/* ===================================================
   SANGYUG SOLAR — CASE STUDIES
   =================================================== */

/* Lucide icon defaults */
[data-lucide] {
    width: 1em;
    height: 1em;
    stroke: currentColor;
    stroke-width: 2;
    fill: none;
    vertical-align: -0.125em;
    display: inline-block;
}

:root {
    --hue: 220;
    --bg-0: hsl(var(--hue) 25% 7%);
    --bg-1: hsl(var(--hue) 20% 11%);
    --bg-2: hsl(var(--hue) 18% 16%);
    --bg-3: hsl(var(--hue) 14% 22%);
    --glass: hsla(var(--hue) 20% 14% / .65);
    --glass-border: hsla(var(--hue) 40% 50% / .12);
    --accent: hsl(210 100% 56%);
    --accent-soft: hsl(210 80% 68%);
    --accent-glow: hsla(210 100% 60% / .25);
    --green: hsl(150 60% 48%);
    --green-glow: hsla(150 60% 48% / .2);
    --red: hsl(0 72% 56%);
    --amber: hsl(38 92% 60%);
    --text-0: hsl(0 0% 96%);
    --text-1: hsl(var(--hue) 10% 72%);
    --text-2: hsl(var(--hue) 8% 52%);
    --border: hsl(var(--hue) 14% 20%);
    --card: hsl(var(--hue) 20% 12%);
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 22px;
    --shadow-sm: 0 2px 8px hsla(0 0% 0% / .2);
    --shadow-md: 0 8px 30px hsla(0 0% 0% / .28);
    --shadow-lg: 0 16px 60px hsla(0 0% 0% / .35);
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background: var(--bg-0);
    color: var(--text-0);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    min-height: 100vh;
}

img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; }
a { text-decoration: none; color: inherit; }

/* ── NAV ── */
.cs-nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    background: hsla(var(--hue) 25% 7% / .85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}
.cs-nav-inner {
    max-width: 1200px; margin: 0 auto;
    padding: 0 24px; height: 64px;
    display: flex; align-items: center; justify-content: space-between;
}
.cs-nav-logo { height: 32px; }
.cs-nav-links { display: flex; gap: 8px; }
.cs-nav-link {
    padding: 7px 18px; border-radius: 8px;
    font-size: .85rem; font-weight: 600;
    color: var(--text-1); transition: all .2s;
}
.cs-nav-link:hover { color: var(--text-0); background: var(--bg-2); }
.cs-nav-link.active {
    color: var(--accent); background: rgba(56, 189, 248, .08);
}

/* ── HERO ── */
.cs-hero {
    padding: 140px 24px 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.cs-hero::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; bottom: 0;
    background:
        radial-gradient(ellipse 600px 400px at 30% 20%, hsla(210 100% 50% / .06), transparent),
        radial-gradient(ellipse 500px 300px at 70% 60%, hsla(150 60% 48% / .04), transparent);
    pointer-events: none;
}
.cs-hero-tag {
    display: inline-block;
    font-size: .75rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 1.5px;
    color: var(--accent); margin-bottom: 16px;
}
.cs-hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.8rem);
    font-weight: 800; line-height: 1.1;
    margin-bottom: 16px;
}
.cs-hero p {
    font-size: 1.1rem; color: var(--text-1);
    max-width: 520px; margin: 0 auto;
}

/* ── STATS ── */
.cs-stats {
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    background: var(--bg-1);
}
.cs-stats-inner {
    max-width: 1200px; margin: 0 auto;
    padding: 40px 24px;
    display: grid; grid-template-columns: repeat(4, 1fr);
    gap: 24px; text-align: center;
}
.cs-stat-num {
    display: block;
    font-size: 2.4rem; font-weight: 800;
    color: var(--accent);
    line-height: 1;
}
.cs-stat-label {
    font-size: .8rem; color: var(--text-2);
    text-transform: uppercase; letter-spacing: .5px;
    font-weight: 600; margin-top: 6px; display: block;
}

/* ── FILTERS ── */
.cs-filters {
    padding: 32px 24px 0;
}
.cs-filters-inner {
    max-width: 1200px; margin: 0 auto;
    display: flex; gap: 8px; flex-wrap: wrap;
}
.cs-filter {
    padding: 8px 20px; border-radius: 8px;
    border: 1.5px solid var(--border);
    background: transparent; color: var(--text-1);
    font-size: .82rem; font-weight: 600;
    transition: all .2s;
}
.cs-filter:hover { border-color: var(--text-2); color: var(--text-0); }
.cs-filter.active {
    background: var(--accent); color: #fff;
    border-color: var(--accent);
}

/* ── GRID ── */
.cs-grid-section {
    padding: 32px 24px 60px;
}
.cs-grid {
    max-width: 1200px; margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 24px;
}

/* ── CARD ── */
.cs-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: transform .25s, box-shadow .25s;
    cursor: pointer;
    display: flex; flex-direction: column;
}
.cs-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}
.cs-card-img {
    width: 100%; height: 220px;
    object-fit: cover;
    background: var(--bg-2);
}
.cs-card-body {
    padding: 20px; flex: 1;
    display: flex; flex-direction: column;
}
.cs-card-tags {
    display: flex; gap: 6px; flex-wrap: wrap;
    margin-bottom: 12px;
}
.cs-card-tag {
    font-size: .65rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: .5px;
    padding: 3px 10px; border-radius: 6px;
}
.cs-card-tag.residential {
    color: var(--green); background: rgba(59, 186, 120, .1);
    border: 1px solid rgba(59, 186, 120, .2);
}
.cs-card-tag.commercial {
    color: var(--accent); background: rgba(56, 189, 248, .1);
    border: 1px solid rgba(56, 189, 248, .2);
}
.cs-card-tag.agricultural {
    color: var(--amber); background: rgba(245, 158, 11, .1);
    border: 1px solid rgba(245, 158, 11, .2);
}
.cs-card-title {
    font-size: 1.1rem; font-weight: 700;
    margin-bottom: 6px; line-height: 1.3;
}
.cs-card-location {
    font-size: .8rem; color: var(--text-2);
    margin-bottom: 12px;
    display: flex; align-items: center; gap: 6px;
}
.cs-card-location i { font-size: .7rem; }
.cs-card-excerpt {
    font-size: .85rem; color: var(--text-1);
    margin-bottom: 16px; flex: 1;
    display: -webkit-box; -webkit-line-clamp: 3;
    -webkit-box-orient: vertical; overflow: hidden;
}
.cs-card-specs {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 8px; padding-top: 14px;
    border-top: 1px solid var(--border);
}
.cs-card-spec {
    display: flex; flex-direction: column;
}
.cs-card-spec-label {
    font-size: .62rem; font-weight: 600;
    text-transform: uppercase; letter-spacing: .4px;
    color: var(--text-2);
}
.cs-card-spec-val {
    font-size: .85rem; font-weight: 700; color: var(--text-0);
}
.cs-card-read {
    display: flex; align-items: center; gap: 6px;
    margin-top: 14px; padding-top: 14px;
    border-top: 1px solid var(--border);
    font-size: .82rem; font-weight: 600;
    color: var(--accent); transition: gap .2s;
}
.cs-card:hover .cs-card-read { gap: 10px; }

/* ── DETAIL OVERLAY ── */
.cs-detail-overlay {
    position: fixed; inset: 0; z-index: 200;
    background: hsla(var(--hue) 25% 5% / .8);
    backdrop-filter: blur(8px);
    display: flex; align-items: flex-start; justify-content: center;
    padding: 80px 24px 40px;
    overflow-y: auto;
    opacity: 0; pointer-events: none;
    transition: opacity .3s;
}
.cs-detail-overlay.open {
    opacity: 1; pointer-events: auto;
}
.cs-detail {
    background: var(--bg-1);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    max-width: 800px; width: 100%;
    position: relative;
    transform: translateY(20px);
    transition: transform .3s;
}
.cs-detail-overlay.open .cs-detail {
    transform: translateY(0);
}
.cs-detail-close {
    position: absolute; top: 16px; right: 16px;
    width: 40px; height: 40px;
    border-radius: 50%; border: 1px solid var(--border);
    background: var(--bg-2); color: var(--text-1);
    font-size: 1rem; z-index: 5;
    display: flex; align-items: center; justify-content: center;
    transition: all .2s;
}
.cs-detail-close:hover { color: var(--text-0); border-color: var(--text-2); }

.cs-detail-hero-img {
    width: 100%; height: 320px;
    object-fit: cover;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}
.cs-detail-content {
    padding: 32px;
}
.cs-detail-tags {
    display: flex; gap: 6px; flex-wrap: wrap;
    margin-bottom: 16px;
}
.cs-detail-title {
    font-size: 1.6rem; font-weight: 800;
    margin-bottom: 6px; line-height: 1.2;
}
.cs-detail-location {
    font-size: .85rem; color: var(--text-2);
    display: flex; align-items: center; gap: 6px;
    margin-bottom: 24px;
}
.cs-detail-stats {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 12px; margin-bottom: 28px;
}
.cs-detail-stat {
    background: var(--bg-2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
}
.cs-detail-stat-label {
    font-size: .62rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: .5px;
    color: var(--text-2); margin-bottom: 4px;
}
.cs-detail-stat-val {
    font-size: 1.15rem; font-weight: 800;
}
.cs-detail-stat-val.accent { color: var(--accent); }
.cs-detail-stat-val.green { color: var(--green); }
.cs-detail-stat-val.amber { color: var(--amber); }

.cs-detail-section {
    margin-bottom: 24px;
}
.cs-detail-section h3 {
    font-size: .95rem; font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-0);
}
.cs-detail-section p {
    font-size: .88rem; color: var(--text-1);
    line-height: 1.7;
}
.cs-detail-section ul {
    list-style: none; padding: 0;
}
.cs-detail-section li {
    font-size: .88rem; color: var(--text-1);
    padding: 6px 0;
    display: flex; align-items: flex-start; gap: 10px;
}
.cs-detail-section li i {
    color: var(--green); margin-top: 4px; flex-shrink: 0;
    font-size: .7rem;
}
.cs-detail-quote {
    background: var(--bg-2);
    border-left: 3px solid var(--accent);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    padding: 16px 20px;
    margin-top: 24px;
}
.cs-detail-quote p {
    font-size: .9rem; color: var(--text-1);
    font-style: italic; line-height: 1.7;
}
.cs-detail-quote cite {
    display: block; margin-top: 8px;
    font-size: .78rem; color: var(--text-2);
    font-style: normal; font-weight: 600;
}

/* ── CTA ── */
.cs-cta {
    background: var(--bg-1);
    border-top: 1px solid var(--border);
    padding: 64px 24px;
    text-align: center;
}
.cs-cta-inner { max-width: 560px; margin: 0 auto; }
.cs-cta h2 {
    font-size: 1.8rem; font-weight: 800;
    margin-bottom: 10px;
}
.cs-cta p {
    font-size: .95rem; color: var(--text-1);
    margin-bottom: 28px;
}
.cs-cta-btns {
    display: flex; gap: 12px; justify-content: center;
    flex-wrap: wrap;
}
.cs-cta-btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 12px 28px; border-radius: 10px;
    font-size: .9rem; font-weight: 700;
    transition: all .2s;
}
.cs-cta-btn.primary {
    background: var(--accent); color: #fff;
}
.cs-cta-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(56, 189, 248, .25);
}
.cs-cta-btn.secondary {
    background: transparent; color: var(--green);
    border: 1.5px solid rgba(59, 186, 120, .3);
}
.cs-cta-btn.secondary:hover {
    background: rgba(59, 186, 120, .08);
    transform: translateY(-2px);
}

/* ── FOOTER ── */
.cs-footer {
    border-top: 1px solid var(--border);
    padding: 48px 24px 0;
}
.cs-footer-inner {
    max-width: 1200px; margin: 0 auto;
    display: grid; grid-template-columns: 2fr 1fr 1fr;
    gap: 40px; padding-bottom: 40px;
}
.cs-footer-logo { height: 28px; margin-bottom: 12px; }
.cs-footer-brand p {
    font-size: .82rem; color: var(--text-2);
    max-width: 280px;
}
.cs-footer-col h4 {
    font-size: .75rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: .8px;
    color: var(--text-2); margin-bottom: 12px;
}
.cs-footer-col a {
    display: block; font-size: .85rem;
    color: var(--text-1); padding: 4px 0;
    transition: color .2s;
}
.cs-footer-col a:hover { color: var(--accent); }
.cs-footer-bottom {
    border-top: 1px solid var(--border);
    padding: 20px 0;
    text-align: center;
    font-size: .75rem; color: var(--text-2);
    max-width: 1200px; margin: 0 auto;
}

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
    .cs-stats-inner { grid-template-columns: repeat(2, 1fr); gap: 20px; }
    .cs-grid { grid-template-columns: 1fr; }
    .cs-footer-inner { grid-template-columns: 1fr; gap: 28px; }
    .cs-detail-hero-img { height: 200px; }
    .cs-detail-content { padding: 20px; }
    .cs-detail-title { font-size: 1.3rem; }
    .cs-detail-stats { grid-template-columns: repeat(2, 1fr); }
    .cs-nav-link { padding: 6px 12px; font-size: .78rem; }
}
@media (max-width: 480px) {
    .cs-hero { padding: 120px 16px 60px; }
    .cs-hero h1 { font-size: 2rem; }
    .cs-stats-inner { grid-template-columns: 1fr 1fr; gap: 16px; padding: 28px 16px; }
    .cs-stat-num { font-size: 1.8rem; }
    .cs-card-img { height: 180px; }
    .cs-detail-overlay { padding: 64px 12px 24px; }
}