/* --- 1. VARIABLES (KIM THEME) --- */
:root {
	--gold: #D4AF37;
	--gold-light: #F4E7BE;
	--silver: #E0E0E0;
	--white: #FFFFFF;
	--dark-metal: #2C3E50;
	--text-main: #333333;
	--bg-body: #FAFAFA;

	--gradient-gold: linear-gradient(135deg, #bf953f, #fcf6ba, #b38728, #fbf5b7, #aa771c);
	--gradient-silver: linear-gradient(135deg, #e0e0e0 0%, #ffffff 50%, #e0e0e0 100%);

	--shadow: 0 10px 40px rgba(0,0,0,0.08);
	--container: 1200px;
}

/* --- 3. HERO SECTION --- */
.hub-hero {
	position: relative; padding: 80px 0; text-align: center; overflow: hidden;
	background: radial-gradient(circle at center, #fff 0%, #f0f0f0 100%);
}
.hero-icon-bg {
	position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
	font-size: 30rem; color: rgba(212, 175, 55, 0.05); z-index: 0;
}
.hero-content { position: relative; z-index: 2; }
.element-symbol {
	width: 100px; height: 100px; border-radius: 50%; background: var(--gradient-gold);
	display: flex; align-items: center; justify-content: center; margin: 0 auto 20px;
	font-size: 3rem; color: white; box-shadow: 0 10px 30px rgba(212, 175, 55, 0.3);
}
.hero-subtitle { 
	font-size: 1.2rem; letter-spacing: 4px; text-transform: uppercase; 
	background: var(--gradient-gold); -webkit-background-clip: text; -webkit-text-fill-color: transparent;
	font-weight: 700; margin-bottom: 30px;
}
.hero-desc { max-width: 700px; margin: 0 auto; color: #666; font-size: 1.1rem; }

/* --- 4. CHEAT SHEET (Tra Cứu Nhanh) --- */
.cheat-sheet { margin-top: -50px; position: relative; z-index: 3; padding-bottom: 80px; }
.cs-grid {
	display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
	background: white; padding: 40px; border-radius: 20px;
	box-shadow: var(--shadow); border: 1px solid rgba(212, 175, 55, 0.2);
}
.cs-item { 
	display: flex; flex-direction: column; align-items: center; text-align: center; 
	padding: 0 20px; border-right: 1px solid #eee;
}
.cs-item:last-child { border-right: none; }
.cs-icon { font-size: 2rem; color: var(--gold); margin-bottom: 15px; }
.cs-label { font-size: 0.9rem; text-transform: uppercase; color: #999; letter-spacing: 1px; margin-bottom: 5px; }
.cs-value { font-size: 1.1rem; font-weight: 700; color: var(--dark-metal); }
.color-dots { display: flex; gap: 5px; justify-content: center; margin-top: 5px; }
.dot { width: 15px; height: 15px; border-radius: 50%; border: 1px solid #ddd; }

/* --- 5. TOPIC CLUSTER NAVIGATION (GRID) --- */
.topic-section { padding: 60px 0; }
.topic-header { text-align: center; margin-bottom: 50px; }
.topic-header h2 { font-size: 2.5rem; color: var(--gray-dark); margin-bottom: 10px; position: relative; display: inline-block; }
.topic-header h2::after {
	content: ''; position: absolute; bottom: -10px; left: 50%; transform: translateX(-50%);
	width: 60px; height: 3px; background: var(--gold);
}

.topic-grid {
	display: grid; grid-template-columns: repeat(2, 1fr); gap: 25px;
}

.topic-card {
	background: white; border-radius: 16px; padding: 25px;
	border: 1px solid rgba(0,0,0,0.05); transition: 0.4s;
	display: flex; flex-direction: column; height: 100%;
	position: relative; overflow: hidden;
}

.topic-card:hover { 
	transform: translateY(-5px); 
	box-shadow: var(--shadow-hover); 
	border-color: var(--gold); 
}

.topic-icon {
	width: 50px; height: 50px; background: var(--gold-light); border-radius: 12px;
	display: flex; align-items: center; justify-content: center;
	color: var(--gold-dark); font-size: 1.5rem; margin-bottom: 20px;
	transition: 0.4s;
}
.topic-card:hover .topic-icon { background: var(--gold); color: white; }

.topic-title { font-size: 1.2rem; font-weight: 700; margin-bottom: 15px; color: var(--gray-dark); }

.link-list { list-style: none; padding-left: 0;}
.link-list li { margin-bottom: 10px; }
.link-list a { 
	display: flex; align-items: center; color: #555; font-size: 1.2rem; 
	transition: 0.2s; padding: 5px 0;
}
.link-list a:hover { color: var(--gold-dark); transform: translateX(5px); }
.link-list a::before {
	content: '•'; color: var(--gold); margin-right: 10px; font-size: 1.2rem;
}


/* --- 6. DETAILED SECTIONS --- */
.detail-sec { border-bottom: 1px solid #eee; }
.sec-header { text-align: center; margin-bottom: 60px; }
.sec-header p { color: #666; max-width: 600px; margin: 0 auto; }

/* Nạp Âm Grid */
.nap-am-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.na-card {
	border: 1px solid #eee; border-radius: 12px; padding: 30px;
	transition: 0.4s; position: relative; overflow: hidden; background: white;
}
.na-card:hover { transform: translateY(-5px); border-color: var(--gold); box-shadow: 0 15px 30px rgba(0,0,0,0.05); }
.na-year { display: inline-block; background: var(--gold-light); color: #8a6d3b; padding: 4px 12px; border-radius: 20px; font-size: 0.8rem; font-weight: 700; margin-bottom: 15px; }
.na-title { font-size: 1.5rem; font-weight: 700; margin-bottom: 10px; color: var(--dark-metal); }
.na-desc { font-size: 0.95rem; color: #666; line-height: 1.6; }
.na-link { margin-top: 15px; display: inline-block; color: var(--gold); font-weight: 600; font-size: 0.9rem; }

/* Năm Sinh Grid (NEW) */
.year-lookup-sec { background: #fcfcfc; }
.year-lookup-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
	gap: 20px;
}
.year-card {
	background: white; border: 1px solid #eee; border-radius: 12px;
	padding: 25px 15px; text-align: center; transition: 0.3s;
	cursor: pointer; position: relative; overflow: hidden;
	display: flex; flex-direction: column; justify-content: center;
}
.year-card:hover {
	border-color: var(--gold); box-shadow: 0 10px 20px rgba(212, 175, 55, 0.15);
	transform: translateY(-5px);
}
.yc-year {
	font-size: 2.2rem; font-weight: 700; color: var(--dark-metal);
	display: block; margin-bottom: 5px; line-height: 1;
}
.yc-canchi {
	font-size: 0.95rem; font-weight: 700; color: var(--gold); text-transform: uppercase;
	margin-bottom: 5px; display: block;
}
.yc-napam {
	font-size: 0.85rem; color: #888; margin-bottom: 10px;
}
.yc-action {
	font-size: 0.8rem; font-weight: 600; color: var(--dark-metal);
	display: flex; align-items: center; justify-content: center; gap: 5px;
	transform: translateY(10px); transition: 0.3s;
	background: #f5f5f5; padding: 5px 10px; border-radius: 20px; width: fit-content; margin: 0 auto;
}
.year-card:hover .yc-action { opacity: 1; transform: translateY(0); }
.year-card:hover .yc-action:hover { background: var(--gold); color: white; }


/* Comparison Table */
.compare-table { width: 100%; border-collapse: collapse; background: white; border-radius: 12px; overflow: hidden; box-shadow: var(--shadow); }
.compare-table th, .compare-table td { padding: 15px 20px; text-align: left; border-bottom: 1px solid #eee; }
.compare-table th { background: var(--dark-metal); color: white; font-weight: 600; }
.compare-table tr:last-child td { border-bottom: none; }
.compare-table tr:hover { background: #fcfcfc; }

/* Lifestyle Grid */
.ls-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; margin-bottom: 80px; }
.ls-grid.reverse { direction: rtl; }
.ls-grid.reverse .ls-content { direction: ltr; }
.ls-img { width: 100%; border-radius: 20px; box-shadow: 0 20px 50px rgba(0,0,0,0.1); height: 400px; object-fit: cover; }
.ls-content h3 { font-size: 2rem; margin-bottom: 20px; color: var(--dark-metal); }
.ls-list li { margin-bottom: 15px; display: flex; gap: 15px; align-items: flex-start; }
.ls-list i { color: var(--gold); margin-top: 5px; }

/* Shop Grid */
.shop-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; }
.item-card { border: 1px solid #eee; border-radius: 12px; overflow: hidden; transition: 0.3s; text-align: center; background: white; }
.item-card:hover { border-color: var(--gold); box-shadow: 0 10px 30px rgba(0,0,0,0.05); }
.item-img { width: 100%; height: 250px; object-fit: cover; background: #f9f9f9; }
.item-info { padding: 20px; }
.item-name { font-weight: 700; color: var(--dark-metal); margin-bottom: 5px; display: block; }
.item-btn { display: inline-block; padding: 8px 20px; border: 1px solid var(--gold); color: var(--gold); border-radius: 20px; font-size: 0.9rem; font-weight: 600; margin-top: 10px; }
.item-card:hover .item-btn { background: var(--gold); color: white; }

/* FAQ Accordion */
.faq-item { background: white; border: 1px solid #eee; border-radius: 8px; margin-bottom: 10px; overflow: hidden; }
.faq-question { padding: 20px; cursor: pointer; font-weight: 600; display: flex; justify-content: space-between; align-items: center; }
.faq-question:hover { background: #f9f9f9; }
.faq-answer { max-height: 0; overflow: hidden; transition: 0.4s ease; padding: 0 20px; color: #666; }
.faq-item.active .faq-answer { max-height: 200px; padding-bottom: 20px; }

/* Footer */
footer { background: var(--dark-metal); color: #ccc; padding: 60px 0 30px; text-align: center; }
.f-links { margin-bottom: 30px; }
.f-links a { color: white; margin: 0 15px; }

/* Responsive */
@media (max-width: 992px) {
	.cs-grid, .nap-am-grid, .ls-grid, .shop-grid { grid-template-columns: 1fr 1fr; }
	.ls-grid { gap: 30px; }
	.ls-grid.reverse { direction: ltr; }
}
@media (max-width: 600px) {
	.cs-grid, .nap-am-grid, .ls-grid, .shop-grid { grid-template-columns: 1fr; }
	.toc-list { gap: 10px; }
}