/* ==========================================================================
   Lectia — sistema de diseño compartido
   Estética editorial: papel cálido, tinta, bordó y latón.
   ========================================================================== */

:root {
    --ink: #16110e;
    --ink-soft: #2a211b;
    --ink-muted: #5f544a;
    --paper: #f6f1e7;
    --paper-deep: #ede5d4;
    --paper-line: #d9cfba;
    --white: #fffdf8;
    --oxblood: #7a1f2b;
    --oxblood-deep: #5d1621;
    --brass: #b08d57;
    --brass-soft: #d4b783;
    --ok: #2f6b4f;
    --danger: #a3262f;

    --font-display: 'Fraunces', 'Iowan Old Style', 'Georgia', serif;
    --font-text: 'Newsreader', 'Georgia', serif;
    --font-ui: 'Inter', system-ui, -apple-system, 'Segoe UI', sans-serif;

    --nav-h: 72px;
    --radius: 3px;
    --ease: cubic-bezier(.2, .7, .2, 1);
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
    font-family: var(--font-ui);
    font-size: 16px;
    line-height: 1.6;
    color: var(--ink);
    background: var(--paper);
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 400;
    line-height: 1.08;
    letter-spacing: -0.01em;
}

[hidden] { display: none !important; }

a { color: inherit; }
button { font: inherit; color: inherit; }
img, svg { display: block; max-width: 100%; }

:focus-visible { outline: 2px solid var(--oxblood); outline-offset: 3px; }

.sr-only {
    position: absolute; width: 1px; height: 1px; overflow: hidden;
    clip: rect(0 0 0 0); white-space: nowrap;
}

.wrap { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 32px; }

.eyebrow {
    font-family: var(--font-ui);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: .18em;
    text-transform: uppercase;
    color: var(--oxblood);
    display: inline-flex;
    align-items: center;
    gap: 12px;
}
.eyebrow::before { content: ''; width: 28px; height: 1px; background: currentColor; }

/* ---------- Botones ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 14px 26px;
    border: 1px solid transparent;
    border-radius: var(--radius);
    font-family: var(--font-ui);
    font-size: 14px;
    font-weight: 600;
    letter-spacing: .02em;
    text-decoration: none;
    cursor: pointer;
    transition: background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease), transform .25s var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { background: var(--oxblood); }
.btn-accent { background: var(--oxblood); color: var(--white); }
.btn-accent:hover { background: var(--oxblood-deep); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); }
.btn-light { background: var(--paper); color: var(--ink); }
.btn-light:hover { background: var(--brass-soft); }
.btn-ghost-light { background: transparent; color: var(--paper); border-color: rgba(246, 241, 231, .5); }
.btn-ghost-light:hover { background: var(--paper); color: var(--ink); }
.btn-sm { padding: 10px 18px; font-size: 13px; }
.btn[disabled] { opacity: .4; cursor: not-allowed; }

.link-arrow {
    font-weight: 600;
    font-size: 14px;
    text-decoration: none;
    border-bottom: 1px solid currentColor;
    padding-bottom: 2px;
    transition: color .2s;
}
.link-arrow:hover { color: var(--oxblood); }

/* ---------- Navegación ---------- */
.site-nav {
    position: fixed;
    inset: 0 0 auto 0;
    z-index: 1000;
    height: var(--nav-h);
    background: rgba(246, 241, 231, .88);
    backdrop-filter: blur(14px) saturate(1.2);
    -webkit-backdrop-filter: blur(14px) saturate(1.2);
    border-bottom: 1px solid var(--paper-line);
}
.site-nav__inner {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
}
.brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; }
.brand__mark {
    width: 34px; height: 34px;
    display: grid; place-items: center;
    background: var(--ink); color: var(--paper);
    font-family: var(--font-display);
    font-style: italic;
    font-size: 20px;
    border-radius: 2px;
}
.brand__name {
    font-family: var(--font-display);
    font-size: 24px;
    letter-spacing: -0.02em;
}
.site-nav__links { display: flex; gap: 36px; list-style: none; margin-left: auto; margin-right: 8px; }
.site-nav__links a {
    font-size: 14px; font-weight: 500; text-decoration: none; color: var(--ink-muted);
    padding: 6px 0; border-bottom: 1px solid transparent;
    transition: color .2s, border-color .2s;
}
.site-nav__links a:hover,
.site-nav__links a[aria-current="page"] { color: var(--ink); border-color: var(--ink); }

.nav-toggle {
    display: none;
    width: 42px; height: 42px;
    background: none; border: 1px solid var(--paper-line); border-radius: var(--radius);
    cursor: pointer;
    position: relative;
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
    content: ''; position: absolute; left: 11px; width: 18px; height: 1.5px; background: var(--ink);
    transition: transform .25s var(--ease), opacity .2s;
}
.nav-toggle span { top: 20px; }
.nav-toggle span::before { left: 0; top: -6px; }
.nav-toggle span::after { left: 0; top: 6px; }
.site-nav.is-open .nav-toggle span { background: transparent; }
.site-nav.is-open .nav-toggle span::before { transform: translateY(6px) rotate(45deg); }
.site-nav.is-open .nav-toggle span::after { transform: translateY(-6px) rotate(-45deg); }

/* variante oscura (biblioteca) */
.site-nav--dark {
    background: rgba(22, 17, 14, .82);
    border-bottom-color: rgba(246, 241, 231, .12);
    color: var(--paper);
}
.site-nav--dark .brand__mark { background: var(--paper); color: var(--ink); }
.site-nav--dark .site-nav__links a { color: rgba(246, 241, 231, .65); }
.site-nav--dark .site-nav__links a:hover,
.site-nav--dark .site-nav__links a[aria-current="page"] { color: var(--paper); border-color: var(--paper); }
.site-nav--dark .btn-primary { background: var(--paper); color: var(--ink); }
.site-nav--dark .btn-primary:hover { background: var(--brass-soft); }
.site-nav--dark .nav-toggle { border-color: rgba(246, 241, 231, .25); }
.site-nav--dark .nav-toggle span,
.site-nav--dark .nav-toggle span::before,
.site-nav--dark .nav-toggle span::after { background: var(--paper); }
.site-nav--dark.is-open .nav-toggle span { background: transparent; }

@media (max-width: 860px) {
    .wrap { padding: 0 20px; }
    .nav-toggle { display: block; margin-left: auto; }
    .site-nav__inner > .btn { display: none; }
    .site-nav__links {
        position: absolute; top: var(--nav-h); left: 0; right: 0;
        flex-direction: column; gap: 0; margin: 0;
        background: var(--paper);
        border-bottom: 1px solid var(--paper-line);
        padding: 8px 20px 20px;
        display: none;
    }
    .site-nav--dark .site-nav__links { background: var(--ink); }
    .site-nav.is-open .site-nav__links { display: flex; }
    .site-nav__links a { display: block; padding: 14px 0; border-bottom: 1px solid var(--paper-line); font-size: 16px; }
    .site-nav--dark .site-nav__links a { border-bottom-color: rgba(246, 241, 231, .12); }
}

/* ---------- Formularios ---------- */
.field { margin-bottom: 22px; }
.field label {
    display: block;
    margin-bottom: 8px;
    font-size: 12px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase;
    color: var(--ink-muted);
}
.input, .textarea {
    width: 100%;
    padding: 13px 14px;
    background: var(--white);
    border: 1px solid var(--paper-line);
    border-radius: var(--radius);
    font-family: var(--font-ui);
    font-size: 15px;
    color: var(--ink);
    transition: border-color .2s, box-shadow .2s;
}
.input::placeholder, .textarea::placeholder { color: #a39784; }
.input:focus, .textarea:focus {
    outline: none;
    border-color: var(--oxblood);
    box-shadow: 0 0 0 3px rgba(122, 31, 43, .12);
}
.textarea { resize: vertical; min-height: 220px; line-height: 1.6; font-family: var(--font-text); font-size: 16px; }

/* ---------- Toast ---------- */
.toast-region {
    position: fixed; right: 24px; bottom: 24px; z-index: 3000;
    display: flex; flex-direction: column; gap: 10px; pointer-events: none;
}
.toast {
    background: var(--ink); color: var(--paper);
    padding: 14px 20px; border-radius: var(--radius);
    font-size: 14px; font-weight: 500;
    border-left: 3px solid var(--brass);
    box-shadow: 0 12px 30px rgba(22, 17, 14, .25);
    animation: toast-in .35s var(--ease);
}
.toast--error { border-left-color: #e0626b; }
.toast.is-leaving { opacity: 0; transform: translateY(8px); transition: all .3s; }
@keyframes toast-in { from { opacity: 0; transform: translateY(12px); } }

/* ---------- Footer ---------- */
.site-footer { background: var(--ink); color: rgba(246, 241, 231, .7); padding: 72px 0 36px; }
.site-footer__grid {
    display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 48px;
    padding-bottom: 56px; border-bottom: 1px solid rgba(246, 241, 231, .12);
}
.site-footer .brand__name { color: var(--paper); }
.site-footer .brand__mark { background: var(--paper); color: var(--ink); }
.site-footer p { max-width: 36ch; margin-top: 20px; font-family: var(--font-text); font-size: 17px; line-height: 1.55; }
.site-footer h4 {
    font-family: var(--font-ui); font-size: 12px; font-weight: 600; letter-spacing: .16em; text-transform: uppercase;
    color: var(--brass-soft); margin-bottom: 18px;
}
.site-footer ul { list-style: none; display: grid; gap: 10px; }
.site-footer a { text-decoration: none; font-size: 15px; transition: color .2s; }
.site-footer a:hover { color: var(--paper); }
.site-footer__legal { padding-top: 28px; font-size: 13px; display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
@media (max-width: 700px) {
    .site-footer__grid { grid-template-columns: 1fr; gap: 36px; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}