:root {
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-secondary: #10b981;
    --color-dark: #1e293b;
    --color-text: #334155;
    --color-light: #f8fafc;
    --color-border: #e2e8f0;
    --color-white: #ffffff;
    --color-error: #ef4444;
    --font-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --container-width: 1100px;
    --radius: 8px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --transition: all 0.2s ease-in-out;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: var(--font-base); color: var(--color-text); background-color: var(--color-light); line-height: 1.6; display: flex; flex-direction: column; min-height: 100vh; }
h1, h2, h3, h4 { color: var(--color-dark); font-weight: 700; line-height: 1.2; margin-bottom: 1rem; }
h1 { font-size: 2.5rem; } h2 { font-size: 2rem; } h3 { font-size: 1.5rem; }
p { margin-bottom: 1rem; }
a { color: var(--color-primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--color-primary-hover); text-decoration: underline; }
.container { width: 100%; max-width: var(--container-width); margin: 0 auto; padding: 0 1.5rem; }
main { flex: 1; padding: 3rem 0; }
.header { background-color: var(--color-white); border-bottom: 1px solid var(--color-border); position: sticky; top: 0; z-index: 100; }
.nav-container { display: flex; justify-content: space-between; align-items: center; height: 70px; }
.logo { font-size: 1.5rem; font-weight: 800; color: var(--color-primary); text-decoration: none; }
.logo:hover { text-decoration: none; }
.logo span { color: var(--color-secondary); }
.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a { color: var(--color-dark); font-weight: 500; }
.nav-links a:hover { color: var(--color-primary); text-decoration: none; }
.mobile-menu-btn { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; color: var(--color-dark); }
.hero { text-align: center; padding: 4rem 0; background: linear-gradient(to bottom, #ffffff, var(--color-light)); border-bottom: 1px solid var(--color-border); }
.hero p { font-size: 1.2rem; color: var(--color-text); max-width: 600px; margin: 0 auto 2rem; }
.btn { display: inline-block; padding: 0.75rem 1.5rem; background-color: var(--color-primary); color: var(--color-white); border-radius: var(--radius); font-weight: 600; border: none; cursor: pointer; text-decoration: none; text-align: center; }
.btn:hover { background-color: var(--color-primary-hover); color: var(--color-white); text-decoration: none; }
.btn-outline { background-color: transparent; border: 2px solid var(--color-primary); color: var(--color-primary); }
.btn-outline:hover { background-color: var(--color-primary); color: var(--color-white); }
.section-title { text-align: center; margin-bottom: 3rem; }
.tools-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 2rem; margin-bottom: 4rem; }
.card { background-color: var(--color-white); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 1.5rem; box-shadow: var(--shadow); transition: var(--transition); display: flex; flex-direction: column; }
.card:hover { transform: translateY(-5px); box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1); }
.card-icon { font-size: 2.5rem; margin-bottom: 1rem; }
.card h3 { margin-bottom: 0.5rem; font-size: 1.25rem; }
.card p { flex: 1; font-size: 0.95rem; color: #64748b; }
.card-link { margin-top: 1rem; font-weight: 600; display: inline-flex; align-items: center; }
.ad-placeholder { width: 100%; background-color: #f1f5f9; border: 1px dashed #cbd5e1; display: flex; align-items: center; justify-content: center; color: #94a3b8; font-size: 0.85rem; margin: 2rem 0; min-height: 90px; text-align: center; border-radius: 4px; }
.ad-placeholder::before { content: "Espacio reservado para publicidad"; }
.footer { background-color: var(--color-dark); color: var(--color-white); padding: 3rem 0 1rem; margin-top: auto; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 2rem; margin-bottom: 2rem; }
.footer h4 { color: var(--color-white); font-size: 1.1rem; }
.footer a { color: #94a3b8; }
.footer a:hover { color: var(--color-white); text-decoration: none; }
@media (max-width: 768px) {
    .nav-links { display: none; flex-direction: column; position: absolute; top: 70px; left: 0; width: 100%; background-color: var(--color-white); padding: 1rem; box-shadow: 0 4px 6px -1px rgba(0,0,0,0.1); border-bottom: 1px solid var(--color-border); }
    .nav-links.active { display: flex; }
    .mobile-menu-btn { display: block; }
    h1 { font-size: 2rem; }
}