/* ======================== CASE STUDY — SHARED STYLES ======================== */
/* Inherits design tokens from the main Weyuu site */

:root {
    --black: #0a0a0a;
    --white: #f0f0f0;
    --pure-white: #ffffff;
    --pure-black: #000000;
    --gray: #777;
    --gray-light: #aaa;
    --gray-dark: #555;
    --dim: #141414;
    --card: #111;
    --accent: #3b82f6;
    --accent-light: #60a5fa;
    --accent-dark: #2563eb;
    --bg-light: #e0e0e0;
    --text-dark: #1a1a1a;
    --text-mid: #444;
    --font: 'Inter', -apple-system, sans-serif;
    --transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --transition-fast: all 0.25s ease;
    --transition-smooth: all 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ======================== RESET ======================== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font);
    background: #050505;
    color: var(--white);
    line-height: 1.6;
    overflow-x: clip;
}

/* Film grain */
body::after {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 9999;
    pointer-events: none;
    opacity: 0.03;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' 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)'/%3E%3C/svg%3E");
    background-size: 180px;
}

a {
    color: inherit;
    text-decoration: none;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ======================== NAVBAR ======================== */
.cs-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1.25rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: var(--transition);
}

.cs-nav.scrolled {
    background: rgba(5, 5, 5, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.cs-nav-back {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    color: var(--gray-light);
    transition: var(--transition-fast);
}

.cs-nav-back:hover {
    color: var(--white);
}

.cs-nav-back svg {
    width: 18px;
    height: 18px;
    transition: transform 0.3s ease;
}

.cs-nav-back:hover svg {
    transform: translateX(-3px);
}

.cs-nav-logo img {
    height: 28px;
    opacity: 0.9;
}

.cs-nav-contact {
    font-size: 0.85rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    color: var(--black);
    background: var(--white);
    padding: 0.5rem 1.25rem;
    border-radius: 100px;
    transition: var(--transition-fast);
}

.cs-nav-contact:hover {
    background: var(--accent);
    color: var(--pure-white);
}

/* ======================== HERO ======================== */
.cs-hero {
    padding: 10rem 0 5rem;
    position: relative;
}

.cs-hero-label {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent-light);
    margin-bottom: 1.5rem;
}

.cs-hero h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 600;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1.25rem;
}

.cs-hero-desc {
    font-size: clamp(1rem, 1.5vw, 1.15rem);
    color: var(--gray);
    max-width: 600px;
    line-height: 1.7;
}

/* ======================== OVERVIEW ======================== */
.cs-overview {
    padding: 5rem 0;
    background: var(--bg-light);
    color: var(--text-dark);
}

.cs-overview-grid {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 4rem;
}

.cs-overview-text h2 {
    font-size: clamp(1.5rem, 2.5vw, 2rem);
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
}

.cs-overview-text p {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--text-mid);
}

.cs-sidebar {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.cs-sidebar-item {
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    padding-bottom: 1rem;
}

.cs-sidebar-label {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--gray);
    margin-bottom: 0.35rem;
}

.cs-sidebar-value {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dark);
}

.cs-sidebar-value a {
    color: var(--accent);
    transition: var(--transition-fast);
}

.cs-sidebar-value a:hover {
    color: var(--accent-dark);
}

/* ======================== CHALLENGE & SOLUTION ======================== */
.cs-challenge {
    padding: 5rem 0;
}

.cs-challenge-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.cs-block-label {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent-light);
    margin-bottom: 1rem;
}

.cs-block h3 {
    font-size: clamp(1.25rem, 2vw, 1.5rem);
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
}

.cs-block p {
    font-size: 0.95rem;
    line-height: 1.8;
    color: var(--gray);
}

.cs-block ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.cs-block ul li {
    font-size: 0.95rem;
    color: var(--gray);
    padding-left: 1.25rem;
    position: relative;
}

.cs-block ul li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent-light);
}

/* ======================== RESULTS ======================== */
.cs-results {
    padding: 5rem 0;
    background: var(--bg-light);
    color: var(--text-dark);
}

.cs-results-label {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent);
    margin-bottom: 2.5rem;
    text-align: center;
}

.cs-metrics-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    text-align: center;
}

.cs-metric-val {
    display: block;
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 600;
    letter-spacing: -0.03em;
    color: var(--text-dark);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.cs-metric-label {
    font-size: 0.8rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--gray);
}

/* ======================== TECH STACK ======================== */
.cs-tech {
    padding: 5rem 0;
}

.cs-tech-label {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent-light);
    margin-bottom: 1.5rem;
}

.cs-tech-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.cs-pill {
    font-size: 0.8rem;
    font-weight: 500;
    padding: 0.5rem 1.25rem;
    border-radius: 100px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: var(--gray-light);
    transition: var(--transition-fast);
}

.cs-pill:hover {
    border-color: var(--accent);
    color: var(--accent-light);
}

/* ======================== GALLERY ======================== */
.cs-gallery {
    padding: 5rem 0;
    background: var(--bg-light);
    color: var(--text-dark);
}

.cs-gallery-label {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent);
    margin-bottom: 2rem;
}

.cs-gallery-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.cs-gallery-placeholder {
    aspect-ratio: 16 / 10;
    background: rgba(0, 0, 0, 0.06);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    color: var(--gray);
    border: 1px dashed rgba(0, 0, 0, 0.15);
}

/* ======================== TESTIMONIAL ======================== */
.cs-testimonial {
    padding: 5rem 0;
    text-align: center;
}

.cs-testimonial blockquote {
    font-size: clamp(1.25rem, 2vw, 1.5rem);
    font-weight: 400;
    line-height: 1.7;
    color: var(--white);
    max-width: 700px;
    margin: 0 auto 1.5rem;
    font-style: italic;
}

.cs-testimonial-credit {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    align-items: center;
}

.cs-testimonial-name {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--white);
}

.cs-testimonial-role {
    font-size: 0.8rem;
    color: var(--gray);
}

/* ======================== CTA ======================== */
.cs-cta {
    padding: 5rem 0;
    background: var(--bg-light);
    color: var(--text-dark);
    text-align: center;
}

.cs-cta h2 {
    font-size: clamp(1.5rem, 3vw, 2.25rem);
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
}

.cs-cta p {
    font-size: 1rem;
    color: var(--text-mid);
    margin-bottom: 2rem;
}

.cs-cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.cs-cta-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    font-weight: 500;
    padding: 0.75rem 1.75rem;
    border-radius: 100px;
    transition: var(--transition-fast);
}

.cs-cta-btn-primary {
    background: var(--accent);
    color: var(--pure-white);
}

.cs-cta-btn-primary:hover {
    background: var(--accent-dark);
}

.cs-cta-btn-secondary {
    background: transparent;
    color: var(--text-dark);
    border: 1px solid rgba(0, 0, 0, 0.2);
}

.cs-cta-btn-secondary:hover {
    border-color: var(--accent);
    color: var(--accent);
}

/* ======================== FOOTER ======================== */
.cs-footer {
    padding: 2.5rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.cs-footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.cs-footer-left {
    font-size: 0.8rem;
    color: var(--gray);
}

.cs-footer-right {
    display: flex;
    gap: 1.5rem;
}

.cs-footer-right a {
    font-size: 0.8rem;
    color: var(--gray);
    transition: var(--transition-fast);
}

.cs-footer-right a:hover {
    color: var(--white);
}

/* ======================== SCROLL REVEAL ======================== */
.cs-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.cs-reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ======================== RESPONSIVE ======================== */

/* Tablet */
@media (max-width: 1024px) {
    .cs-overview-grid {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .cs-sidebar {
        flex-direction: row;
        flex-wrap: wrap;
        gap: 1.5rem;
    }

    .cs-sidebar-item {
        flex: 1;
        min-width: 140px;
    }

    .cs-challenge-grid {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .cs-metrics-row {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }
}

/* Mobile */
@media (max-width: 768px) {
    .container {
        padding: 0 1.25rem;
    }

    .cs-nav {
        padding: 1rem 1.25rem;
    }

    .cs-hero {
        padding: 7rem 0 3rem;
    }

    .cs-overview,
    .cs-challenge,
    .cs-results,
    .cs-tech,
    .cs-gallery,
    .cs-testimonial,
    .cs-cta {
        padding: 3.5rem 0;
    }

    .cs-sidebar {
        flex-direction: column;
    }

    .cs-sidebar-item {
        min-width: unset;
    }

    .cs-gallery-grid {
        grid-template-columns: 1fr;
    }

    .cs-cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .cs-footer-inner {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

/* Small Mobile */
@media (max-width: 480px) {
    .cs-metrics-row {
        grid-template-columns: 1fr 1fr;
        gap: 1.5rem;
    }

    .cs-hero h1 {
        font-size: 2rem;
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    .cs-reveal {
        opacity: 1;
        transform: none;
        transition: none;
    }
}