/* ============================================================
   TRAKANALYTICA DATA LAB — DATA CHALLENGES PAGE
   Scope: data-challenges.php (+ challenge-detail.php) only
   Depends on: style.css, header.css, footer.css
   Tone: bold, competitive, high-energy — deep navy/charcoal hero,
   brand-purple accents, gold/amber for prizes and winners.
   Deliberately distinct from the light academic tone of
   research-opportunities.css.
   ============================================================ */

:root {
    --dc-navy: #0a0e1e;
    --dc-navy-2: #12172c;
    --dc-charcoal: #14142b;
    --dc-gold: #f0b429;
    --dc-gold-soft: rgba(240,180,41,0.14);
    --dc-gold-border: rgba(240,180,41,0.4);
}

/* ══════════════════════════════════════════
   HERO
══════════════════════════════════════════ */
.dc-hero {
    position: relative;
    overflow: hidden;
    padding: 110px 0 90px;
    display: flex;
    align-items: center;
    background: linear-gradient(150deg, #0a0e1e 0%, #12172c 55%, #1c1440 100%);
}
.dc-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image: url('https://images.unsplash.com/photo-1454165804606-c3d57bc86b40?auto=format&fit=crop&w=1920&q=80');
    background-size: cover;
    background-position: center center;
    background-repeat: no-repeat;
    z-index: 0;
}
.dc-hero-bg {
    position: absolute;
    inset: 0;
    z-index: 1;
    background: linear-gradient(
        110deg,
        rgba(10,14,30,0.88) 0%,
        rgba(18,23,44,0.82) 50%,
        rgba(28,20,64,0.85) 100%
    );
}
.dc-hero-blob {
    position: absolute;
    z-index: 1;
    border-radius: 50%;
    filter: blur(70px);
    pointer-events: none;
    opacity: 0.35;
    animation: dcBlobDrift 14s ease-in-out infinite;
}
.dc-hero-blob-1 {
    width: 380px; height: 380px;
    top: -120px; right: 6%;
    background: radial-gradient(circle, rgba(124,58,237,0.3), transparent 70%);
}
.dc-hero-blob-2 {
    width: 300px; height: 300px;
    bottom: -100px; left: 4%;
    background: radial-gradient(circle, rgba(240,180,41,0.22), transparent 70%);
    animation-delay: 3s;
}
@keyframes dcBlobDrift {
    0%, 100% { transform: translate(0, 0) scale(1); }
    50%      { transform: translate(24px, -18px) scale(1.08); }
}
.dc-hero-grid {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: minmax(0, 900px) 1fr;
    align-items: center;
    gap: 48px;
}
.dc-hero-inner {
    max-width: 900px;
    background: rgba(255,255,255,0.94);
    border-left: 4px solid var(--dc-gold);
    border-radius: 18px;
    padding: 40px 48px 36px;
    box-shadow: 0 20px 50px -22px rgba(240,180,41,0.28);
}
.dc-hero-tag {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    font-size: 0.73rem;
    font-weight: 700;
    letter-spacing: 0.11em;
    text-transform: uppercase;
    color: var(--dc-gold);
    background: var(--dc-gold-soft);
    border: 1px solid var(--dc-gold-border);
    border-radius: 100px;
    padding: 5px 14px;
    margin-bottom: 22px;
}
.dc-hero-tag .fa { font-size: 0.7rem; }
.dc-hero h1 {
    font-size: clamp(2.1rem, 3.6vw, 3.2rem);
    font-weight: 800;
    color: var(--text-primary);
    line-height: 1.12;
    margin-bottom: 10px;
}
.dc-hero p {
    color: var(--text-secondary);
    font-size: 1.02rem;
    line-height: 1.75;
    margin-bottom: 14px;
    max-width: 820px;
}
.dc-hero-ctas {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    margin-top: 22px;
}

/* Hero visual (right column) */
.dc-hero-visual {
    position: relative;
    z-index: 2;
    width: 100%;
}
.dc-hv-card {
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: 20px;
    padding: 24px;
    box-shadow: 0 20px 56px -24px rgba(240,180,41,0.24);
}
.dc-hv-card-label {
    display: block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--dc-gold);
    margin-bottom: 16px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--border-subtle);
}
.dc-hv-step {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-subtle);
}
.dc-hv-step:last-child { border-bottom: none; }
.dc-hv-step-icon {
    flex-shrink: 0;
    width: 38px; height: 38px;
    border-radius: 10px;
    background: var(--dc-gold-soft);
    color: var(--dc-gold);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.95rem;
}
.dc-hv-step-label {
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* ══════════════════════════════════════════
   FEATURED CHALLENGE CARD
══════════════════════════════════════════ */
.dc-featured-wrap { margin-top: -52px; position: relative; z-index: 2; }
.dc-featured-card {
    background: linear-gradient(160deg, var(--dc-charcoal), var(--dc-navy-2));
    border: 1px solid rgba(124,58,237,0.35);
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: 0 24px 60px rgba(0,0,0,0.35);
    color: #fff;
}
.dc-featured-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: #c4b5fd;
    margin-bottom: 12px;
}
.dc-featured-eyebrow .dot {
    width: 7px; height: 7px; border-radius: 50%;
    background: #34d399; box-shadow: 0 0 0 4px rgba(52,211,153,0.2);
}
.dc-featured-card h2 { color: #fff; font-size: clamp(1.5rem, 3vw, 2.1rem); margin-bottom: 12px; }
.dc-featured-card > p.dc-lede { color: rgba(255,255,255,0.72); font-size: 1rem; line-height: 1.7; max-width: 640px; margin-bottom: 30px; }

/* Countdown */
.dc-countdown {
    display: flex;
    gap: 12px;
    margin-bottom: 32px;
}
.dc-countdown-box {
    background: rgba(124,58,237,0.14);
    border: 1px solid rgba(124,58,237,0.35);
    border-radius: var(--radius-sm);
    padding: 14px 18px;
    text-align: center;
    min-width: 76px;
}
.dc-countdown-box .num {
    display: block;
    font-size: 1.6rem;
    font-weight: 800;
    color: #fff;
    font-variant-numeric: tabular-nums;
}
.dc-countdown-box .lbl {
    display: block;
    font-size: 0.66rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #c4b5fd;
    margin-top: 4px;
}

.dc-detail-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 20px;
    padding: 24px 0;
    border-top: 1px solid rgba(255,255,255,0.1);
    border-bottom: 1px solid rgba(255,255,255,0.1);
    margin-bottom: 28px;
}
.dc-detail-item .lbl {
    display: block;
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    color: rgba(255,255,255,0.5);
    margin-bottom: 6px;
}
.dc-detail-item .val { font-size: 1rem; font-weight: 700; color: #fff; }
.dc-detail-item .val.gold { color: var(--dc-gold); }

/* ══════════════════════════════════════════
   WHY JOIN
══════════════════════════════════════════ */
.dc-benefits-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
    margin-top: 8px;
}
.dc-benefit-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 22px 18px;
    text-align: center;
    transition: var(--transition);
}
.dc-benefit-card:hover { transform: translateY(-3px); border-color: var(--border-medium); box-shadow: 0 10px 26px rgba(109,40,217,0.08); }
.dc-benefit-icon {
    width: 42px; height: 42px; border-radius: 11px;
    background: var(--accent-glow-soft); color: var(--accent-primary);
    display: flex; align-items: center; justify-content: center;
    font-size: 1rem; margin: 0 auto 12px;
}
.dc-benefit-card p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5; }

/* ══════════════════════════════════════════
   HOW IT WORKS
══════════════════════════════════════════ */
.dc-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 22px;
    counter-reset: dc-step;
}
.dc-step {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 30px 22px 24px;
}
.dc-step-num {
    width: 38px; height: 38px; border-radius: 10px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: #fff; font-weight: 800; font-size: 1rem;
    display: flex; align-items: center; justify-content: center;
    margin-bottom: 16px;
}
.dc-step h3 { font-size: 1rem; margin-bottom: 8px; }
.dc-step p { font-size: 0.87rem; color: var(--text-secondary); line-height: 1.6; }

/* ══════════════════════════════════════════
   EVALUATION CRITERIA
══════════════════════════════════════════ */
.dc-criteria-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
    max-width: 820px;
    margin: 0 auto;
}
.dc-criteria-item {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    padding: 16px 18px;
}
.dc-criteria-item i { color: var(--accent-primary); font-size: 1rem; flex-shrink: 0; }
.dc-criteria-item span { font-size: 0.9rem; color: var(--text-secondary); font-weight: 600; }

/* ══════════════════════════════════════════
   RECOGNITION
══════════════════════════════════════════ */
.dc-recognition {
    background: linear-gradient(160deg, var(--dc-charcoal), var(--dc-navy-2));
    border-radius: var(--radius-xl);
    padding: 46px 40px;
    color: #fff;
}
.dc-recognition .section-tag { color: var(--dc-gold); background: var(--dc-gold-soft); border-color: var(--dc-gold-border); }
.dc-recognition h2 { color: #fff; }
.dc-recognition-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
    margin-top: 28px;
}
.dc-recognition-item {
    display: flex;
    align-items: center;
    gap: 12px;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-sm);
    padding: 15px 18px;
}
.dc-recognition-item i { color: var(--dc-gold); font-size: 1.05rem; flex-shrink: 0; }
.dc-recognition-item span { font-size: 0.88rem; color: rgba(255,255,255,0.85); }

/* ══════════════════════════════════════════
   PAST WINNERS
══════════════════════════════════════════ */
.dc-winners-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}
.dc-winner-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 26px;
    transition: var(--transition);
}
.dc-winner-card:hover { transform: translateY(-3px); box-shadow: 0 10px 28px rgba(109,40,217,0.08); }
.dc-winner-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: #92400e;
    background: var(--dc-gold-soft);
    border: 1px solid var(--dc-gold-border);
    border-radius: 100px;
    padding: 4px 11px;
    margin-bottom: 14px;
}
.dc-winner-badge i { color: var(--dc-gold); }
.dc-winner-card h4 { font-size: 1rem; margin-bottom: 4px; }
.dc-winner-challenge { font-size: 0.8rem; color: var(--accent-secondary); font-weight: 600; margin-bottom: 12px; }
.dc-winner-card p.dc-desc { font-size: 0.87rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: 16px; }
.dc-winner-card .btn { width: 100%; justify-content: center; }

.dc-placeholder-note {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.82rem;
    color: #92400e;
    background: rgba(217,119,6,0.08);
    border: 1px dashed rgba(217,119,6,0.35);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
}

/* ══════════════════════════════════════════
   RULES / FOOTNOTE
══════════════════════════════════════════ */
.dc-rules-box {
    max-width: 840px;
    margin: 0 auto;
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 26px 30px;
    text-align: center;
}
.dc-rules-box p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.7; }
.dc-rules-box p + p { margin-top: 10px; }

/* ══════════════════════════════════════════
   REGISTRATION MODAL
══════════════════════════════════════════ */
.dc-modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(10,8,20,0.65);
    backdrop-filter: blur(3px);
    z-index: 1000;
    padding: 24px;
    overflow-y: auto;
}
.dc-modal-overlay.open { display: flex; align-items: flex-start; justify-content: center; }
.dc-modal {
    background: #fff;
    border-radius: var(--radius-lg);
    max-width: 560px;
    width: 100%;
    margin: 40px 0;
    overflow: hidden;
    animation: fadeInUp 0.25s ease;
}
.dc-modal-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    padding: 26px 28px;
    border-bottom: 1px solid var(--border-subtle);
}
.dc-modal-header h2 { font-size: 1.2rem; }
.dc-modal-header p { font-size: 0.85rem; color: var(--text-muted); margin-top: 4px; }
.dc-modal-close {
    background: var(--bg-surface); border: none; width: 32px; height: 32px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center; cursor: pointer;
    color: var(--text-secondary); flex-shrink: 0;
}
.dc-modal-close:hover { background: var(--accent-glow-soft); color: var(--accent-primary); }
.dc-modal-body { padding: 26px 28px 30px; }
.dc-form-group { margin-bottom: 16px; }
.dc-form-group label { display: block; font-size: 0.85rem; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.dc-form-group .form-input { width: 100%; }
.dc-form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.dc-modal-note {
    font-size: 0.78rem;
    color: var(--text-muted);
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    margin-bottom: 18px;
}
.dc-modal-success { display: none; text-align: center; padding: 20px 10px 6px; }
.dc-modal-success.show { display: block; }
.dc-modal-success .icon {
    width: 60px; height: 60px; border-radius: 50%;
    background: rgba(5,150,105,0.1); color: #059669;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.5rem; margin: 0 auto 18px;
}
.dc-modal-body.hide-form { display: none; }

/* ══════════════════════════════════════════
   RESPONSIVE
══════════════════════════════════════════ */
@media (max-width: 1200px) {
    .dc-hero-grid { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 1000px) {
    .dc-benefits-grid { grid-template-columns: repeat(2, 1fr); }
    .dc-steps { grid-template-columns: repeat(2, 1fr); }
    .dc-criteria-list { grid-template-columns: 1fr; }
    .dc-recognition-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .dc-hero { padding: 80px 0 60px; }
    .dc-hero-inner { padding: 32px 28px 28px; }
    .dc-hero h1 { font-size: clamp(1.8rem, 3vw, 2.8rem); }
}

@media (max-width: 640px) {
    .dc-hero { padding: 60px 0 48px; }
    .dc-hero-inner { padding: 24px 20px; border-radius: 14px; }
    .dc-hero h1 { font-size: clamp(1.5rem, 2.5vw, 2.2rem); }
    .dc-hero p { font-size: 0.95rem; }
    .dc-hv-card { padding: 18px; }
    
    .dc-benefits-grid { grid-template-columns: 1fr; }
    .dc-steps { grid-template-columns: 1fr; }
    .dc-countdown { flex-wrap: wrap; }
    .dc-featured-card { padding: 26px 20px; }
    .dc-form-row { grid-template-columns: 1fr; }
    .dc-modal { margin: 0; border-radius: var(--radius-md); }
    .dc-modal-overlay { padding: 0; }
    .dc-modal-overlay.open { align-items: flex-end; }
}