/* ═══════════════════════════════════════════════════
   NEXUS // Premium PC Hardware – Design System
   ═══════════════════════════════════════════════════ */

:root {
    --bg-main: #060810;
    --bg-surface: #0d1117;
    --bg-elevated: #161b22;
    --bg-hover: #1c2333;
    --accent: #6366f1;
    --accent-bright: #818cf8;
    --accent2: #a855f7;
    --accent-glow: rgba(99,102,241,0.35);
    --green: #10b981;
    --red: #ef4444;
    --text: #e2e8f0;
    --text-muted: #8b95a5;
    --text-dim: #4a5568;
    --border: rgba(99,102,241,0.12);
    --border-bright: rgba(99,102,241,0.35);
    --radius: 10px;
}

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

body {
    font-family: 'Inter', system-ui, sans-serif;
    background: var(--bg-main);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
    /* Subtle grid bg */
    background-image:
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99,102,241,0.12), transparent),
        linear-gradient(rgba(99,102,241,0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(99,102,241,0.04) 1px, transparent 1px);
    background-size: 100% 100%, 50px 50px, 50px 50px;
}

::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-bright); border-radius: 10px; }

h1,h2,h3 { font-family: 'Rajdhani', sans-serif; letter-spacing: 0.5px; }

/* ═══ NAVBAR ═══ */
.navbar {
    display: flex; justify-content: space-between; align-items: center;
    padding: 1rem 2.5rem;
    background: rgba(6,8,16,0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: sticky; top: 0; z-index: 50;
}
.nav-left { display: flex; align-items: center; gap: 1.5rem; }
.logo {
    font-family: 'Rajdhani', sans-serif; font-weight: 700; font-size: 1.8rem;
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    display: flex; align-items: center; gap: 0.5rem;
}
.logo-icon {
    display: inline-block; width: 10px; height: 10px;
    background: var(--accent); box-shadow: 0 0 8px var(--accent);
}
.nav-tag {
    font-family: 'JetBrains Mono', monospace; font-size: 0.7rem;
    color: var(--text-dim); letter-spacing: 2px; text-transform: uppercase;
}
.nav-right { display: flex; align-items: center; gap: 0.6rem; }
.status-dot {
    width: 7px; height: 7px; border-radius: 50%;
    background: var(--green); box-shadow: 0 0 6px var(--green);
    animation: blink 2s infinite;
}
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.4} }
.status-text {
    font-family: 'JetBrains Mono', monospace; font-size: 0.75rem; color: var(--text-dim);
}

/* ═══ LAYOUT ═══ */
.app-layout { display: flex; min-height: calc(100vh - 60px); }
.main-content { flex: 1; padding: 2.5rem; overflow-y: auto; max-height: calc(100vh - 60px); }

/* ═══ HERO ═══ */
.hero {
    display: flex; justify-content: space-between; align-items: center;
    padding: 3rem; margin-bottom: 3rem;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    position: relative; overflow: hidden;
}
.hero::before {
    content: ''; position: absolute; top: -50%; right: -10%; width: 400px; height: 400px;
    background: radial-gradient(circle, rgba(99,102,241,0.15), transparent 70%);
    pointer-events: none;
}
.hero-text h1 { font-size: 2.8rem; color: #fff; line-height: 1.2; }
.gradient-text {
    background: linear-gradient(135deg, var(--accent-bright), var(--accent2));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero-text p { color: var(--text-muted); margin-top: 0.75rem; font-size: 1.05rem; max-width: 440px; }
.hero-stats { display: flex; gap: 1.5rem; z-index: 1; }
.stat-card {
    text-align: center; padding: 1.2rem 1.8rem;
    background: var(--bg-elevated); border: 1px solid var(--border);
    border-radius: var(--radius);
}
.stat-value {
    display: block; font-family: 'JetBrains Mono', monospace; font-size: 1.6rem;
    font-weight: 700; color: var(--accent-bright);
}
.stat-label { font-size: 0.75rem; color: var(--text-dim); text-transform: uppercase; letter-spacing: 1px; }

/* ═══ SECTIONS ═══ */
.section { margin-bottom: 2.5rem; }
.section-header { display: flex; align-items: center; gap: 1rem; margin-bottom: 1.5rem; }
.section-header h2 { font-size: 1.4rem; color: #fff; white-space: nowrap; }
.section-line { flex: 1; height: 1px; background: var(--border); }
.product-count {
    font-family: 'JetBrains Mono', monospace; font-size: 0.8rem; color: var(--text-dim);
    white-space: nowrap;
}

/* ═══ CATEGORIES ═══ */
.categories { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.cat-btn {
    display: flex; align-items: center; gap: 0.5rem;
    background: var(--bg-surface); border: 1px solid var(--border);
    padding: 0.65rem 1.3rem; border-radius: var(--radius);
    color: var(--text-muted); font-family: 'Rajdhani', sans-serif;
    font-size: 0.95rem; font-weight: 600; cursor: pointer;
    transition: all 0.25s ease;
}
.cat-btn:hover { border-color: var(--accent); color: #fff; background: var(--bg-hover); }
.cat-btn.active {
    background: rgba(99,102,241,0.15); border-color: var(--accent);
    color: #fff; box-shadow: 0 0 12px var(--accent-glow);
}
.cat-icon { font-size: 1.1rem; }

/* ═══ PRODUCT CARDS ═══ */
.products-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1.5rem;
}
.product-card {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius); padding: 1.5rem;
    display: flex; flex-direction: column;
    transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
    position: relative;
}
.product-card:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(99,102,241,0.15);
}
.card-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 0.75rem; }
.card-category {
    font-family: 'JetBrains Mono', monospace; font-size: 0.7rem;
    color: var(--accent-bright); text-transform: uppercase; letter-spacing: 1px;
}
.badge-stock {
    font-size: 0.65rem; padding: 0.2rem 0.5rem; border-radius: 4px;
    background: rgba(16,185,129,0.15); color: var(--green);
    font-family: 'JetBrains Mono', monospace; font-weight: 700;
}
.badge-oos {
    font-size: 0.65rem; padding: 0.2rem 0.5rem; border-radius: 4px;
    background: rgba(239,68,68,0.15); color: var(--red);
    font-family: 'JetBrains Mono', monospace; font-weight: 700;
}
.card-name { font-size: 1.2rem; color: #fff; margin-bottom: 0.75rem; font-weight: 700; }

.card-specs { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-bottom: 0.75rem; }
.spec-tag {
    font-family: 'JetBrains Mono', monospace; font-size: 0.68rem;
    padding: 0.25rem 0.55rem; border-radius: 4px;
    background: var(--bg-elevated); border: 1px solid var(--border);
    color: var(--text-muted); white-space: nowrap;
}

.card-desc { font-size: 0.85rem; color: var(--text-dim); line-height: 1.5; flex: 1; margin-bottom: 1.2rem; }

.card-bottom {
    display: flex; justify-content: space-between; align-items: center;
    padding-top: 1rem; border-top: 1px solid var(--border);
}
.card-price {
    font-family: 'JetBrains Mono', monospace; font-size: 1.3rem; font-weight: 700;
    color: var(--accent-bright);
}
.add-btn {
    display: flex; align-items: center; gap: 0.4rem;
    background: transparent; border: 1px solid var(--accent);
    color: var(--accent-bright); padding: 0.5rem 1rem; border-radius: 6px;
    font-family: 'Rajdhani', sans-serif; font-size: 0.95rem; font-weight: 600;
    cursor: pointer; transition: all 0.2s;
}
.add-btn:hover:not(:disabled) {
    background: var(--accent); color: #fff; box-shadow: 0 0 15px var(--accent-glow);
}
.add-btn:disabled { opacity: 0.3; cursor: not-allowed; }

/* ═══ SIDEBAR ═══ */
.sidebar {
    width: 380px; background: var(--bg-surface);
    border-left: 1px solid var(--border);
    display: flex; flex-direction: column;
    max-height: calc(100vh - 60px); position: sticky; top: 60px;
}
.cart-header {
    padding: 1.5rem 1.5rem; border-bottom: 1px solid var(--border);
    display: flex; justify-content: space-between; align-items: center;
}
.cart-header h2 { font-size: 1.2rem; color: #fff; }
.cart-badge {
    font-family: 'JetBrains Mono', monospace; font-size: 0.8rem; font-weight: 700;
    background: var(--accent); color: #fff; padding: 0.15rem 0.6rem; border-radius: 4px;
    min-width: 28px; text-align: center;
}
.cart-items { flex: 1; overflow-y: auto; padding: 1rem 1.5rem; display: flex; flex-direction: column; gap: 0.75rem; }

.empty-cart { text-align: center; padding: 3rem 1rem; color: var(--text-dim); }
.empty-icon { font-size: 2.5rem; margin-bottom: 1rem; opacity: 0.3; }
.empty-cart p { font-weight: 600; margin-bottom: 0.25rem; }
.empty-cart span { font-size: 0.8rem; }

.cart-item {
    display: grid; grid-template-columns: 1fr auto auto; align-items: center; gap: 1rem;
    padding: 1rem; background: var(--bg-elevated); border: 1px solid var(--border);
    border-radius: 8px; border-left: 3px solid var(--accent);
}
.ci-info h4 { font-family: 'Rajdhani', sans-serif; font-size: 0.95rem; color: #fff; margin-bottom: 0.15rem; }
.ci-unit { font-family: 'JetBrains Mono', monospace; font-size: 0.7rem; color: var(--text-dim); }
.ci-controls { display: flex; align-items: center; gap: 0.4rem; }
.qty-btn {
    width: 26px; height: 26px; border-radius: 4px;
    background: var(--bg-main); border: 1px solid var(--border);
    color: var(--text); cursor: pointer; font-size: 1rem;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.15s;
}
.qty-btn:hover { border-color: var(--accent); color: var(--accent-bright); }
.qty-val { font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; min-width: 18px; text-align: center; }
.ci-subtotal { font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; color: var(--accent-bright); font-weight: 700; }

.cart-footer { padding: 1.5rem; border-top: 1px solid var(--border); background: var(--bg-elevated); }
.cart-row { display: flex; justify-content: space-between; margin-bottom: 0.6rem; font-size: 0.9rem; color: var(--text-muted); }
.cart-row span:last-child { font-family: 'JetBrains Mono', monospace; }
.cart-total { font-size: 1.15rem; font-weight: 700; color: #fff; margin-top: 0.75rem; padding-top: 0.75rem; border-top: 1px solid var(--border); }
.cart-total span:last-child { color: var(--accent-bright); text-shadow: 0 0 8px var(--accent-glow); }

.checkout-btn {
    width: 100%; margin-top: 1.2rem; padding: 1rem;
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    border: none; border-radius: 8px; color: #fff;
    font-family: 'Rajdhani', sans-serif; font-size: 1.1rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 1px;
    cursor: pointer; transition: all 0.3s;
    display: flex; justify-content: center; align-items: center; gap: 0.5rem;
}
.checkout-btn:hover:not(:disabled) { box-shadow: 0 4px 20px var(--accent-glow); transform: translateY(-1px); }
.checkout-btn:disabled { opacity: 0.3; cursor: not-allowed; transform: none; box-shadow: none; }
.btn-arrow { transition: transform 0.2s; }
.checkout-btn:hover:not(:disabled) .btn-arrow { transform: translateX(4px); }

/* ═══ MOBILE CART TOGGLE ═══ */
.cart-toggle {
    display: none; position: fixed; bottom: 1.5rem; right: 1.5rem;
    width: 56px; height: 56px; border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    border: none; color: #fff; font-size: 1.3rem; cursor: pointer;
    box-shadow: 0 4px 20px var(--accent-glow); z-index: 60;
}
.toggle-badge {
    position: absolute; top: -4px; right: -4px;
    background: var(--red); color: #fff; font-size: 0.7rem; font-weight: 700;
    width: 20px; height: 20px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
}

/* ═══ TOAST ═══ */
.toast {
    position: fixed; bottom: 2rem; left: 50%; transform: translateX(-50%) translateY(80px);
    background: var(--bg-elevated); border: 1px solid var(--green);
    padding: 0.85rem 1.5rem; border-radius: 8px;
    display: flex; align-items: center; gap: 0.6rem;
    font-size: 0.9rem; color: #fff; z-index: 100;
    box-shadow: 0 4px 20px rgba(16,185,129,0.2);
    transition: transform 0.35s cubic-bezier(0.4,0,0.2,1), opacity 0.35s;
    opacity: 0;
}
.toast.show { transform: translateX(-50%) translateY(0); opacity: 1; }
.toast-icon { color: var(--green); font-weight: bold; }

.loader {
    font-family: 'JetBrains Mono', monospace; color: var(--accent); font-size: 0.85rem;
    animation: pulse 1.5s infinite;
}
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.4} }
.error-msg { color: var(--red); font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; }

/* ═══ RESPONSIVE ═══ */
@media (max-width: 1024px) {
    .sidebar { position: fixed; top: 0; right: 0; bottom: 0; width: 360px; z-index: 55; transform: translateX(100%); transition: transform 0.3s ease; max-height: 100vh; }
    .sidebar.open { transform: translateX(0); box-shadow: -10px 0 30px rgba(0,0,0,0.5); }
    .cart-toggle { display: flex; align-items: center; justify-content: center; }
    .hero { flex-direction: column; gap: 2rem; text-align: center; }
    .hero-text p { max-width: 100%; }
}
@media (max-width: 640px) {
    .main-content { padding: 1.5rem; }
    .hero { padding: 2rem 1.5rem; }
    .hero-text h1 { font-size: 2rem; }
    .hero-stats { gap: 0.75rem; }
    .stat-card { padding: 0.8rem 1rem; }
    .products-grid { grid-template-columns: 1fr; }
    .navbar { padding: 1rem 1.25rem; }
    .nav-tag { display: none; }
}