/* =============================================
   KNOWLEDGE HUB — Card-based SEO content
   Uses site CSS variables for auto-adaptation
   ============================================= */

/* Section wrapper */
.knowledge-hub-section {
    background: var(--color-bg, #fff);
    padding: 4rem 0 5rem;
    position: relative;
}
.knowledge-hub-section .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Section header */
.kh-section-header {
    text-align: center;
    margin-bottom: 3rem;
}
.kh-section-header .kh-eyebrow {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-primary, #2563eb);
    background: rgba(var(--color-primary-rgb, 37,99,235), 0.08);
    padding: 0.4rem 1.2rem;
    border-radius: 50px;
    margin-bottom: 1rem;
}
.kh-section-header h2 {
    font-size: 2.2rem;
    font-weight: 800;
    color: var(--color-heading, var(--color-secondary-dark, #1a1a2e));
    margin: 0 0 0.75rem;
    line-height: 1.25;
}
.kh-section-header p {
    font-size: 1.1rem;
    color: var(--color-text-light, #64748b);
    max-width: 680px;
    margin: 0 auto;
    line-height: 1.7;
}

/* Hub grid */
.knowledge-hub {
    display: grid;
    gap: 2rem;
}

/* Base card */
.knowledge-card {
    background: var(--color-bg-card, #fff);
    border-radius: 14px;
    border: 1px solid var(--color-border, rgba(0,0,0,0.08));
    box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    transition: box-shadow 0.3s ease, transform 0.3s ease;
    overflow: hidden;
}
.knowledge-card:hover {
    box-shadow: 0 8px 30px rgba(0,0,0,0.08);
    transform: translateY(-2px);
}

/* Card header */
.kcard-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem 2rem 0.75rem;
}
.kcard-icon {
    width: 48px;
    height: 48px;
    min-width: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.kcard-icon svg {
    width: 24px;
    height: 24px;
    stroke-width: 1.8;
    fill: none;
}
.kcard-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--color-heading, var(--color-secondary-dark, #1a1a2e));
    line-height: 1.3;
}

/* Icon color themes */
.kcard-icon--blue { background: rgba(var(--color-primary-rgb, 37,99,235), 0.1); }
.kcard-icon--blue svg { stroke: var(--color-primary, #2563eb); }
.kcard-icon--amber { background: rgba(245,158,11,0.1); }
.kcard-icon--amber svg { stroke: #d97706; }
.kcard-icon--green { background: rgba(16,185,129,0.08); }
.kcard-icon--green svg { stroke: #059669; }
.kcard-icon--purple { background: rgba(139,92,246,0.08); }
.kcard-icon--purple svg { stroke: #7c3aed; }
.kcard-icon--rose { background: rgba(244,63,94,0.07); }
.kcard-icon--rose svg { stroke: #e11d48; }
.kcard-icon--teal { background: rgba(20,184,166,0.08); }
.kcard-icon--teal svg { stroke: #0d9488; }
.kcard-icon--indigo { background: rgba(99,102,241,0.08); }
.kcard-icon--indigo svg { stroke: #4f46e5; }

/* Tag labels */
.kcard-tag {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    margin-bottom: 0.75rem;
}
.kcard-tag--guide { background: rgba(var(--color-primary-rgb, 37,99,235), 0.08); color: var(--color-primary, #2563eb); }
.kcard-tag--career { background: rgba(16,185,129,0.08); color: #059669; }
.kcard-tag--money { background: rgba(245,158,11,0.08); color: #b45309; }
.kcard-tag--tips { background: rgba(139,92,246,0.08); color: #7c3aed; }
.kcard-tag--tech { background: rgba(99,102,241,0.08); color: #4f46e5; }
.kcard-tag--risk { background: rgba(244,63,94,0.07); color: #e11d48; }
.kcard-tag--growth { background: rgba(20,184,166,0.08); color: #0d9488; }
.kcard-tag--compare { background: rgba(245,158,11,0.08); color: #92400e; }

/* Card body */
.kcard-body {
    padding: 0.25rem 2rem 1.75rem;
    font-size: 1rem;
    line-height: 1.8;
    color: var(--color-text, #374151);
}
.kcard-body p {
    margin: 0 0 1rem;
    line-height: 1.8;
}
.kcard-body p:last-child { margin-bottom: 0; }

/* Expandable area */
.kcard-expandable {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
.kcard-expandable.expanded {
    max-height: 4000px;
}
.kcard-expandable h3 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--color-heading, var(--color-secondary-dark, #1a1a2e));
    margin: 1.5rem 0 0.75rem;
    padding-top: 1rem;
    border-top: 1px solid var(--color-border, rgba(0,0,0,0.06));
}
.kcard-expandable h3:first-child {
    margin-top: 0.5rem;
}

/* Expand button */
.kcard-expand-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: none;
    border: none;
    color: var(--color-primary, #2563eb);
    font-size: 0.92rem;
    font-weight: 600;
    cursor: pointer;
    padding: 0.5rem 0;
    margin-top: 0.5rem;
    transition: color 0.2s;
}
.kcard-expand-btn:hover {
    color: var(--color-primary-dark, #1d4ed8);
}
.kcard-expand-btn svg {
    width: 18px;
    height: 18px;
    transition: transform 0.3s ease;
    stroke: currentColor;
    fill: none;
    stroke-width: 2;
}
.kcard-expand-btn[aria-expanded="true"] svg {
    transform: rotate(180deg);
}

/* Split card (image + text) */
.kcard-split {
    display: grid;
    grid-template-columns: 1fr 1fr;
}
.kcard-split .kcard-media {
    overflow: hidden;
    min-height: 300px;
}
.kcard-split .kcard-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}
.kcard-split:hover .kcard-media img {
    transform: scale(1.03);
}
.kcard-split .kcard-text {
    padding: 0;
}
.kcard-split .kcard-text .kcard-header {
    padding-top: 1.75rem;
}

/* Split reversed */
.kcard-split--reverse {
    direction: rtl;
}
.kcard-split--reverse > * {
    direction: ltr;
}

/* Paired cards (2-column grid) */
.knowledge-grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

/* =============================================
   INTERNAL CONTENT ELEMENTS (inside cards)
   ============================================= */

/* Data tables */
.kcard-table-wrap {
    margin: 1.25rem 0;
    border-radius: 10px;
    overflow: hidden;
    border: 1px solid var(--color-border, rgba(0,0,0,0.08));
}
.kcard-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.88rem;
}
.kcard-table thead {
    background: linear-gradient(135deg, var(--color-secondary-dark, #1a1a2e), var(--color-secondary, #2d2d5e));
}
.kcard-table th {
    padding: 0.85rem 1.1rem;
    color: #fff;
    font-weight: 600;
    text-align: left;
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}
.kcard-table td {
    padding: 0.75rem 1.1rem;
    border-bottom: 1px solid var(--color-border, rgba(0,0,0,0.06));
    color: var(--color-text, #374151);
    font-size: 0.88rem;
}
.kcard-table tbody tr:nth-child(even) { background: rgba(0,0,0,0.02); }
.kcard-table tbody tr:hover { background: rgba(var(--color-primary-rgb, 37,99,235), 0.04); }

/* Blockquotes */
.kcard-quote {
    margin: 1.5rem 0;
    padding: 1.25rem 1.5rem 1.25rem 1.75rem;
    background: linear-gradient(135deg, rgba(var(--color-primary-rgb, 37,99,235), 0.04), rgba(var(--color-primary-rgb, 37,99,235), 0.02));
    border-left: 4px solid var(--color-primary, #2563eb);
    border-radius: 0 10px 10px 0;
    position: relative;
}
.kcard-quote::before {
    content: "\201C";
    position: absolute;
    top: -0.2rem;
    left: 0.5rem;
    font-size: 3rem;
    color: var(--color-primary, #2563eb);
    opacity: 0.2;
    font-family: Georgia, serif;
    line-height: 1;
}
.kcard-quote p {
    font-style: italic;
    color: var(--color-heading, #1e293b);
    margin: 0 0 0.5rem;
    line-height: 1.7;
}
.kcard-quote cite {
    font-size: 0.85rem;
    color: var(--color-text-light, #64748b);
    font-style: normal;
    font-weight: 600;
}

/* Tip box */
.kcard-tip {
    margin: 1.25rem 0;
    padding: 1rem 1.25rem;
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    border-left: 4px solid #22c55e;
    border-radius: 0 10px 10px 0;
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}
.kcard-tip-icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    background: #22c55e;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.kcard-tip-icon svg { width: 16px; height: 16px; fill: #fff; stroke: none; }
.kcard-tip-body { flex: 1; min-width: 0; }
.kcard-tip-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: #166534;
    margin-bottom: 0.25rem;
}
.kcard-tip-text {
    font-size: 0.9rem;
    line-height: 1.65;
    color: #374151;
    margin: 0;
}

/* Warning box */
.kcard-warn {
    margin: 1.25rem 0;
    padding: 1rem 1.25rem;
    background: #fffbeb;
    border: 1px solid #fde68a;
    border-left: 4px solid #f59e0b;
    border-radius: 0 10px 10px 0;
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}
.kcard-warn-icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    background: #f59e0b;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.kcard-warn-icon svg { width: 16px; height: 16px; fill: #fff; stroke: none; }
.kcard-warn-body { flex: 1; min-width: 0; }
.kcard-warn-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: #92400e;
    margin-bottom: 0.25rem;
}
.kcard-warn-text {
    font-size: 0.9rem;
    line-height: 1.65;
    color: #374151;
    margin: 0;
}

/* Key/Info box */
.kcard-key {
    margin: 1.25rem 0;
    padding: 1rem 1.25rem;
    background: #eff6ff;
    border: 1px solid #bfdbfe;
    border-left: 4px solid var(--color-primary, #2563eb);
    border-radius: 0 10px 10px 0;
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}
.kcard-key-icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    background: var(--color-primary, #2563eb);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.kcard-key-icon svg { width: 16px; height: 16px; fill: #fff; stroke: none; }
.kcard-key-body { flex: 1; min-width: 0; }
.kcard-key-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: #1e40af;
    margin-bottom: 0.25rem;
}
.kcard-key-text {
    font-size: 0.9rem;
    line-height: 1.65;
    color: #374151;
    margin: 0;
}

/* Stats row */
.kcard-stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin: 1.5rem 0;
}
.kcard-stat-card {
    background: linear-gradient(135deg, var(--color-secondary-dark, #1a1a2e), var(--color-secondary, #2d2d5e));
    border-radius: 10px;
    padding: 1.25rem;
    text-align: center;
    color: #fff;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
}
.kcard-stat-num {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--color-primary-light, var(--color-primary, #60a5fa));
    margin-bottom: 0.2rem;
}
.kcard-stat-label {
    font-size: 0.75rem;
    color: rgba(255,255,255,0.7);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Lists inside cards */
.kcard-body ul, .kcard-body ol {
    padding-left: 1.5rem;
    margin: 0.75rem 0 1rem;
}
.kcard-body li {
    margin: 0.35rem 0;
    line-height: 1.7;
    font-size: 0.95rem;
}
.kcard-body li::marker {
    color: var(--color-primary, #2563eb);
}

/* Footnote / source reference */
.kcard-footnote {
    margin-top: 1rem;
    padding-top: 0.75rem;
    border-top: 1px dashed var(--color-border, rgba(0,0,0,0.1));
    font-size: 0.8rem;
    color: var(--color-text-light, #94a3b8);
    font-style: italic;
}

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 992px) {
    .kcard-split {
        grid-template-columns: 1fr;
    }
    .kcard-split .kcard-media {
        min-height: auto;
        max-height: 260px;
    }
    .kcard-split--reverse {
        direction: ltr;
    }
    .knowledge-grid-2 {
        grid-template-columns: 1fr;
    }
    .kh-section-header h2 {
        font-size: 1.8rem;
    }
    .kcard-stats-row {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .knowledge-hub-section {
        padding: 3rem 0 3.5rem;
    }
    .kcard-header {
        padding: 1.25rem 1.25rem 0.5rem;
    }
    .kcard-body {
        padding: 0.25rem 1.25rem 1.25rem;
    }
    .kcard-stats-row {
        grid-template-columns: 1fr 1fr;
    }
    .kcard-split .kcard-text .kcard-header {
        padding-top: 1.25rem;
    }
    .kh-section-header h2 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .kcard-stats-row {
        grid-template-columns: 1fr;
    }
    .kcard-title {
        font-size: 1.15rem;
    }
    .kcard-icon {
        width: 40px;
        height: 40px;
        min-width: 40px;
    }
}

/* =============================================
   DARK THEME SUPPORT (for dark-bg sites)
   ============================================= */
.knowledge-hub-section.kh-dark {
    background: var(--color-bg-dark, #0a0a1f);
}
.kh-dark .knowledge-card {
    background: rgba(255,255,255,0.04);
    border-color: rgba(255,255,255,0.08);
}
.kh-dark .knowledge-card:hover {
    box-shadow: 0 8px 30px rgba(0,0,0,0.3);
    background: rgba(255,255,255,0.06);
}
.kh-dark .kcard-title {
    color: #f1f5f9;
}
.kh-dark .kcard-body {
    color: #cbd5e1;
}
.kh-dark .kcard-body p {
    color: #cbd5e1;
}
.kh-dark .kcard-expandable h3 {
    color: #e2e8f0;
    border-top-color: rgba(255,255,255,0.08);
}
.kh-dark .kcard-table td {
    color: #cbd5e1;
    border-bottom-color: rgba(255,255,255,0.06);
}
.kh-dark .kcard-table tbody tr:nth-child(even) {
    background: rgba(255,255,255,0.02);
}
.kh-dark .kcard-table tbody tr:hover {
    background: rgba(var(--color-primary-rgb, 37,99,235), 0.08);
}
.kh-dark .kcard-quote {
    background: rgba(var(--color-primary-rgb, 37,99,235), 0.06);
}
.kh-dark .kcard-quote p { color: #e2e8f0; }
.kh-dark .kcard-quote cite { color: #94a3b8; }
.kh-dark .kcard-tip { background: rgba(34,197,94,0.08); border-color: rgba(34,197,94,0.2); }
.kh-dark .kcard-tip-title { color: #4ade80; }
.kh-dark .kcard-tip-text { color: #cbd5e1; }
.kh-dark .kcard-warn { background: rgba(245,158,11,0.08); border-color: rgba(245,158,11,0.2); }
.kh-dark .kcard-warn-title { color: #fbbf24; }
.kh-dark .kcard-warn-text { color: #cbd5e1; }
.kh-dark .kcard-key { background: rgba(var(--color-primary-rgb, 37,99,235), 0.08); border-color: rgba(var(--color-primary-rgb, 37,99,235), 0.2); }
.kh-dark .kcard-key-title { color: var(--color-primary-light, #60a5fa); }
.kh-dark .kcard-key-text { color: #cbd5e1; }
.kh-dark .kcard-body li { color: #cbd5e1; }
.kh-dark .kcard-footnote { color: #64748b; border-top-color: rgba(255,255,255,0.06); }
.kh-dark .kh-section-header h2 { color: #f1f5f9; }
.kh-dark .kh-section-header p { color: #94a3b8; }
.kh-dark .kcard-tag--guide { background: rgba(var(--color-primary-rgb, 37,99,235), 0.12); }
.kh-dark .kcard-stat-card { box-shadow: 0 4px 15px rgba(0,0,0,0.3); }

/* Fade up animation */
.kh-fade-up {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.kh-fade-up.kh-visible {
    opacity: 1;
    transform: translateY(0);
}