/* ========== INTERCAMBIO USA — Design System ========== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&display=swap');

/* ── Tokens ── */
:root {
  --navy-900:#0a1628;--navy-800:#111d35;--navy-700:#1a2744;
  --blue-600:#2563eb;--blue-500:#3b82f6;--blue-400:#60a5fa;
  --amber-500:#f59e0b;--amber-400:#fbbf24;
  --green-500:#10b981;--red-500:#ef4444;
  --gray-50:#f8fafc;--gray-100:#f1f5f9;--gray-200:#e2e8f0;--gray-300:#cbd5e1;
  --gray-400:#94a3b8;--gray-500:#64748b;--gray-600:#475569;--gray-700:#334155;--gray-800:#1e293b;
  --white:#fff;--black:#000;
  --font-sans:'Inter',system-ui,-apple-system,sans-serif;
  --radius-sm:8px;--radius-md:12px;--radius-lg:16px;--radius-xl:24px;
  --shadow-sm:0 1px 3px rgba(0,0,0,.08);
  --shadow-md:0 4px 12px rgba(0,0,0,.12);
  --shadow-lg:0 8px 30px rgba(0,0,0,.18);
  --shadow-xl:0 16px 50px rgba(0,0,0,.25);
  --transition:all .3s cubic-bezier(.4,0,.2,1);
  --max-w:1200px;
}

/* ── Reset ── */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px;-webkit-text-size-adjust:100%}
body{font-family:var(--font-sans);color:var(--gray-800);background:var(--gray-50);line-height:1.7;overflow-x:hidden}
img{max-width:100%;height:auto;display:block}
a{color:var(--blue-600);text-decoration:none;transition:var(--transition)}
a:hover{color:var(--blue-500)}
ul,ol{list-style:none}
table{border-collapse:collapse;width:100%}
button{cursor:pointer;font-family:inherit;border:none;background:none}

/* ── Container ── */
.container{width:100%;max-width:var(--max-w);margin:0 auto;padding:0 20px}

/* ── HEADER ── */
.site-header{background:var(--white);border-bottom:1px solid var(--gray-200);position:sticky;top:0;z-index:1000;backdrop-filter:blur(12px);background:rgba(255,255,255,.92)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px;max-width:var(--max-w);margin:0 auto;padding:0 20px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:1.25rem;color:var(--navy-900)}
.logo svg{width:36px;height:36px}
.logo span{background:linear-gradient(135deg,var(--blue-600),var(--blue-400));-webkit-background-clip:text;-webkit-text-fill-color:transparent}

/* Desktop Nav */
.main-nav{display:none}
.main-nav ul{display:flex;gap:4px}
.main-nav>ul>li{position:relative}
.main-nav a,.main-nav button.nav-toggle{display:flex;align-items:center;gap:4px;padding:8px 14px;font-size:.9rem;font-weight:500;color:var(--gray-700);border-radius:var(--radius-sm);transition:var(--transition)}
.main-nav a:hover,.main-nav button.nav-toggle:hover{background:var(--gray-100);color:var(--blue-600)}
.nav-toggle::after{content:'';border:solid var(--gray-400);border-width:0 2px 2px 0;padding:3px;transform:rotate(45deg);transition:var(--transition)}
.nav-toggle:hover::after{border-color:var(--blue-600)}

/* Dropdown */
.dropdown{position:absolute;top:100%;left:0;min-width:260px;background:var(--white);border-radius:var(--radius-md);box-shadow:var(--shadow-lg);padding:8px;opacity:0;visibility:hidden;transform:translateY(8px);transition:var(--transition);border:1px solid var(--gray-200)}
.main-nav li:hover>.dropdown{opacity:1;visibility:visible;transform:translateY(0)}
.dropdown a{padding:10px 14px;border-radius:var(--radius-sm);font-size:.875rem;display:block;color:var(--gray-700)}
.dropdown a:hover{background:var(--blue-600);color:var(--white)}

/* Hamburger */
.menu-toggle{display:flex;flex-direction:column;gap:5px;padding:8px;cursor:pointer;z-index:1001}
.menu-toggle span{display:block;width:24px;height:2px;background:var(--gray-800);transition:var(--transition)}
.menu-toggle.active span:nth-child(1){transform:rotate(45deg) translate(5px,5px)}
.menu-toggle.active span:nth-child(2){opacity:0}
.menu-toggle.active span:nth-child(3){transform:rotate(-45deg) translate(5px,-5px)}

/* Mobile Nav */
.mobile-nav{position:fixed;top:64px;left:0;right:0;bottom:0;background:var(--white);z-index:999;overflow-y:auto;transform:translateX(100%);transition:transform .35s ease;padding:20px}
.mobile-nav.open{transform:translateX(0)}
.mobile-nav>ul>li{border-bottom:1px solid var(--gray-200)}
.mobile-nav a,.mobile-nav button.mob-toggle{display:flex;align-items:center;justify-content:space-between;width:100%;padding:14px 8px;font-size:1rem;font-weight:500;color:var(--gray-800)}
.mob-toggle::after{content:'▾';font-size:.8rem;transition:var(--transition)}
.mob-toggle.open::after{transform:rotate(180deg)}
.mobile-sub{display:none;padding-left:16px}
.mobile-sub.open{display:block}
.mobile-sub a{font-size:.9rem;color:var(--gray-600);padding:10px 8px}

/* ── HERO ── */
.hero{background:linear-gradient(135deg,var(--navy-900) 0%,var(--navy-700) 50%,#1e3a5f 100%);color:var(--white);padding:60px 0 50px;position:relative;overflow:hidden}
.hero::before{content:'';position:absolute;top:-40%;right:-20%;width:600px;height:600px;background:radial-gradient(circle,rgba(37,99,235,.15) 0%,transparent 70%);border-radius:50%}
.hero::after{content:'';position:absolute;bottom:-30%;left:-10%;width:400px;height:400px;background:radial-gradient(circle,rgba(245,158,11,.1) 0%,transparent 70%);border-radius:50%}
.hero-content{position:relative;z-index:1;max-width:720px}
.hero-badge{display:inline-flex;align-items:center;gap:6px;background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.15);padding:6px 16px;border-radius:50px;font-size:.8rem;font-weight:500;margin-bottom:20px;backdrop-filter:blur(4px)}
.hero h1{font-size:2rem;font-weight:800;line-height:1.2;margin-bottom:16px}
.hero h1 .accent{color:var(--amber-400)}
.hero p{font-size:1.05rem;color:rgba(255,255,255,.8);margin-bottom:28px;line-height:1.7}
.hero-ctas{display:flex;flex-wrap:wrap;gap:12px}

/* ── BUTTONS ── */
.btn{display:inline-flex;align-items:center;gap:8px;padding:12px 24px;border-radius:var(--radius-sm);font-weight:600;font-size:.95rem;min-height:44px;transition:var(--transition)}
.btn-primary{background:var(--blue-600);color:var(--white)}
.btn-primary:hover{background:var(--blue-500);color:var(--white);transform:translateY(-2px);box-shadow:0 4px 15px rgba(37,99,235,.4)}
.btn-secondary{background:rgba(255,255,255,.12);color:var(--white);border:1px solid rgba(255,255,255,.2)}
.btn-secondary:hover{background:rgba(255,255,255,.2);color:var(--white)}
.btn-amber{background:var(--amber-500);color:var(--navy-900)}
.btn-amber:hover{background:var(--amber-400);transform:translateY(-2px);box-shadow:0 4px 15px rgba(245,158,11,.4)}
.btn-outline{border:2px solid var(--blue-600);color:var(--blue-600)}
.btn-outline:hover{background:var(--blue-600);color:var(--white)}

/* ── SECTIONS ── */
.section{padding:60px 0}
.section-dark{background:var(--navy-900);color:var(--white)}
.section-gray{background:var(--gray-100)}
.section-header{text-align:center;margin-bottom:40px}
.section-header h2{font-size:1.75rem;font-weight:800;color:var(--navy-900);margin-bottom:12px}
.section-dark .section-header h2{color:var(--white)}
.section-header p{color:var(--gray-500);font-size:1.05rem;max-width:600px;margin:0 auto}
.section-dark .section-header p{color:rgba(255,255,255,.6)}
.section-label{display:inline-block;font-size:.8rem;font-weight:600;text-transform:uppercase;letter-spacing:1.5px;color:var(--blue-600);margin-bottom:8px}

/* ── CARDS GRID ── */
.cards-grid{display:grid;grid-template-columns:1fr;gap:20px}
.card{background:var(--white);border-radius:var(--radius-lg);padding:28px 24px;border:1px solid var(--gray-200);transition:var(--transition);position:relative;overflow:hidden}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--blue-400)}
.card-icon{width:48px;height:48px;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:1.5rem;margin-bottom:16px;background:linear-gradient(135deg,rgba(37,99,235,.1),rgba(37,99,235,.05))}
.card h3{font-size:1.15rem;font-weight:700;margin-bottom:8px;color:var(--navy-900)}
.card p{color:var(--gray-500);font-size:.9rem;line-height:1.6}
.card-link{display:inline-flex;align-items:center;gap:4px;margin-top:14px;font-weight:600;font-size:.875rem;color:var(--blue-600)}
.card-link:hover{gap:8px}

/* Dark cards */
.section-dark .card{background:rgba(255,255,255,.05);border-color:rgba(255,255,255,.1)}
.section-dark .card:hover{background:rgba(255,255,255,.1);border-color:var(--blue-400)}
.section-dark .card h3{color:var(--white)}
.section-dark .card p{color:rgba(255,255,255,.6)}

/* ── TOOL BLOCK ── */
.tool-block{background:linear-gradient(135deg,var(--blue-600),#1d4ed8);border-radius:var(--radius-xl);padding:40px 30px;color:var(--white);position:relative;overflow:hidden}
.tool-block::before{content:'';position:absolute;top:-50%;right:-20%;width:300px;height:300px;background:radial-gradient(circle,rgba(255,255,255,.08),transparent 70%);border-radius:50%}
.tool-block h2{font-size:1.5rem;font-weight:800;margin-bottom:10px;position:relative;z-index:1}
.tool-block p{color:rgba(255,255,255,.8);margin-bottom:20px;position:relative;z-index:1}

/* ── LATEST GUIDES ── */
.guides-list{display:grid;grid-template-columns:1fr;gap:16px}
.guide-item{display:flex;gap:16px;padding:20px;background:var(--white);border-radius:var(--radius-md);border:1px solid var(--gray-200);transition:var(--transition)}
.guide-item:hover{box-shadow:var(--shadow-md);border-color:var(--blue-400)}
.guide-number{min-width:40px;height:40px;border-radius:var(--radius-sm);background:linear-gradient(135deg,var(--blue-600),var(--blue-400));color:var(--white);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.9rem}
.guide-item h3{font-size:1rem;font-weight:600;margin-bottom:4px}
.guide-item p{font-size:.85rem;color:var(--gray-500)}

/* ── FOOTER ── */
.site-footer{background:var(--navy-900);color:rgba(255,255,255,.7);padding:50px 0 0}
.footer-grid{display:grid;grid-template-columns:1fr;gap:32px;padding-bottom:40px}
.footer-brand p{font-size:.9rem;line-height:1.7;margin-top:12px}
.footer-col h4{color:var(--white);font-size:.9rem;font-weight:700;margin-bottom:12px;text-transform:uppercase;letter-spacing:1px}
.footer-col a{display:block;padding:4px 0;font-size:.875rem;color:rgba(255,255,255,.6);transition:var(--transition)}
.footer-col a:hover{color:var(--amber-400);padding-left:4px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding:20px 0;text-align:center;font-size:.8rem;color:rgba(255,255,255,.4)}

/* ── BREADCRUMB ── */
.breadcrumb{padding:16px 0;font-size:.85rem}
.breadcrumb ol{display:flex;flex-wrap:wrap;gap:4px;align-items:center}
.breadcrumb li{display:flex;align-items:center;gap:4px;color:var(--gray-400)}
.breadcrumb li::after{content:'›';margin-left:4px;color:var(--gray-300)}
.breadcrumb li:last-child::after{display:none}
.breadcrumb li:last-child{color:var(--gray-600);font-weight:500}
.breadcrumb a{color:var(--gray-500)}
.breadcrumb a:hover{color:var(--blue-600)}

/* ── ARTICLE ── */
.article-header{padding:40px 0 20px}
.article-header h1{font-size:1.85rem;font-weight:800;color:var(--navy-900);line-height:1.3;margin-bottom:12px}
.article-meta{display:flex;flex-wrap:wrap;gap:16px;font-size:.85rem;color:var(--gray-500)}
.article-body{max-width:800px;padding-bottom:60px}
.article-body h2{font-size:1.4rem;font-weight:700;color:var(--navy-900);margin:36px 0 16px;padding-bottom:8px;border-bottom:2px solid var(--gray-200)}
.article-body h3{font-size:1.15rem;font-weight:600;color:var(--navy-800);margin:24px 0 12px}
.article-body p{margin-bottom:16px;color:var(--gray-700);line-height:1.8}
.article-body ul,.article-body ol{margin:12px 0 20px 20px}
.article-body li{margin-bottom:8px;color:var(--gray-700);line-height:1.7}
.article-body ul li{list-style:disc}
.article-body ol li{list-style:decimal}
.article-body strong{color:var(--navy-900);font-weight:600}
.article-body a{color:var(--blue-600);text-decoration:underline;text-decoration-color:rgba(37,99,235,.3);text-underline-offset:2px}
.article-body a:hover{text-decoration-color:var(--blue-600)}

/* ── TABLE OF CONTENTS ── */
.toc{background:var(--gray-100);border:1px solid var(--gray-200);border-radius:var(--radius-md);padding:20px 24px;margin:20px 0 32px}
.toc-title{display:flex;align-items:center;justify-content:space-between;font-weight:700;font-size:1rem;color:var(--navy-900);cursor:pointer}
.toc-title::after{content:'▾';font-size:.8rem;transition:var(--transition)}
.toc-title.collapsed::after{transform:rotate(-90deg)}
.toc-list{margin-top:12px}
.toc-list li{margin-bottom:6px}
.toc-list a{display:block;padding:6px 12px;font-size:.9rem;color:var(--gray-600);border-left:2px solid transparent;border-radius:0 var(--radius-sm) var(--radius-sm) 0;transition:var(--transition)}
.toc-list a:hover,.toc-list a.active{color:var(--blue-600);border-left-color:var(--blue-600);background:rgba(37,99,235,.05)}

/* ── TABLES ── */
.table-wrapper{overflow-x:auto;margin:20px 0;border-radius:var(--radius-md);border:1px solid var(--gray-200)}
table{width:100%;border-collapse:collapse}
thead{background:var(--navy-900);color:var(--white)}
th{padding:12px 16px;text-align:left;font-weight:600;font-size:.875rem}
td{padding:12px 16px;border-bottom:1px solid var(--gray-200);font-size:.9rem;color:var(--gray-700)}
tbody tr:hover{background:rgba(37,99,235,.03)}
tbody tr:nth-child(even){background:var(--gray-50)}

/* ── INTERNAL LINK BLOCKS ── */
.also-know{background:linear-gradient(135deg,rgba(37,99,235,.05),rgba(37,99,235,.02));border:1px solid rgba(37,99,235,.15);border-radius:var(--radius-md);padding:24px;margin:32px 0}
.also-know h3{font-size:1rem;font-weight:700;color:var(--blue-600);margin-bottom:12px}
.also-know ul{margin:0}
.also-know li{margin-bottom:8px;list-style:none!important;padding-left:0}
.also-know a{font-weight:500;text-decoration:none;display:flex;align-items:center;gap:6px}
.also-know a::before{content:'📌';font-size:.85rem}

.next-read{background:linear-gradient(135deg,var(--navy-900),var(--navy-700));border-radius:var(--radius-lg);padding:28px;margin:40px 0;color:var(--white)}
.next-read h3{font-size:1rem;margin-bottom:8px}
.next-read p{color:rgba(255,255,255,.7);margin-bottom:14px;font-size:.9rem}
.next-read a{color:var(--amber-400);font-weight:600;display:inline-flex;align-items:center;gap:4px}

/* ── FAQ ACCORDION ── */
.faq-section{margin:40px 0}
.faq-section h2{border:none!important}
.faq-item{border:1px solid var(--gray-200);border-radius:var(--radius-md);margin-bottom:8px;overflow:hidden}
.faq-question{display:flex;align-items:center;justify-content:space-between;width:100%;padding:16px 20px;font-size:1rem;font-weight:600;color:var(--navy-900);background:var(--white);text-align:left;transition:var(--transition);min-height:44px}
.faq-question:hover{background:var(--gray-50)}
.faq-question::after{content:'+';font-size:1.3rem;font-weight:300;color:var(--gray-400);transition:var(--transition)}
.faq-question.active{background:var(--gray-50)}
.faq-question.active::after{content:'−'}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .35s ease}
.faq-answer-inner{padding:0 20px 20px;color:var(--gray-600);line-height:1.7;font-size:.95rem}

/* ── CALCULATOR ── */
.calc-container{background:var(--white);border-radius:var(--radius-xl);border:1px solid var(--gray-200);padding:32px;box-shadow:var(--shadow-md)}
.calc-group{margin-bottom:20px}
.calc-group label{display:block;font-weight:600;font-size:.9rem;color:var(--navy-900);margin-bottom:8px}
.calc-group select,.calc-group input{width:100%;padding:12px 16px;border:1px solid var(--gray-300);border-radius:var(--radius-sm);font-size:1rem;font-family:var(--font-sans);transition:var(--transition);min-height:44px;background:var(--white)}
.calc-group select:focus,.calc-group input:focus{outline:none;border-color:var(--blue-600);box-shadow:0 0 0 3px rgba(37,99,235,.1)}
.calc-result{background:linear-gradient(135deg,var(--navy-900),var(--navy-700));border-radius:var(--radius-lg);padding:32px;color:var(--white);margin-top:24px;display:none}
.calc-result.visible{display:block;animation:fadeUp .5s ease}
.calc-total{font-size:2rem;font-weight:800;color:var(--amber-400);margin:8px 0}
.calc-breakdown{margin-top:16px}
.calc-breakdown-item{display:flex;justify-content:space-between;padding:8px 0;border-bottom:1px solid rgba(255,255,255,.1);font-size:.9rem}

/* ── COMPARISON TABLE ── */
.comparison-highlight{background:var(--green-500);color:var(--white);padding:2px 8px;border-radius:4px;font-size:.8rem;font-weight:600}

/* ── CLUSTER CARDS ── */
.cluster-cards{display:grid;grid-template-columns:1fr;gap:16px;margin:32px 0}
.cluster-card{display:flex;align-items:center;gap:16px;padding:20px;background:var(--white);border:1px solid var(--gray-200);border-radius:var(--radius-md);transition:var(--transition)}
.cluster-card:hover{border-color:var(--blue-400);box-shadow:var(--shadow-md);transform:translateY(-2px)}
.cluster-card-icon{min-width:44px;height:44px;border-radius:var(--radius-sm);background:var(--blue-600);color:var(--white);display:flex;align-items:center;justify-content:center;font-size:1.2rem}
.cluster-card h3{font-size:1rem;font-weight:600;color:var(--navy-900);margin-bottom:2px}
.cluster-card p{font-size:.85rem;color:var(--gray-500)}

/* ── DISCLAIMER ── */
.disclaimer{background:rgba(245,158,11,.08);border-left:4px solid var(--amber-500);padding:16px 20px;border-radius:0 var(--radius-sm) var(--radius-sm) 0;margin:24px 0;font-size:.875rem;color:var(--gray-600)}

/* ── ADSENSE PLACEHOLDER ── */
.ad-block{background:var(--gray-100);border:1px dashed var(--gray-300);border-radius:var(--radius-sm);padding:20px;text-align:center;margin:32px 0;color:var(--gray-400);font-size:.8rem;min-height:90px;display:flex;align-items:center;justify-content:center}

/* ── CHECKLIST ── */
.checklist li{display:flex;align-items:flex-start;gap:10px;padding:10px 0;border-bottom:1px solid var(--gray-100)}
.checklist li::before{content:'☐';font-size:1.1rem;color:var(--blue-600);min-width:20px}

/* ── ANIMATIONS ── */
@keyframes fadeUp{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}
.fade-in{opacity:0;transform:translateY(20px);transition:opacity .6s ease,transform .6s ease}
.fade-in.visible{opacity:1;transform:translateY(0)}

/* ── RESPONSIVE ── */
@media(min-width:640px){
  .hero h1{font-size:2.5rem}
  .cards-grid{grid-template-columns:repeat(2,1fr)}
  .guides-list{grid-template-columns:repeat(2,1fr)}
  .cluster-cards{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:repeat(2,1fr)}
}
@media(min-width:768px){
  .article-header h1{font-size:2.2rem}
  .section{padding:80px 0}
}
@media(min-width:1024px){
  .menu-toggle{display:none}
  .main-nav{display:block}
  .hero{padding:80px 0 70px}
  .hero h1{font-size:3rem}
  .cards-grid{grid-template-columns:repeat(3,1fr)}
  .footer-grid{grid-template-columns:2fr 1fr 1fr 1fr}
  .guides-list{grid-template-columns:repeat(3,1fr)}
  .cluster-cards{grid-template-columns:repeat(3,1fr)}
  .calc-container{padding:40px}
}

/* ── MOBILE TABLE RESPONSIVE ── */
@media(max-width:640px){
  .table-wrapper table,.table-wrapper thead,.table-wrapper tbody,.table-wrapper tr,.table-wrapper th,.table-wrapper td{display:block}
  .table-wrapper thead{position:absolute;top:-9999px;left:-9999px}
  .table-wrapper tr{margin-bottom:12px;border:1px solid var(--gray-200);border-radius:var(--radius-sm);overflow:hidden}
  .table-wrapper td{position:relative;padding:10px 16px 10px 45%;text-align:right;border-bottom:1px solid var(--gray-100)}
  .table-wrapper td::before{content:attr(data-label);position:absolute;left:16px;top:10px;font-weight:600;font-size:.8rem;color:var(--gray-500);text-transform:uppercase}
}