/* ══════════════════════════════════════════════
   SOVEREIGN STRATEGIC PLAYBOOK HUB (v1.0.19.14)
   Aesthetic: Zenith Light (High-Contrast Industrial)
   ══════════════════════════════════════════════ */

/* HERO & LAYOUT CLEARANCE */
.playbook-hero {
    position: relative;
    padding-top: clamp(100px, 15vh, 140px); /* EXPERT: Absolute Navbar Clearance */
    padding-bottom: var(--sp-12);
    background: radial-gradient(at top center, var(--clr-gray-100), var(--clr-bg));
    border-bottom: 1px solid var(--clr-border);
    overflow: hidden;
}

.playbook-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image: var(--dot-pattern);
    opacity: 0.15;
    pointer-events: none;
}

.playbook-hero__badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px;
    background: var(--clr-bg-alt);
    border: 1px solid var(--clr-border);
    border-radius: var(--r-full);
    font-size: var(--fs-xs);
    font-weight: var(--fw-bold);
    color: var(--clr-gray-600);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--sp-6);
    box-shadow: var(--shadow-sm);
}

.playbook-hero__title {
    font-size: var(--fs-display);
    line-height: 1.2;
    color: var(--clr-gray-900);
    margin-bottom: var(--sp-6);
    max-width: 20ch;
}

.playbook-hero__title .text-accent {
    padding-bottom: 0.05em; /* EXPERT: Guard against gradient clipping */
}

.playbook-hero__desc {
    color: var(--clr-gray-600);
    font-size: var(--fs-lg);
    line-height: var(--lh-relaxed);
    max-width: 60ch;
}

/* STRATEGIC FILTERS (ZENITH LIGHT) */
.playbook-filters {
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-3);
    margin-top: var(--sp-12);
    padding: var(--sp-2) 0;
}

.filter-btn {
    padding: 8px 20px;
    border-radius: var(--r-full);
    font-size: var(--fs-sm);
    font-weight: var(--fw-bold);
    color: var(--clr-gray-600);
    background: var(--clr-bg-alt);
    border: 1px solid var(--clr-border);
    transition: all var(--t-spring);
    cursor: pointer;
    box-shadow: var(--shadow-sm);
}

.filter-btn:hover {
    color: var(--clr-accent-primary);
    border-color: var(--clr-accent-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.filter-btn.active {
    background: var(--clr-accent-primary);
    color: var(--clr-white);
    border-color: var(--clr-accent-primary);
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
}

/* ARCH-NODE SYSTEM (GLASS INDUSTRIAL) */
.playbook-grid {
    display: grid;
    gap: var(--sp-8);
    padding-block: var(--sp-12);
}

/* Mobile Default: Intelligence Stream (1-col) */
@media (max-width: 1023px) {
    .playbook-grid {
        grid-template-columns: 1fr;
    }
}

/* Desktop: Executive Grid (3-col) */
@media (min-width: 1024px) {
    .playbook-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.arch-node {
    position: relative;
    background: rgba(var(--clr-bg-alt-rgb), 0.6);
    backdrop-filter: blur(12px);
    border: 1px solid var(--clr-border);
    border-radius: var(--r-2xl);
    overflow: hidden; /* Guard for the visual shard */
    display: flex;
    flex-direction: column;
    min-height: 480px;
    transition: all var(--t-spring);
    text-decoration: none;
    box-shadow: var(--shadow-md);
}

.arch-node:hover {
    transform: translateY(-8px);
    border-color: var(--clr-accent-primary);
    box-shadow: 
        0 30px 60px -12px rgba(var(--clr-accent-primary-rgb), 0.15),
        0 0 0 1px var(--clr-accent-primary);
}

.arch-node__visual {
    width: 100%;
    height: 180px;
    background: var(--clr-gray-100);
    overflow: hidden;
    position: relative;
}

.node-mask {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(15, 23, 42, 0.5), transparent 60%);
    z-index: 1;
}

.arch-node__visual img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--t-relaxed);
    color: transparent; /* Hide alt text unless needed */
}

.arch-node:hover .arch-node__visual img {
    transform: scale(1.05);
}

.arch-node__content {
    padding: var(--sp-12) var(--sp-8) var(--sp-8); /* EXPERT: Absolute Clearance for Neural Shard */
    display: flex;
    flex-direction: column;
    gap: var(--sp-4);
    flex-grow: 1;
}

.node-status {
    position: absolute;
    bottom: var(--sp-4);
    right: var(--sp-4);
    font-family: 'JetBrains Mono', monospace;
    font-size: 9px;
    font-weight: 800;
    color: var(--clr-white);
    background: var(--clr-accent-primary);
    padding: 3px 10px;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    z-index: 2;
    box-shadow: 0 0 20px rgba(var(--clr-accent-primary-rgb), 0.5);
}

.arch-node__icon {
    position: absolute;
    top: 154px; /* Precisely centered on the visual boundary */
    left: var(--sp-8);
    width: 52px;
    height: 52px;
    background: #0f172a; /* Industrial Obsidian Core */
    border: 2px solid var(--clr-accent-primary); /* High-Authority Stroke */
    border-radius: 50%; /* World-Class Neural Shard */
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--clr-white);
    z-index: 3;
    transition: all var(--t-base);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4), 0 0 20px rgba(var(--clr-accent-primary-rgb), 0.3);
}

.arch-node:hover .arch-node__icon {
    background: var(--clr-accent-primary);
    color: var(--clr-white);
    transform: scale(1.1) rotate(-5deg);
    box-shadow: 0 0 30px rgba(var(--clr-accent-primary-rgb), 0.5);
}

.arch-node:hover .arch-node__icon svg {
    filter: drop-shadow(0 0 8px rgba(255, 255, 255, 0.8));
}

.arch-node__title {
    font-size: var(--fs-xl);
    color: var(--clr-gray-900);
}

.arch-node__desc {
    font-size: var(--fs-sm);
    color: var(--clr-gray-500);
    line-height: var(--lh-base);
    flex-grow: 1;
}

/* HELPER: Mobile Formatting */
@media (min-width: 768px) {
    .mobile-only { display: none; }
}

@media (max-width: 767px) {
    .desktop-only { display: none; }
}