/* ============================================================
   Growth Design Lab — Shared Stylesheet
   ============================================================
   Color system derived from the GDL logo gradient:
   blue-teal (#2486AF) → green (#27AE60)
   Shared base with GDG: dark slate (#2C3E50), Inter font
   ============================================================ */

/* ── Reset & Variables ── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    /* Brand */
    --primary: #2C3E50;
    --accent-start: #2486AF;
    --accent-end: #27AE60;
    --accent: #2486AF;
    --accent-gradient: linear-gradient(135deg, #2486AF 0%, #27AE60 100%);

    /* Surfaces */
    --bg: #f3f6f5;
    --bg-white: #ffffff;
    --card-bg: #ffffff;
    --border: #e2e8f0;

    /* Text */
    --text: #2C3E50;
    --text-secondary: #343a40;
    --text-muted: #6c757d;

    /* Effects */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.07);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.1);
    --radius: 12px;
    --radius-lg: 16px;

    /* Framework colors */
    --fw-linguistic: #5B9BD5;
    --fw-technical: #6BCB77;
    --fw-scale: #8B9DAF;
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--text);
    line-height: 1.7;
    background: var(--bg);
}

/* ── Typography ── */
h1, h2, h3, h4, h5, h6 { font-weight: 600; line-height: 1.3; margin-bottom: 1rem; color: var(--text); }
h1 { font-size: 2.75rem; font-weight: 800; letter-spacing: -0.5px; }
h2 { font-size: 2rem; margin-bottom: 1.5rem; }
h3 { font-size: 1.35rem; }
h4 { font-size: 1.1rem; }
p { margin-bottom: 1rem; color: var(--text-secondary); }
a { color: var(--accent); }

.gradient-text {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline;
}

.lead { font-size: 1.2rem; font-weight: 400; color: var(--text-muted); line-height: 1.65; }

.section-label {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent);
    margin-bottom: 0.75rem;
}

/* ── Layout ── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 2rem; }
.container-narrow { max-width: 800px; margin: 0 auto; padding: 0 2rem; }
section { padding: 5rem 0; }

/* ── Header ── */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(243, 246, 245, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: box-shadow 0.3s;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 6px 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo { display: flex; align-items: center; text-decoration: none; }
.logo img { height: 70px; width: auto; }

.nav-links { display: flex; list-style: none; gap: 2rem; align-items: center; }
.nav-links a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    font-size: 0.9rem;
    transition: color 0.2s;
    position: relative;
}
.nav-links a:hover { color: var(--accent); }
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px; left: 0;
    width: 0; height: 2px;
    background: var(--accent-gradient);
    transition: width 0.3s;
}
.nav-links a:hover::after { width: 100%; }

.nav-cta {
    padding: 0.5rem 1.25rem;
    background: var(--accent-gradient);
    color: white !important;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.85rem;
    -webkit-text-fill-color: white !important;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover { opacity: 0.9; }

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text);
}

/* ── Cards ── */
.card-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1.5rem;
}
.card-grid > .card,
.card-grid > .coming-soon {
    width: calc(33.333% - 1rem);
    min-width: 300px;
    max-width: 400px;
}

.card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: transform 0.25s, box-shadow 0.25s;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border);
    text-decoration: none;
    color: inherit;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }

.card-image { height: 180px; overflow: hidden; position: relative; }
.card-image img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.4s; }
.card:hover .card-image img { transform: scale(1.05); }

.card-type-badge {
    position: absolute;
    top: 0.75rem; left: 0.75rem;
    padding: 0.25rem 0.65rem;
    border-radius: 100px;
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: white;
}

.badge-framework { background: var(--accent); }
.badge-guide { background: #3498DB; }
.badge-tool { background: #E67E22; }
.badge-podcast { background: #9B59B6; }
.badge-community { background: #E74C3C; }

.card-body { padding: 1.5rem; flex: 1; display: flex; flex-direction: column; }
.card-body h3 { font-size: 1.15rem; margin-bottom: 0.65rem; line-height: 1.35; }
.card-body p { font-size: 0.9rem; color: var(--text-muted); line-height: 1.6; flex: 1; margin-bottom: 1.25rem; }

.card-cta {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--accent);
    font-weight: 600;
    font-size: 0.85rem;
    text-decoration: none;
    transition: gap 0.2s;
}
.card-cta:hover { gap: 0.65rem; }

.arrow-icon { transition: transform 0.2s; }
.card-cta:hover .arrow-icon { transform: translateX(2px); }

/* ── Filter Tabs ── */
.filter-bar { display: flex; gap: 0.5rem; justify-content: center; flex-wrap: wrap; margin-bottom: 3rem; }
.filter-btn {
    padding: 0.45rem 1.1rem;
    border: 1.5px solid var(--border);
    border-radius: 100px;
    background: var(--bg-white);
    color: var(--text-muted);
    font-family: inherit;
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}
.filter-btn:hover { border-color: var(--accent); color: var(--accent); }
.filter-btn.active { background: var(--accent-gradient); color: white; border-color: transparent; }

/* ── Buttons ── */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.75rem;
    border-radius: 6px;
    font-family: inherit;
    font-weight: 600;
    font-size: 0.95rem;
    text-decoration: none;
    transition: all 0.2s;
    border: 2px solid transparent;
    cursor: pointer;
}
.btn-primary { background: var(--accent-gradient); color: white; }
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }
.btn-outline { background: transparent; color: white; border-color: rgba(255,255,255,0.5); }
.btn-outline:hover { border-color: white; background: rgba(255,255,255,0.1); }

/* ── Page Hero (for subpages) ── */
.page-hero {
    padding: 8rem 0 3rem;
    background: var(--bg);
}
.page-hero .section-label { margin-bottom: 1rem; }
.page-hero h1 { margin-bottom: 1rem; }
.page-hero .lead { max-width: 650px; }

/* ── Breadcrumb ── */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}
.breadcrumb a { color: var(--accent); text-decoration: none; font-weight: 500; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb span { color: var(--text-muted); }

/* ── Content blocks ── */
.content-section { background: var(--bg-white); padding: 5rem 0; }
.content-section:nth-child(even) { background: var(--bg); }
.content-section h2 { margin-bottom: 1rem; }
.content-section .lead { margin-bottom: 2rem; }

.prose { max-width: 720px; }
.prose p { font-size: 1.05rem; line-height: 1.8; margin-bottom: 1.5rem; }
.prose h2 { margin-top: 2.5rem; }
.prose h3 { margin-top: 2rem; }
.prose ul, .prose ol { margin: 1rem 0 1.5rem 1.5rem; }
.prose li { margin-bottom: 0.5rem; font-size: 1rem; color: var(--text-secondary); line-height: 1.7; }

/* ── Framework cards (3-column) ── */
.framework-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }

.framework-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 2rem;
    border: 1px solid var(--border);
    transition: all 0.25s;
    position: relative;
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    display: block;
}
.framework-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; }
.framework-card.linguistic::before { background: var(--fw-linguistic); }
.framework-card.technical::before { background: var(--fw-technical); }
.framework-card.scale::before { background: var(--fw-scale); }
.framework-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }

.framework-icon {
    width: 52px; height: 52px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.25rem;
}
.linguistic .framework-icon { background: rgba(91,155,213,0.12); }
.technical .framework-icon { background: rgba(107,203,119,0.12); }
.scale .framework-icon { background: rgba(139,157,175,0.12); }

.framework-card h3 { font-size: 1.2rem; margin-bottom: 0.75rem; }
.framework-card > p { font-size: 0.9rem; color: var(--text-muted); line-height: 1.6; }

.framework-risks { list-style: none; margin-top: 1.25rem; padding: 0; }
.framework-risks li {
    padding: 0.45rem 0 0.45rem 1.4rem;
    position: relative;
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
}
.framework-risks li::before {
    content: '';
    position: absolute;
    left: 0; top: 0.75rem;
    width: 6px; height: 6px;
    border-radius: 50%;
}
.linguistic .framework-risks li::before { background: var(--fw-linguistic); }
.technical .framework-risks li::before { background: var(--fw-technical); }
.scale .framework-risks li::before { background: var(--fw-scale); }

/* ── Data bars ── */
.data-bars { margin-top: 1.5rem; }
.data-bar-row {
    display: grid;
    grid-template-columns: 140px 1fr 60px;
    gap: 1rem;
    align-items: center;
    margin-bottom: 0.75rem;
}
.data-bar-label { font-size: 0.8rem; font-weight: 600; color: var(--text); }
.data-bar-track { height: 24px; background: rgba(36,134,175,0.08); border-radius: 12px; overflow: hidden; }
.data-bar-fill { height: 100%; border-radius: 12px; background: var(--accent-gradient); transition: width 1s ease; }
.data-bar-fill.secondary { background: linear-gradient(135deg, #5B9BD5, #3498DB); }
.data-bar-fill.tertiary { background: linear-gradient(135deg, #E67E22, #F39C12); }
.data-bar-fill.quaternary { background: linear-gradient(135deg, #95A5A6, #BDC3C7); }
.data-bar-value { font-size: 0.8rem; font-weight: 700; color: var(--accent); text-align: right; }

/* ── Callout boxes ── */
.callout {
    background: linear-gradient(135deg, rgba(36,134,175,0.06), rgba(39,174,96,0.06));
    border: 1px solid rgba(36,134,175,0.15);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
}

/* ── Podcast section ── */
.podcast-section { background: var(--primary); color: white; padding: 4rem 0; }
.podcast-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; align-items: center; }
.podcast-inner h2 { color: white; }
.podcast-inner p { color: rgba(255,255,255,0.8); }

.podcast-links { display: flex; gap: 0.75rem; flex-wrap: wrap; margin-top: 1.5rem; }
.podcast-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.25rem;
    border: 1.5px solid rgba(255,255,255,0.25);
    border-radius: 100px;
    color: white;
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.2s;
}
.podcast-link:hover { border-color: var(--accent-end); background: rgba(36,134,175,0.2); }

.podcast-art {
    width: 280px; height: 280px;
    border-radius: 20px;
    background: var(--accent-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    position: relative;
    margin: 0 auto;
}
.podcast-art::before {
    content: '';
    position: absolute;
    inset: 4px;
    border: 2px solid rgba(255,255,255,0.15);
    border-radius: 17px;
}
.podcast-art-text { text-align: center; color: white; }
.podcast-art-text .title { font-size: 1.5rem; font-weight: 800; line-height: 1.2; margin-bottom: 0.35rem; }
.podcast-art-text .subtitle { font-size: 0.7rem; font-weight: 500; letter-spacing: 0.12em; text-transform: uppercase; opacity: 0.8; }

/* ── Coming-soon badge ── */
.coming-soon { position: relative; }
.coming-soon::after {
    content: 'Coming soon';
    position: absolute;
    top: 0.75rem; right: 0.75rem;
    padding: 0.2rem 0.6rem;
    background: rgba(44,62,80,0.85);
    color: white;
    border-radius: 100px;
    font-size: 0.6rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    z-index: 5;
}
.coming-soon .card-image img { filter: grayscale(40%); }

/* ── CTA band ── */
.cta-band { background: var(--accent-gradient); padding: 4rem 0; text-align: center; }
.cta-band h2 { color: white; margin-bottom: 0.75rem; }
.cta-band p { color: rgba(255,255,255,0.85); max-width: 550px; margin: 0 auto 2rem; font-size: 1.05rem; }
.cta-band .btn-row { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

/* ── Footer ── */
footer { background: var(--primary); color: white; padding: 3rem 0 2rem; }
.footer-inner { display: flex; justify-content: space-between; align-items: flex-start; flex-wrap: wrap; gap: 2rem; }
.footer-brand p { color: rgba(255,255,255,0.65); font-size: 0.9rem; max-width: 360px; }
.footer-brand h4 { color: white; margin-bottom: 0.5rem; }
.footer-links { display: flex; gap: 3rem; }
.footer-col h4 { color: var(--accent-end); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.1em; margin-bottom: 0.75rem; }
.footer-col a { display: block; color: rgba(255,255,255,0.7); text-decoration: none; font-size: 0.9rem; line-height: 2; transition: color 0.2s; }
.footer-col a:hover { color: var(--accent-end); }

.footer-bottom {
    margin-top: 2.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}
.footer-bottom p { color: rgba(255,255,255,0.45); font-size: 0.8rem; margin: 0; }

.gdg-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.65rem 1.5rem;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 100px;
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s;
}
.gdg-badge:hover { border-color: rgba(184,134,11,0.5); color: rgba(255,255,255,0.9); }

.gdg-gold {
    background: linear-gradient(135deg, #B8860B 0%, #D4AF37 50%, #B8860B 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 600;
}

/* ── Detail page risk grid ── */
.risk-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 1.25rem; }
.risk-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 1.75rem;
    border: 1px solid var(--border);
    transition: box-shadow 0.2s;
}
.risk-card:hover { box-shadow: var(--shadow-md); }
.risk-card h4 { margin-bottom: 0.5rem; }
.risk-card p { font-size: 0.9rem; color: var(--text-muted); margin: 0; line-height: 1.6; }
.risk-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px; height: 28px;
    border-radius: 8px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: white;
}

/* ── Animations ── */
@keyframes fadeInUp { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: translateY(0); } }
.fade-in { animation: fadeInUp 0.5s ease-out; }

/* ── Responsive ── */
@media (max-width: 900px) {
    .framework-grid { grid-template-columns: 1fr; }
    .podcast-inner { grid-template-columns: 1fr; text-align: center; }
    .podcast-links { justify-content: center; }
    .podcast-art { order: -1; }
}
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    .card-grid > .card,
    .card-grid > .coming-soon { width: 100%; max-width: 100%; }
    .mobile-menu-btn { display: block; }
    .nav-links {
        display: none;
        position: absolute;
        top: 100%; left: 0; right: 0;
        background: var(--bg-white);
        flex-direction: column;
        padding: 1.5rem 2rem;
        box-shadow: var(--shadow-md);
        gap: 1rem;
    }
    .nav-links.active { display: flex; }
    section { padding: 3.5rem 0; }
    .container { padding: 0 1.25rem; }
    .container-narrow { padding: 0 1.25rem; }
    .footer-links { flex-direction: column; gap: 1.5rem; }
    .footer-inner { flex-direction: column; }
    .data-bar-row { grid-template-columns: 100px 1fr 50px; }
    .risk-grid { grid-template-columns: 1fr; }
}