/* =====================================================
   SHARED STYLES — Mukul Dewangan Portfolio
   Used by: index.html, case-study-*.html, teardowns.html
   ===================================================== */

/* ===== TOKENS ===== */
:root {
    --bg:          #F3EDE2;
    --bg-alt:      #EDE6D8;
    --bg-dark:     #0F0F0D;
    --surface:     #E8E1D5;
    --text:        #0D0C09;
    --text-muted:  #6B655C;
    --text-light:  #9B9489;
    --teal:        #1C5E5E;
    --teal-light:  #2A7A7A;
    --accent:      #C05A1A;
    --accent-hover:#A34A12;
    --border:      rgba(13,12,9,0.11);
    --border-dark: rgba(243,237,226,0.10);

    --font-display: 'Cormorant', serif;
    --font-body:    'DM Sans', sans-serif;

    --r-sm: 3px;
    --r-md: 8px;
    --r-lg: 16px;
}

/* ===== RESET ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    font-weight: 300;
    -webkit-font-smoothing: antialiased;
}

/* ===== GRAIN TEXTURE ===== */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.035'/%3E%3C/svg%3E");
    background-size: 180px 180px;
    pointer-events: none;
    z-index: 999;
}

/* ===== NAV — Light variant (index + case studies) ===== */
nav {
    position: fixed;
    inset: 0 0 auto 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 3rem;
    border-bottom: 1px solid var(--border);
}
nav.nav-light {
    background: rgba(243,237,226,0.88);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
}
/* Dark variant for dark-bg pages (teardowns) */
nav.nav-dark {
    background: rgba(15,15,13,0.90);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom-color: var(--border-dark);
}

/* Nav logo */
.nav-logo {
    font-family: var(--font-display);
    font-size: 1.2rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    color: var(--text);
    text-decoration: none;
}

/* Nav back link (sub-pages) */
.nav-back {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.75rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
}
.nav-dark .nav-back { color: rgba(243,237,226,0.50); }
.nav-back:hover { color: var(--text); }
.nav-dark .nav-back:hover { color: #F3EDE2; }
.nav-back .arrow { transition: transform 0.2s; }
.nav-back:hover .arrow { transform: translateX(-4px); }

/* Nav links */
.nav-links {
    display: flex;
    gap: 2.5rem;
    list-style: none;
}
.nav-links a {
    font-size: 0.75rem;
    font-weight: 400;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--text); }
.nav-dark .nav-links a { color: rgba(243,237,226,0.40); }
.nav-dark .nav-links a:hover,
.nav-dark .nav-links a.active { color: #F3EDE2; }
.nav-meta {
    font-family: var(--font-display);
    font-size: 0.95rem;
    font-style: italic;
    color: var(--text-muted);
}
.nav-dark .nav-meta { color: rgba(243,237,226,0.45); }

/* ===== SCROLL REVEAL ANIMATIONS ===== */
@media (prefers-reduced-motion: no-preference) {
    .reveal {
        opacity: 0;
        transform: translateY(24px);
        transition: opacity 0.7s ease, transform 0.7s ease;
    }
    .reveal.in { opacity: 1; transform: none; }
    .reveal-d1 { transition-delay: 0.10s; }
    .reveal-d2 { transition-delay: 0.22s; }
    .reveal-d3 { transition-delay: 0.34s; }
}

/* ===== SHARED UTILITY ===== */
.section-label {
    font-size: 0.68rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--teal);
    font-weight: 500;
    margin-bottom: 0.75rem;
}

/* ===== RESPONSIVE NAV ===== */
@media (max-width: 1024px) {
    nav { padding: 1.25rem 2rem; }
}
@media (max-width: 640px) {
    nav { padding: 1rem 1.5rem; }
    .nav-links { gap: 1.5rem; }
}