/* ============================================
   tientuan.io — Dark/Cyan Premium Theme
   ============================================ */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --bg: #0a0a0a; --bg2: #111318; --bg-card: #141820; --bg-card-hover: #1a1f2e;
    --border: #1e2536; --border-accent: #00e5cc;
    --text: #ededed; --text2: #9ca3af; --text3: #6b7280;
    --accent: #00e5cc; --accent-hover: #00ffdd; --accent-glow: rgba(0,229,204,.15);
    --violet: #8b5cf6; --violet-glow: rgba(139,92,246,.15);
    --red: #ef4444; --green: #10b981; --yellow: #fbbf24;
    --gradient: linear-gradient(135deg, #00e5cc, #8b5cf6);
    --radius: 12px; --radius-lg: 16px; --max-w: 1200px;
}

html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, sans-serif; background: var(--bg); color: var(--text); line-height: 1.6; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }

/* NAVBAR */
.navbar { position: fixed; top: 0; left: 0; right: 0; z-index: 100; background: rgba(10,10,10,.85); backdrop-filter: blur(20px); border-bottom: 1px solid var(--border); }
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.navbar-logo { font-size: 14px; font-weight: 800; letter-spacing: 3px; text-transform: uppercase; color: var(--accent); }
.navbar-links { display: flex; gap: 32px; align-items: center; }
.navbar-links a { font-size: 14px; color: var(--text2); transition: color .2s; }
.navbar-links a:hover { color: var(--text); }
.navbar-cta { padding: 8px 20px !important; border-radius: 8px; background: var(--accent); color: #0a0a0a !important; font-weight: 600 !important; font-size: 13px; transition: all .2s; }
.navbar-cta:hover { background: var(--accent-hover); transform: translateY(-1px); }
.mobile-menu { display: none; cursor: pointer; color: var(--text); font-size: 24px; }

/* HERO MINI */
.hero-mini { padding: 100px 0 40px; }
.section { padding: 60px 0; }
.section-label { font-size: 12px; font-weight: 700; letter-spacing: 3px; text-transform: uppercase; color: var(--accent); margin-bottom: 12px; }
.section-title { font-size: clamp(28px,3.5vw,40px); font-weight: 800; margin-bottom: 12px; letter-spacing: -.5px; }
.section-desc { font-size: 16px; color: var(--text2); max-width: 600px; margin-bottom: 32px; }

/* BUTTONS */
.btn-primary { display: inline-flex; align-items: center; gap: 8px; padding: 14px 28px; border-radius: 10px; background: var(--accent); color: #0a0a0a; font-weight: 700; font-size: 15px; transition: all .3s; border: none; cursor: pointer; font-family: inherit; }
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-2px); box-shadow: 0 8px 30px var(--accent-glow); }
.btn-secondary { display: inline-flex; align-items: center; gap: 8px; padding: 14px 28px; border-radius: 10px; background: transparent; color: var(--text); font-weight: 600; font-size: 15px; border: 1px solid var(--border); transition: all .3s; cursor: pointer; font-family: inherit; }
.btn-secondary:hover { border-color: var(--text2); background: var(--bg-card); }

/* CATEGORY FILTER */
.cat-filter { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 32px; }
.cat-btn { padding: 8px 18px; border-radius: 8px; font-size: 13px; font-weight: 600; color: var(--text2); background: var(--bg-card); border: 1px solid var(--border); transition: all .2s; }
.cat-btn:hover, .cat-btn.active { color: var(--accent); border-color: var(--accent); background: var(--accent-glow); }

/* PRODUCTS GRID */
.products-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 20px; }
.product-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 28px; transition: all .3s; position: relative; display: flex; flex-direction: column; }
.product-card:hover { border-color: var(--accent); transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,229,204,.06); }
.product-badge { position: absolute; top: 16px; right: 16px; padding: 4px 12px; border-radius: 6px; font-size: 11px; font-weight: 700; text-transform: uppercase; }
.badge-cyan { background: var(--accent-glow); color: var(--accent); }
.badge-red { background: rgba(239,68,68,.15); color: var(--red); }
.badge-violet { background: var(--violet-glow); color: var(--violet); }
.badge-green { background: rgba(16,185,129,.15); color: var(--green); }
.badge-yellow { background: rgba(251,191,36,.15); color: var(--yellow); }
.product-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 8px; padding-right: 60px; }
.product-desc { font-size: 14px; color: var(--text2); margin-bottom: 16px; line-height: 1.6; }
.product-features { list-style: none; margin-bottom: 20px; }
.product-features li { font-size: 13px; color: var(--text2); padding: 4px 0; padding-left: 20px; position: relative; }
.product-features li::before { content: '✓'; position: absolute; left: 0; color: var(--accent); font-weight: 700; }
.product-footer { margin-top: auto; }
.product-price { margin-bottom: 4px; }
.price-label { font-size: 12px; color: var(--text3); display: block; }
.price-old { font-size: 14px; color: var(--text3); text-decoration: line-through; margin-right: 8px; }
.price-current { font-size: 22px; font-weight: 800; color: var(--accent); }
.product-delivery { font-size: 12px; color: var(--text3); margin-top: 4px; }

/* REVIEWS GRID */
.reviews-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 20px; }
.review-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; transition: all .3s; display: block; }
.review-card:hover { border-color: var(--accent); transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,229,204,.06); }
.review-card-img { width: 100%; height: 180px; background: var(--bg2); display: flex; align-items: center; justify-content: center; font-size: 48px; }
.review-card-body { padding: 24px; }
.review-card-tags { display: flex; gap: 8px; margin-bottom: 12px; flex-wrap: wrap; }
.tag { padding: 4px 10px; border-radius: 6px; font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: .5px; }
.tag-hot { background: rgba(239,68,68,.15); color: var(--red); }
.tag-new { background: var(--accent-glow); color: var(--accent); }
.tag-popular { background: var(--violet-glow); color: var(--violet); }
.tag-compare { background: rgba(251,191,36,.15); color: var(--yellow); }
.review-card h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; line-height: 1.3; }
.review-card p { font-size: 14px; color: var(--text2); margin-bottom: 16px; line-height: 1.6; }
.review-card-footer { display: flex; justify-content: space-between; align-items: center; }
.review-date { font-size: 12px; color: var(--text3); }
.review-rating { display: flex; gap: 2px; }
.star { color: var(--yellow); font-size: 14px; }
.star.empty { color: var(--text3); }

/* ARTICLE */
.article-content { max-width: 800px; }
.article-excerpt { font-size: 18px; color: var(--text2); line-height: 1.7; margin-bottom: 32px; padding-bottom: 24px; border-bottom: 1px solid var(--border); font-style: italic; }
.article-body { font-size: 16px; line-height: 1.8; color: var(--text); }
.article-body h2 { font-size: 24px; font-weight: 700; margin: 32px 0 12px; color: var(--text); }
.article-body h3 { font-size: 20px; font-weight: 600; margin: 24px 0 8px; }
.article-body p { margin-bottom: 16px; }
.article-body ul, .article-body ol { margin: 16px 0; padding-left: 24px; }
.article-body li { margin-bottom: 8px; }
.article-body code { background: var(--bg2); padding: 2px 8px; border-radius: 4px; font-size: 14px; }
.article-body blockquote { border-left: 3px solid var(--accent); padding: 12px 20px; margin: 20px 0; background: var(--bg-card); border-radius: 0 8px 8px 0; }
.article-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 32px; padding-top: 24px; border-top: 1px solid var(--border); }
.article-cta { margin-top: 40px; }

/* CHECKOUT */
.checkout-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 24px; }
.checkout-success { max-width: 500px; margin: 0 auto; text-align: center; }
.qr-section h2 { margin-bottom: 8px; }
.qr-code { margin: 24px 0; }
.qr-code img { box-shadow: 0 4px 20px rgba(0,0,0,.3); }
.bank-info { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; text-align: left; margin: 20px 0; }
.bank-info p { margin-bottom: 8px; font-size: 14px; }
.checkout-note { background: var(--accent-glow); border: 1px solid rgba(0,229,204,.2); border-radius: var(--radius); padding: 16px; margin-top: 16px; }
.checkout-note p { font-size: 14px; margin-bottom: 4px; }
.card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.card h2 { font-size: 18px; font-weight: 700; margin-bottom: 16px; }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 13px; color: var(--text2); margin-bottom: 6px; }
.form-group input, .form-group textarea { width: 100%; padding: 12px 16px; border-radius: 10px; border: 1px solid var(--border); background: var(--bg); color: var(--text); font-size: 15px; font-family: inherit; outline: none; transition: border .2s; }
.form-group input:focus, .form-group textarea:focus { border-color: var(--accent); }
.form-group textarea { min-height: 80px; resize: vertical; }
.cart-item { display: flex; justify-content: space-between; padding: 12px 0; border-bottom: 1px solid var(--border); font-size: 14px; }

/* CART FLOAT */
.cart-float { position: fixed; bottom: 24px; right: 24px; width: 56px; height: 56px; border-radius: 50%; background: var(--accent); display: flex; align-items: center; justify-content: center; font-size: 24px; cursor: pointer; box-shadow: 0 4px 20px var(--accent-glow); transition: all .3s; z-index: 99; }
.cart-float:hover { transform: scale(1.1); }
.cart-float span { position: absolute; top: -4px; right: -4px; background: var(--red); color: #fff; width: 20px; height: 20px; border-radius: 50%; font-size: 11px; font-weight: 700; display: flex; align-items: center; justify-content: center; }

/* TOAST */
.toast-notify { position: fixed; bottom: 90px; right: 24px; background: var(--bg-card); border: 1px solid var(--accent); color: var(--accent); padding: 12px 20px; border-radius: 10px; font-size: 14px; font-weight: 600; opacity: 0; transform: translateY(10px); transition: all .3s; z-index: 999; }
.toast-notify.show { opacity: 1; transform: translateY(0); }

/* FOOTER */
.footer { padding: 60px 0 30px; border-top: 1px solid var(--border); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand p { font-size: 14px; color: var(--text2); max-width: 280px; line-height: 1.6; margin-top: 12px; }
.footer-col h4 { font-size: 13px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px; }
.footer-col a { display: block; font-size: 14px; color: var(--text2); margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: var(--accent); }
.footer-bottom { padding-top: 24px; border-top: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }
.footer-bottom p { font-size: 13px; color: var(--text3); }

/* REVEAL */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity .6s, transform .6s; }
.reveal.revealed { opacity: 1; transform: translateY(0); }

/* RESPONSIVE */
@media (max-width: 768px) {
    .navbar-links { display: none; }
    .mobile-menu { display: block; }
    .navbar-links.active { display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: var(--bg); border-bottom: 1px solid var(--border); padding: 20px 24px; gap: 16px; }
    .products-grid { grid-template-columns: 1fr; }
    .reviews-grid { grid-template-columns: 1fr; }
    .checkout-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .footer-bottom { flex-direction: column; gap: 12px; text-align: center; }
}