/* ── DESIGN SYSTEM: Bold Minimal (Concept D) ── */
:root {
    --bg:           #ffffff;
    --bg-alt:       #f9fafb;
    --text:         #111827;
    --text-2:       #374151;
    --text-3:       #6b7280;
    --blue:         #2563eb;
    --blue-dk:      #1d4ed8;
    --blue-lt:      #eff6ff;
    --border:       #e5e7eb;
    --border-lt:    #f3f4f6;

    /* Legacy aliases kept so inner pages don't break */
    --bg-primary:     var(--bg);
    --bg-secondary:   var(--bg-alt);
    --bg-tertiary:    var(--bg-alt);
    --bg-card:        var(--bg);
    --border-color:   var(--border);
    --text-primary:   var(--text);
    --text-secondary: var(--text-2);
    --text-muted:     var(--text-3);
    --accent-primary: var(--blue);
    --accent-dark:    var(--blue-dk);
    --accent-light:   var(--blue-lt);
    --accent-secondary: #3b82f6;
    --shadow-sm:      0 1px 3px rgba(0,0,0,0.06);
    --shadow-md:      0 4px 12px rgba(0,0,0,0.07);
    --shadow-lg:      0 10px 30px rgba(0,0,0,0.08);
    --shadow-card:    0 1px 4px rgba(0,0,0,0.06);
    --shadow-card-hover: 0 6px 24px rgba(0,0,0,0.1);
}

/* ── RESET ── */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; }
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text);
    background: var(--bg);
    overflow-x: hidden;
}
img { max-width: 100%; }

/* ── LAYOUT ── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 28px; }

/* ── NAVBAR ── */
.navbar {
    background: rgba(255,255,255,0.97);
    backdrop-filter: blur(12px);
    position: fixed;
    top: 0; width: 100%;
    z-index: 1000;
    border-bottom: 1px solid var(--border-lt);
}
.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 28px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}
.nav-logo h1 {
    font-size: 1.25rem;
    font-weight: 900;
    color: var(--text);
    letter-spacing: -0.04em;
}
.nav-menu { display:flex; list-style:none; gap:2.5rem; align-items:center; }
.nav-link {
    text-decoration: none;
    color: var(--text-3);
    font-size: 0.875rem;
    font-weight: 500;
    transition: color 0.2s;
    padding: 6px 0;
}
.nav-link:hover, .nav-link.active { color: var(--text); }
.nav-link.active { font-weight: 600; }
.nav-toggle { display:none; flex-direction:column; cursor:pointer; gap:5px; }
.bar { width:22px; height:2px; background:var(--text); border-radius:2px; transition:0.3s; }

/* ── PAGE HERO (inner pages) ── */
.page-hero {
    background: var(--bg);
    padding: 130px 0 72px;
    border-bottom: 1px solid var(--border-lt);
}
.page-title {
    font-size: 3rem;
    font-weight: 900;
    color: var(--text);
    letter-spacing: -0.04em;
    line-height: 1.1;
    margin-bottom: 1rem;
}
.page-subtitle {
    font-size: 1.1rem;
    color: var(--text-3);
    max-width: 540px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ── SECTIONS ── */
section { padding: 90px 0; }
.section-header { text-align:center; margin-bottom: 3.5rem; }
.section-tag {
    display: block;
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: var(--blue);
    margin-bottom: 0.75rem;
}
.section-title {
    font-size: 2.4rem;
    font-weight: 900;
    color: var(--text);
    letter-spacing: -0.04em;
    line-height: 1.1;
    margin-bottom: 0.75rem;
}
.section-subtitle {
    font-size: 1.05rem;
    color: var(--text-3);
    max-width: 540px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ── BUTTONS ── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 13px 26px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.925rem;
    transition: all 0.2s ease;
    border: none;
    cursor: pointer;
}
.btn-primary {
    background: var(--blue);
    color: #fff;
}
.btn-primary:hover { background: var(--blue-dk); transform: translateY(-1px); }
.btn-outline {
    background: transparent;
    color: var(--blue);
    border: 1.5px solid var(--blue);
}
.btn-outline:hover { background: var(--blue); color: #fff; }
.btn-white { background: #fff; color: var(--blue); }
.btn-white:hover { background: #f0f6ff; }

/* ── CARDS ── */
.card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 2rem;
    transition: all 0.25s ease;
}
.card:hover { transform: translateY(-4px); border-color: #d1d5db; box-shadow: var(--shadow-card-hover); }
.card-icon {
    width: 48px; height: 48px;
    background: var(--blue-lt);
    border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    margin-bottom: 1.25rem;
}
.card-icon i { font-size: 1.25rem; color: var(--blue); }
.card h3 { font-size: 1.1rem; font-weight: 700; color: var(--text); margin-bottom: 0.6rem; }
.card p { color: var(--text-3); line-height: 1.7; font-size: 0.95rem; }

/* ── CTA SECTION ── */
.cta-section { background: var(--blue); }
.cta-content { text-align: center; padding: 20px 0; }
.cta-content h2 { font-size: 2.2rem; font-weight: 900; color: #fff; letter-spacing: -0.04em; margin-bottom: 0.75rem; }
.cta-content p { font-size: 1.05rem; color: rgba(255,255,255,0.85); margin-bottom: 2rem; }
.cta-buttons { display:flex; gap:1rem; justify-content:center; flex-wrap:wrap; }

/* ── FOOTER ── */
.footer { background: #111827; padding: 64px 0 32px; }
.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}
.footer-brand h3 { font-size: 1.2rem; font-weight: 900; color: #fff; letter-spacing: -0.03em; margin-bottom: 0.75rem; }
.footer-brand p { color: #6b7280; line-height: 1.7; font-size: 0.9rem; }
.footer-section h4 { font-size: 0.72rem; font-weight: 800; color: #9ca3af; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 1.25rem; }
.footer-section ul { list-style: none; }
.footer-section li { margin-bottom: 0.5rem; }
.footer-section a { color: #6b7280; text-decoration: none; font-size: 0.9rem; transition: color 0.2s; }
.footer-section a:hover { color: #fff; }
.footer-contact p { color: #6b7280; margin-bottom: 0.5rem; display:flex; align-items:center; gap:10px; font-size: 0.9rem; }
.footer-contact i { color: #9ca3af; width:16px; }
.footer-bottom { padding-top: 2rem; border-top: 1px solid #1f2937; text-align: center; }
.footer-bottom p { color: #4b5563; font-size: 0.875rem; }

/* ── FADE-IN ANIMATION ── */
.fade-in { opacity:0; transform: translateY(18px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity:1; transform: translateY(0); }

/* ── ILLUSTRATION TREATMENT ── */
.illus { filter: grayscale(20%) saturate(0.65); }

/* ── RESPONSIVE ── */
@media (max-width: 1024px) {
    .page-title { font-size: 2.25rem; }
    .section-title { font-size: 2rem; }
    .footer-content { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 64px; left:0; right:0;
        background: #fff;
        flex-direction: column;
        padding: 1.5rem 28px;
        gap: 1rem;
        border-bottom: 1px solid var(--border-lt);
        box-shadow: var(--shadow-md);
    }
    .nav-menu.active { display: flex; }
    .nav-toggle { display: flex; }
    .page-hero { padding: 110px 0 60px; }
    .page-title { font-size: 1.875rem; }
    .section-title { font-size: 1.6rem; }
    section { padding: 64px 0; }
    .footer-content { grid-template-columns: 1fr; gap: 2rem; }
}