/* =========================================================
   YTR Ingenieros Consultores — hoja de estilos
   Paleta: naranja ladrillo (logo), gris carbón, hueso, blanco
   ========================================================= */

:root {
    --naranja: #b0540e;
    --naranja-osc: #8d4209;
    --carbon: #2b302e;
    --carbon-suave: #454c49;
    --hueso: #f4f2ef;
    --blanco: #ffffff;
    --linea: #e0dcd6;
    --texto: #2b302e;
    --texto-suave: #6b7370;
    --radio: 2px;
    --max: 1160px;
}

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

html { scroll-behavior: smooth; background: var(--blanco); }

body {
    margin: 0;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--texto);
    background: var(--blanco);
    -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

h1, h2, h3 {
    font-family: 'Archivo', 'Inter', sans-serif;
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.12;
    margin: 0;
}

h1 { font-size: clamp(2.1rem, 5.5vw, 3.8rem); }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.5rem); }
h3 { font-size: 1.125rem; letter-spacing: -0.01em; }

p { margin: 0 0 1rem; }
a { color: inherit; text-decoration: none; }

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

.skip-link {
    position: absolute; left: -9999px; top: 0; z-index: 100;
    background: var(--carbon); color: var(--blanco); padding: 0.75rem 1rem;
}
.skip-link:focus { left: 0; }

.container {
    width: 100%;
    max-width: var(--max);
    margin: 0 auto;
    padding: 0 1.25rem;
}

.eyebrow {
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    font-weight: 600;
    color: var(--naranja);
    margin: 0 0 1rem;
}

/* ---------- Botones ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    background: var(--naranja);
    color: var(--blanco);
    padding: 0.85rem 1.6rem;
    border: 1px solid var(--naranja);
    border-radius: var(--radio);
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.btn:hover { background: var(--naranja-osc); border-color: var(--naranja-osc); }

.btn-ghost {
    background: transparent;
    color: var(--blanco);
    border-color: rgba(255, 255, 255, 0.55);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); border-color: var(--blanco); }

.btn-sm { padding: 0.6rem 1.1rem; font-size: 0.75rem; }
.btn-block { width: 100%; }

/* ---------- Header ---------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: var(--blanco);
    border-bottom: 1px solid var(--linea);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    min-height: 74px;
}

.brand img { width: 108px; height: auto; }

.nav { display: flex; align-items: center; gap: 2rem; }
.nav ul {
    display: flex;
    gap: 1.75rem;
    list-style: none;
    margin: 0;
    padding: 0;
}
.nav a {
    font-size: 0.82rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--carbon-suave);
    padding-bottom: 2px;
    border-bottom: 2px solid transparent;
}
.nav ul a:hover { color: var(--naranja); border-bottom-color: var(--naranja); }

.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    background: none;
    border: 1px solid var(--linea);
    border-radius: var(--radio);
    cursor: pointer;
}
.nav-toggle-bar {
    display: block;
    width: 20px;
    height: 2px;
    margin: 0 auto;
    background: var(--carbon);
}

/* ---------- Hero ---------- */
.hero {
    position: relative;
    background: var(--carbon);
    color: var(--blanco);
    overflow: hidden;
}
.hero-media { position: absolute; inset: 0; }
.hero-media img { width: 100%; height: 100%; object-fit: cover; opacity: 0.4; }
.hero::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, rgba(43,48,46,0.94) 0%, rgba(43,48,46,0.72) 55%, rgba(43,48,46,0.45) 100%);
}
.hero-inner {
    position: relative;
    z-index: 2;
    padding: 5.5rem 1.25rem 5rem;
    max-width: 900px;
    margin: 0 auto;
}
.hero .eyebrow { color: #e59355; }
.hero-text {
    font-size: 1.075rem;
    color: rgba(255, 255, 255, 0.82);
    max-width: 46ch;
    margin-top: 1.25rem;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2rem; }

/* ---------- Indicadores ---------- */
.stats { background: var(--naranja); color: var(--blanco); }
.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
}
.stat {
    padding: 1.75rem 1.25rem;
    border-left: 1px solid rgba(255, 255, 255, 0.24);
}
.stat:nth-child(2n + 1) { border-left: none; }
.stat-value {
    display: block;
    font-family: 'Archivo', sans-serif;
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}
.stat-label {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: rgba(255, 255, 255, 0.85);
    margin-top: 0.35rem;
}

/* ---------- Secciones ---------- */
.section { padding: 4.5rem 0; }
.section-alt { background: var(--hueso); }
.section-dark { background: var(--carbon); color: var(--blanco); }

.section-head { max-width: 40ch; margin-bottom: 2.75rem; }

/* ---------- Tarjetas de servicio ---------- */
.cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1px;
    background: var(--linea);
    border: 1px solid var(--linea);
}
.card {
    background: var(--blanco);
    padding: 2rem 1.75rem;
    transition: background 0.2s ease;
}
.card:hover { background: var(--hueso); }
.card-num {
    display: block;
    font-family: 'Archivo', sans-serif;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--naranja);
    margin-bottom: 1.25rem;
}
.card h3 { margin-bottom: 0.6rem; }
.card p { color: var(--texto-suave); font-size: 0.94rem; margin: 0; }

/* ---------- Nosotros ---------- */
.about { display: grid; gap: 2rem; }
.about-text p { color: rgba(255, 255, 255, 0.78); }

.check-list {
    list-style: none;
    margin: 1.75rem 0 0;
    padding: 0;
    display: grid;
    gap: 0.75rem;
}
.check-list li {
    position: relative;
    padding-left: 1.75rem;
    font-size: 0.94rem;
    color: rgba(255, 255, 255, 0.9);
}
.check-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.55rem;
    width: 10px;
    height: 10px;
    background: var(--naranja);
}

/* ---------- Proyectos ---------- */
.projects {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2.5rem;
}
.project-media {
    aspect-ratio: 4 / 3;
    overflow: hidden;
    background: var(--hueso);
    margin-bottom: 1.25rem;
}
.project-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}
.project:hover .project-media img { transform: scale(1.04); }
.project-tag {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.18em;
    font-weight: 600;
    color: var(--naranja);
    margin-bottom: 0.5rem;
}
.project h3 { margin-bottom: 0.35rem; }
.project-detail { font-size: 0.9rem; color: var(--texto-suave); margin: 0; }

/* ---------- Contacto ---------- */
.contact { display: grid; gap: 3rem; }
.contact-info p { color: var(--texto-suave); max-width: 44ch; }

.contact-data {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.5rem;
    margin: 2rem 0 0;
}
.contact-data dt {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    font-weight: 600;
    color: var(--texto-suave);
    margin-bottom: 0.3rem;
}
.contact-data dd { margin: 0; font-size: 0.95rem; font-weight: 500; }
.contact-data a:hover { color: var(--naranja); }

.form-wrap {
    background: var(--blanco);
    border: 1px solid var(--linea);
    padding: 1.75rem;
}

.field { margin-bottom: 1.1rem; }
.field-row { display: grid; gap: 1.1rem; }

label {
    display: block;
    font-size: 0.78rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--carbon-suave);
    margin-bottom: 0.4rem;
}

input, select, textarea {
    width: 100%;
    font-family: inherit;
    font-size: 0.95rem;
    color: var(--texto);
    background: var(--blanco);
    padding: 0.75rem 0.85rem;
    border: 1px solid var(--linea);
    border-radius: var(--radio);
}
input:focus, select:focus, textarea:focus {
    outline: 2px solid var(--naranja);
    outline-offset: 1px;
    border-color: var(--naranja);
}
textarea { resize: vertical; }

.field-error {
    display: block;
    font-size: 0.8rem;
    color: #b3261e;
    margin-top: 0.35rem;
}

.form-note { font-size: 0.78rem; color: var(--texto-suave); margin: 0.9rem 0 0; }

.hp { position: absolute; left: -9999px; }

.alert {
    padding: 0.9rem 1rem;
    margin-bottom: 1.25rem;
    font-size: 0.9rem;
    border-left: 3px solid;
}
.alert strong { display: block; }
.alert-ok { background: #eef4ee; border-color: #2f7d43; color: #1f4d2b; }
.alert-error { background: #fdeeed; border-color: #b3261e; color: #8c1d18; }

/* ---------- Footer ---------- */
.site-footer {
    background: var(--carbon);
    color: rgba(255, 255, 255, 0.8);
    padding: 3.5rem 0 1.5rem;
}
.footer-grid { display: grid; gap: 2.5rem; }
.footer-brand img {
    width: 110px;
    height: auto;
    background: var(--blanco);
    padding: 0.4rem;
}
.footer-brand p { font-size: 0.9rem; max-width: 34ch; margin-top: 1rem; }

.footer-title {
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.18em;
    color: var(--blanco);
    margin-bottom: 1rem;
}
.footer-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.55rem; font-size: 0.9rem; }
.footer-list a:hover { color: #e59355; }

.footer-bottom {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 0.5rem;
    margin-top: 3rem;
    padding-top: 1.25rem;
    border-top: 1px solid rgba(255, 255, 255, 0.14);
    font-size: 0.78rem;
    color: rgba(255, 255, 255, 0.55);
}
.footer-bottom p { margin: 0; }

/* ---------- WhatsApp flotante ---------- */
.whatsapp-float {
    position: fixed;
    right: 1rem;
    bottom: 1rem;
    z-index: 60;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 52px;
    height: 52px;
    background: #25d366;
    color: #fff;
    border-radius: 50%;
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.22);
}
.whatsapp-float:hover { background: #1eb955; }

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 860px) {
    .nav-toggle { display: flex; }

    .nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        background: var(--blanco);
        border-bottom: 1px solid var(--linea);
        padding: 0.5rem 1.25rem 1.5rem;
    }
    .nav.is-open { display: flex; }
    .nav ul { flex-direction: column; gap: 0; }
    .nav ul li { border-bottom: 1px solid var(--linea); }
    .nav ul a { display: block; padding: 0.9rem 0; border-bottom: none; }
    .nav .btn { margin-top: 1rem; }

    .header-inner { position: relative; }
}

@media (min-width: 640px) {
    .field-row { grid-template-columns: 1fr 1fr; }
    .cards { grid-template-columns: 1fr 1fr; }
    .projects { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 900px) {
    .section { padding: 6rem 0; }
    .hero-inner { padding: 8rem 1.25rem 7rem; max-width: var(--max); }
    .stats-grid { grid-template-columns: repeat(4, 1fr); }
    .stat { border-left: 1px solid rgba(255, 255, 255, 0.24); }
    .stat:first-child { border-left: none; }
    .cards { grid-template-columns: repeat(4, 1fr); }
    .projects { grid-template-columns: repeat(3, 1fr); }
    .about { grid-template-columns: 1fr 1.2fr; gap: 4rem; }
    .contact { grid-template-columns: 1fr 1fr; gap: 4rem; align-items: start; }
    .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; gap: 3rem; }
    .form-wrap { padding: 2.25rem; }
}