/* ===========================
   DESIGN SYSTEM — CUBE‑16
   =========================== */

/* --- VARIABLES --- */
:root {
    --color-bg: #0b0d10;
    --color-bg-alt: #0f1115;
    --color-bg-soft: #1a1d22;

    --color-text: #e6f1ff;
    --color-text-soft: #c9d4e2;

    --color-blue: #008cff;
    --color-purple: #9b4dff;

    --color-border: rgba(255,255,255,0.08);
    --color-border-strong: rgba(255,255,255,0.15);

    --color-glass: rgba(255,255,255,0.03);

    --shadow-glow: 0 0 22px rgba(0,140,255,0.55);
    --shadow-glow-strong: 0 0 32px rgba(0,140,255,0.85);

    --radius-s: 6px;
    --radius-m: 12px;
    --radius-l: 18px;

    --space-xs: 4px;
    --space-s: 8px;
    --space-m: 16px;
    --space-l: 24px;
    --space-xl: 40px;

    --max-width: 1200px;
}

/* --- RESET & TYPO --- */
*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: var(--color-bg);
    color: var(--color-text);
    font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
}

h1, h2, h3, h4 {
    margin: 0 0 var(--space-m);
    font-weight: 600;
    letter-spacing: 0.03em;
}

h1 { font-size: 2.4rem; }
h2 { font-size: 1.8rem; }
h3 { font-size: 1.4rem; }

p { margin: 0 0 var(--space-m); }

a {
    color: var(--color-blue);
    text-decoration: none;
    transition: 0.25s;
}

a:hover {
    color: var(--color-purple);
}

/* --- LAYOUT --- */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
}

.section {
    padding: 60px 0;
}

.section-dark {
    background: radial-gradient(circle at top, var(--color-bg-soft), var(--color-bg));
}

.section-alt {
    background: linear-gradient(135deg, var(--color-bg), var(--color-bg-alt));
}

/* --- BUTTONS --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 22px;
    border-radius: 999px;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: 0.25s;
    border: 1px solid var(--color-border-strong);
    background: linear-gradient(135deg, #14171c, #1a1d22);
    color: var(--color-text);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-blue), var(--color-purple));
    border-color: transparent;
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    box-shadow: var(--shadow-glow-strong);
    transform: translateY(-1px);
}

.btn-ghost {
    background: transparent;
    border-color: var(--color-border-strong);
}

.btn-ghost:hover {
    background: rgba(255,255,255,0.04);
}

/* --- CARDS --- */
.card {
    background: radial-gradient(circle at top left, rgba(0,140,255,0.18), rgba(0,0,0,0.9));
    border-radius: var(--radius-l);
    padding: var(--space-l);
    border: 1px solid var(--color-border);
    box-shadow: 0 18px 40px rgba(0,0,0,0.7);
    backdrop-filter: blur(8px);
}

.card-soft {
    background: var(--color-glass);
    border-radius: var(--radius-m);
    padding: var(--space-m);
    border: 1px solid var(--color-border);
}

/* --- HERO --- */
.hero {
    padding: 80px 0 60px;
    background: radial-gradient(circle at top, rgba(0,140,255,0.35), var(--color-bg));
}

.hero-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-xl);
}

.hero-title {
    font-size: 2.6rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.hero-subtitle {
    font-size: 1.1rem;
    color: var(--color-text-soft);
    max-width: 480px;
}

.hero-actions {
    margin-top: var(--space-m);
    display: flex;
    gap: var(--space-m);
}

/* --- FOOTER --- */
.cube16-footer {
    padding: var(--space-l) var(--space-xl);
    background: var(--color-bg);
    border-top: 1px solid var(--color-border);
    font-size: 0.85rem;
    color: #8f9bb0;
    text-align: center;
}

/* --- UTILITIES --- */
.text-center { text-align: center; }
.text-right  { text-align: right; }

.mt-s { margin-top: var(--space-s); }
.mt-m { margin-top: var(--space-m); }
.mt-l { margin-top: var(--space-l); }
.mt-compact { margin-top: 8px; }
.ml-button-gap { margin-left: 10px; }

.mb-s { margin-bottom: var(--space-s); }
.mb-m { margin-bottom: var(--space-m); }
.mb-l { margin-bottom: var(--space-l); }

.text-soft { color: var(--color-text-soft); }

.revision-note {
    margin-top: 8px;
    font-size: 0.78rem;
    opacity: 0.7;
}

.hero-actions-center { justify-content: center; }

.hero-subtitle-narrow {
    max-width: 760px;
    margin: 0 auto;
}

.hero-image-compact {
    max-width: 50%;
    border-radius: 12px;
}

.is-hidden { display: none; }

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-xl);
}

.articles-hero {
    padding-bottom: 48px;
}

.articles-layout {
    display: grid;
    grid-template-columns: minmax(230px, 320px) minmax(0, 1fr);
    gap: var(--space-xl);
    align-items: start;
}

.article-index {
    position: sticky;
    top: 110px;
    background: rgba(15, 17, 21, 0.72);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-m);
    padding: var(--space-l);
}

.article-index h2 {
    font-size: 1.2rem;
}

.article-card {
    display: grid;
    gap: 6px;
    padding: var(--space-m) 0;
    color: var(--color-text-soft);
    border-top: 1px solid var(--color-border);
}

.article-card:hover {
    color: var(--color-text);
}

.article-card strong {
    display: block;
    color: var(--color-text);
    font-size: 0.98rem;
    line-height: 1.35;
}

.article-card-date,
.article-meta,
.article-language-note {
    color: #8f9bb0;
    font-size: 0.86rem;
}

.article-feed {
    display: grid;
    gap: var(--space-xl);
}

.article-entry {
    background: rgba(255,255,255,0.03);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-m);
    padding: clamp(22px, 4vw, 48px);
}

.article-entry h1 {
    margin-bottom: var(--space-m);
    font-size: clamp(1.65rem, 2.7vw, 2.35rem);
    letter-spacing: 0;
    line-height: 1.14;
    text-transform: none;
}

.article-entry h2 {
    font-size: clamp(1.35rem, 2.1vw, 1.8rem);
    letter-spacing: 0;
    line-height: 1.2;
    margin-top: var(--space-xl);
    text-transform: none;
}

.article-entry h3 {
    font-size: clamp(1.08rem, 1.6vw, 1.32rem);
    letter-spacing: 0;
    line-height: 1.25;
    margin-top: var(--space-l);
    text-transform: none;
}

.article-entry ul {
    margin: 0 0 var(--space-m);
    padding-left: 1.2rem;
}

.article-entry ol {
    margin: 0 0 var(--space-m);
    padding-left: 1.35rem;
}

.article-entry blockquote {
    margin: var(--space-m) 0;
    padding: var(--space-m) var(--space-l);
    border-left: 4px solid var(--color-accent);
    border-radius: var(--radius-s);
    background: rgba(255,255,255,0.05);
}

.article-entry blockquote p {
    margin: 0;
    color: var(--color-text);
}

.article-dimension-crosses {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--space-m);
    margin: var(--space-l) 0;
}

.article-dimension-card {
    margin: 0;
    padding: var(--space-m);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-s);
    background: rgba(255,255,255,0.04);
}

.article-dimension-card figcaption {
    margin-bottom: 10px;
    color: var(--color-text);
    font-size: 0.92rem;
    font-weight: 700;
}

.article-dimension-crosses .layout {
    --article-cross-face: 38px;
    display: grid;
    grid-template-columns: repeat(3, var(--article-cross-face));
    grid-template-rows: repeat(4, var(--article-cross-face));
    gap: 2px;
    width: max-content;
    max-width: 100%;
    margin: 0 auto;
    padding: 6px;
    border: 1px solid rgba(148, 163, 184, 0.32);
    border-radius: var(--radius-s);
    background: rgba(15, 17, 21, 0.56);
}

.article-dimension-crosses .face.up { grid-column: 2; grid-row: 1; }
.article-dimension-crosses .face.left { grid-column: 1; grid-row: 2; }
.article-dimension-crosses .face.front { grid-column: 2; grid-row: 2; }
.article-dimension-crosses .face.right { grid-column: 3; grid-row: 2; }
.article-dimension-crosses .face.down { grid-column: 2; grid-row: 3; }
.article-dimension-crosses .face.back { grid-column: 2; grid-row: 4; }

.article-dimension-crosses .face {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(4, 1fr);
    background: #f8fafc;
    border: 1px solid #334155;
}

.article-dimension-crosses .cell {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 0;
    min-height: 0;
    border: 1px solid #94a3b8;
    color: #0f172a;
    font-size: 0.5rem;
    font-weight: 700;
    line-height: 1;
}

.article-dimension-crosses .ver .face.up .cell:nth-child(1),
.article-dimension-crosses .ver .face.up .cell:nth-child(5),
.article-dimension-crosses .ver .face.up .cell:nth-child(9),
.article-dimension-crosses .ver .face.up .cell:nth-child(13),
.article-dimension-crosses .ver .face.front .cell:nth-child(1),
.article-dimension-crosses .ver .face.front .cell:nth-child(5),
.article-dimension-crosses .ver .face.front .cell:nth-child(9),
.article-dimension-crosses .ver .face.front .cell:nth-child(13),
.article-dimension-crosses .ver .face.down .cell:nth-child(1),
.article-dimension-crosses .ver .face.down .cell:nth-child(5),
.article-dimension-crosses .ver .face.down .cell:nth-child(9),
.article-dimension-crosses .ver .face.down .cell:nth-child(13),
.article-dimension-crosses .ver .face.back .cell:nth-child(1),
.article-dimension-crosses .ver .face.back .cell:nth-child(5),
.article-dimension-crosses .ver .face.back .cell:nth-child(9),
.article-dimension-crosses .ver .face.back .cell:nth-child(13) {
    background: linear-gradient(135deg, #dff7ff 0%, #a7defc 48%, #7cc8f7 100%);
    border-color: #0284c7;
}

.article-dimension-crosses .hor .face.left .cell:nth-child(1),
.article-dimension-crosses .hor .face.left .cell:nth-child(2),
.article-dimension-crosses .hor .face.left .cell:nth-child(3),
.article-dimension-crosses .hor .face.left .cell:nth-child(4),
.article-dimension-crosses .hor .face.front .cell:nth-child(1),
.article-dimension-crosses .hor .face.front .cell:nth-child(2),
.article-dimension-crosses .hor .face.front .cell:nth-child(3),
.article-dimension-crosses .hor .face.front .cell:nth-child(4),
.article-dimension-crosses .hor .face.right .cell:nth-child(1),
.article-dimension-crosses .hor .face.right .cell:nth-child(2),
.article-dimension-crosses .hor .face.right .cell:nth-child(3),
.article-dimension-crosses .hor .face.right .cell:nth-child(4),
.article-dimension-crosses .hor .face.back .cell:nth-child(13),
.article-dimension-crosses .hor .face.back .cell:nth-child(14),
.article-dimension-crosses .hor .face.back .cell:nth-child(15),
.article-dimension-crosses .hor .face.back .cell:nth-child(16) {
    background: linear-gradient(135deg, #dcfce7 0%, #86efac 48%, #22c55e 100%);
    border-color: #16a34a;
}

.article-dimension-crosses .lat .face.up .cell:nth-child(1),
.article-dimension-crosses .lat .face.up .cell:nth-child(2),
.article-dimension-crosses .lat .face.up .cell:nth-child(3),
.article-dimension-crosses .lat .face.up .cell:nth-child(4),
.article-dimension-crosses .lat .face.left .cell:nth-child(1),
.article-dimension-crosses .lat .face.left .cell:nth-child(5),
.article-dimension-crosses .lat .face.left .cell:nth-child(9),
.article-dimension-crosses .lat .face.left .cell:nth-child(13),
.article-dimension-crosses .lat .face.down .cell:nth-child(13),
.article-dimension-crosses .lat .face.down .cell:nth-child(14),
.article-dimension-crosses .lat .face.down .cell:nth-child(15),
.article-dimension-crosses .lat .face.down .cell:nth-child(16),
.article-dimension-crosses .lat .face.right .cell:nth-child(4),
.article-dimension-crosses .lat .face.right .cell:nth-child(8),
.article-dimension-crosses .lat .face.right .cell:nth-child(12),
.article-dimension-crosses .lat .face.right .cell:nth-child(16) {
    background: linear-gradient(135deg, #fee2e2 0%, #fca5a5 48%, #ef4444 100%);
    border-color: #dc2626;
}

.article-summary {
    color: var(--color-text-soft);
    font-size: 1.08rem;
}

@media (max-width: 900px) {
    .hero-inner,
    .grid-2 {
        grid-template-columns: 1fr;
    }

    .articles-layout {
        grid-template-columns: 1fr;
    }

    .article-index {
        position: static;
    }

    .article-dimension-crosses {
        grid-template-columns: 1fr;
    }
}