: var(--ib-radius-lg);
    padding: 40px;
    margin: 40px 0 60px;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
    align-items: center;
}
.ib-still-need h2 { color: #fff; margin-bottom: 8px; }
.ib-still-need p { color: rgba(255, 255, 255, 0.9); margin: 0; }
.ib-still-need .actions { display: flex; flex-direction: column; gap: 12px; }

/* ---------- How (3-step) ---------- */
.ib-how-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; margin-top: 30px; }
.ib-how-step {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius);
    padding: 28px;
    position: relative;
}
.ib-how-step .how-num {
    font-family: var(--ib-font-mono);
    color: var(--ib-accent);
    font-size: .9rem;
    font-weight: 700;
    margin-bottom: 14px;
    letter-spacing: .05em;
}
.ib-how-step h3 { font-size: 1.15rem; margin-bottom: 8px; }
.ib-how-step p { color: var(--ib-text-muted); margin: 0; font-size: .95rem; }

/* ---------- Final CTA card ---------- */
.ib-final-cta { padding: 60px 0 80px; background: var(--ib-secondary); }
.ib-cta-card {
    background: #fff;
    border: 1px solid var(--ib-border);
    border-radius: var(--ib-radius-lg);
    padding: 50px;
    text-align: center;
    box-shadow: var(--ib-shadow);
}
.ib-cta-card h2 { font-size: 2rem; margin-bottom: 12px; }
.ib-cta-card p { color: var(--ib-text-muted); font-size: 1.05rem; margin-bottom: 28px; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
    .ib-article-layout, .ib-privacy-layout { grid-template-columns: 1fr; }
    .ib-article-toc, .ib-privacy-toc { position: static; }
    .ib-article-aside .share-block { position: static; }
    .ib-featured { grid-template-columns: 1fr; }
    .ib-featured-cover { min-height: 180px; }
    .ib-footer-grid { grid-template-columns: repeat(2, 1fr); }
    .ib-still-need { grid-template-columns: 1fr; text-align: center; }
    .ib-still-need .actions { flex-direction: row; justify-content: center; }
}
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    .ib-section { padding: 50px 0; }
    .ib-hero { padding: 60px 0; }
    .ib-hero h1 { font-size: 2.2rem; }
    .ib-page-hero h1 { font-size: 2rem; }
    .ib-features-grid, .ib-testimonials-grid, .ib-how-grid { grid-template-columns: 1fr; }
    .ib-download-content { flex-direction: column; text-align: center; padding: 36px 24px; }
    .ib-download-text { margin-bottom: 20px; }
    .ib-nav-links { display: none; }
    .ib-menu-toggle { display: inline-flex; }
    .ib-section-title { font-size: 1.7rem; }
    .ib-footer-grid { grid-template-columns: 1fr; }
    .ib-trust-row { grid-template-columns: repeat(2, 1fr); }
    .ib-do-dont { grid-template-columns: 1fr; }
    .ib-article-content, .ib-privacy-content { padding: 24px 20px; }
    .ib-nav-articles { grid-template-columns: 1fr; }
    .ib-cta-card { padding: 36px 24px; }
    .ib-cta-card h2 { font-size: 1.5rem; }
}