/* ==========================================================================
   TenneT SPA — Sistema de diseño "Plano de ingeniería"
   La idea: una empresa de ingeniería informática comunicada con el
   vocabulario visual de un plano técnico — grillas, marcas de registro,
   cuadros de título y numeración de especificaciones — en vez de una
   plantilla corporativa genérica.
   ========================================================================== */

:root {
    --color-blueprint: #14213D;
    --color-blueprint-line: #2D4373;
    --color-paper: #F4F1E8;
    --color-paper-line: #D8D2C0;
    --color-ink: #1A1D24;
    --color-slate: #5A6478;
    --color-copper: #C9832E;
    --color-copper-dark: #A8691F;

    --font-display: 'Space Grotesk', 'Segoe UI', sans-serif;
    --font-body: 'Inter', 'Segoe UI', sans-serif;
    --font-mono: 'IBM Plex Mono', 'Consolas', monospace;

    --max-width: 1120px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    * { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}

body {
    margin: 0;
    font-family: var(--font-body);
    color: var(--color-ink);
    background: var(--color-paper);
    line-height: 1.55;
}

h1, h2, h3 {
    font-family: var(--font-display);
    font-weight: 600;
    line-height: 1.15;
    margin: 0 0 0.5em;
}

a { color: inherit; }

a:focus-visible, button:focus-visible, input:focus-visible,
textarea:focus-visible, label:focus-visible {
    outline: 2px solid var(--color-copper);
    outline-offset: 3px;
}

.eyebrow {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-copper-dark);
    margin: 0 0 0.9em;
}

.section-dark .eyebrow { color: var(--color-copper); }

/* --- Fondo tipo grilla de plano ------------------------------------- */

.drawing-sheet {
    position: relative;
    overflow: hidden;
    padding: 5.5rem 1.5rem;
    background-image:
        repeating-linear-gradient(to right, var(--color-paper-line) 0 1px, transparent 1px 88px),
        repeating-linear-gradient(to bottom, var(--color-paper-line) 0 1px, transparent 1px 88px);
    background-position: center top;
}

.section-dark.drawing-sheet {
    background-color: var(--color-blueprint);
    background-image:
        repeating-linear-gradient(to right, var(--color-blueprint-line) 0 1px, transparent 1px 88px),
        repeating-linear-gradient(to bottom, var(--color-blueprint-line) 0 1px, transparent 1px 88px);
    color: var(--color-paper);
}

/* Marcas de registro en las esquinas, como en un plano impreso */
.drawing-sheet::before,
.drawing-sheet::after {
    content: "+";
    position: absolute;
    top: 1.1rem;
    font-family: var(--font-mono);
    color: var(--color-slate);
    opacity: 0.6;
    font-size: 1rem;
}
.drawing-sheet::before { left: 1.1rem; }
.drawing-sheet::after { right: 1.1rem; }
.section-dark.drawing-sheet::before,
.section-dark.drawing-sheet::after { color: var(--color-paper); opacity: 0.35; }

.section, .hero { max-width: var(--max-width); margin: 0 auto; }
.section-content > *, .hero-inner > * { max-width: 720px; }

.section h2 { font-size: clamp(1.6rem, 3vw, 2.1rem); }
.section-lead { color: var(--color-slate); font-size: 1.05rem; }
.section-dark .section-lead { color: #C7CEE0; }

/* --- Header / navegación --------------------------------------------- */

.site-header {
    background: var(--color-blueprint);
    color: var(--color-paper);
    position: sticky;
    top: 0;
    z-index: 20;
    border-bottom: 1px solid var(--color-blueprint-line);
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0.9rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand { display: flex; align-items: center; gap: 0.6rem; text-decoration: none; color: inherit; }

.brand-mark-img {
    height: 32px;
    width: auto;
    display: block;
}

.brand-name {
    font-family: var(--font-display);
    font-weight: 700;
    letter-spacing: 0.02em;
}

.brand-suffix { color: var(--color-copper); font-weight: 500; }

.main-nav { display: flex; align-items: center; gap: 1.8rem; }

.main-nav a {
    text-decoration: none;
    font-size: 0.92rem;
    color: #D6DBE8;
}

.main-nav a:hover { color: var(--color-paper); }

.nav-cta {
    border: 1px solid var(--color-copper);
    color: var(--color-copper) !important;
    padding: 0.4rem 0.9rem;
}
.nav-cta:hover { background: var(--color-copper); color: var(--color-blueprint) !important; }

.nav-toggle, .nav-toggle-label { display: none; }

/* --- Hero -------------------------------------------------------------- */

.hero {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 2.5rem;
    align-items: end;
    padding-top: 6rem;
    padding-bottom: 6rem;
}

.hero h1 {
    font-size: clamp(2.1rem, 4.2vw, 3.1rem);
    color: var(--color-blueprint);
}

.hero-lead { font-size: 1.08rem; color: var(--color-slate); max-width: 46ch; }

.hero-actions { display: flex; gap: 0.9rem; margin-top: 1.6rem; flex-wrap: wrap; }

/* Ilustración de red decorativa en el hero (retoma la idea del isotipo:
   cubo + triángulo + puntos de conexión), a modo de textura de fondo */
.hero-network-bg {
    position: absolute;
    top: -60px;
    right: -80px;
    width: 560px;
    height: 560px;
    z-index: 0;
    pointer-events: none;
}

.hero-inner, .hero-title-block, .section-content { position: relative; z-index: 1; }

/* Misma familia de ilustración, reutilizada en la sección de contacto */
.contacto-network-bg {
    position: absolute;
    bottom: -70px;
    right: -70px;
    width: 460px;
    height: 460px;
    z-index: 0;
    pointer-events: none;
}

/* Trazado tipo circuito impreso para el fondo de Servicios */
.servicios-circuit-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 220px;
    z-index: 0;
    pointer-events: none;
}

/* Numeral gigante de fondo, para secciones claras (Conócenos, Referencias) */
.section-num-bg {
    position: absolute;
    top: -0.3em;
    right: -0.04em;
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: clamp(9rem, 22vw, 15rem);
    line-height: 1;
    color: var(--color-blueprint);
    opacity: 0.05;
    z-index: 0;
    pointer-events: none;
    user-select: none;
}

/* --- Íconos de servicio -------------------------------------------------- */

.spec-icon {
    width: 30px;
    height: 30px;
    margin-bottom: 1rem;
}

/* --- Sección "Conócenos": texto + foto --------------------------------- */

.about-grid {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 2.5rem;
    align-items: center;
    max-width: none;
}

.about-grid > * { max-width: none; }

.photo-placeholder {
    aspect-ratio: 4 / 3;
    overflow: hidden;
    border: 1px dashed var(--color-blueprint-line);
    background-image: repeating-linear-gradient(45deg, var(--color-paper-line) 0 1px, transparent 1px 14px);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    text-align: center;
    padding: 1.5rem;
}

.photo-placeholder .tb-label { font-family: var(--font-mono); font-size: 0.78rem; color: var(--color-copper-dark); letter-spacing: 0.08em; }
.photo-placeholder p { margin: 0; font-size: 0.85rem; color: var(--color-slate); max-width: 32ch; }

.photo-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* --- Botones ------------------------------------------------------------ */

.btn {
    display: inline-block;
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 0.95rem;
    padding: 0.75rem 1.4rem;
    text-decoration: none;
    border: 1px solid transparent;
    cursor: pointer;
    transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.btn-primary { background: var(--color-copper); color: var(--color-blueprint); }
.btn-primary:hover { background: var(--color-copper-dark); }

.btn-ghost { border-color: var(--color-blueprint); color: var(--color-blueprint); }
.btn-ghost:hover { background: var(--color-blueprint); color: var(--color-paper); }

.section-dark .btn-ghost { border-color: var(--color-paper); color: var(--color-paper); }
.section-dark .btn-ghost:hover { background: var(--color-paper); color: var(--color-blueprint); }

/* --- Cuadro de título (elemento distintivo, estilo plano técnico) ------ */

.title-block {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    border: 1px solid var(--color-blueprint);
    background: rgba(255, 255, 255, 0.55);
    align-self: end;
}

.title-block-row {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.45rem 0.7rem;
    border-top: 1px solid var(--color-paper-line);
}
.title-block-row:first-child { border-top: none; }

.tb-label { color: var(--color-slate); letter-spacing: 0.05em; }
.tb-value { color: var(--color-ink); font-weight: 500; }

.footer-block.title-block {
    background: transparent;
    border-color: var(--color-blueprint-line);
    color: var(--color-paper);
}
.footer-block.title-block .title-block-row { border-top-color: var(--color-blueprint-line); }
.footer-block.title-block .tb-label { color: #9FAAC4; }
.footer-block.title-block .tb-value { color: var(--color-paper); }

/* --- Servicios: fichas numeradas tipo lista de especificaciones -------- */

.spec-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1px;
    background: var(--color-blueprint-line);
    border: 1px solid var(--color-blueprint-line);
    max-width: none;
}

.spec-card {
    background: var(--color-blueprint);
    padding: 2rem 1.6rem;
    position: relative;
}

.spec-number {
    display: block;
    font-family: var(--font-mono);
    font-size: 2.2rem;
    color: var(--color-blueprint-line);
    margin-bottom: 0.6rem;
}

.spec-card h3 { color: var(--color-paper); font-size: 1.15rem; }
.spec-card p { color: #C7CEE0; font-size: 0.96rem; margin: 0; }

/* --- Clientes ------------------------------------------------------------ */

.client-legend {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 0.75rem;
}

.client-legend li {
    font-family: var(--font-mono);
    font-size: 0.88rem;
    border: 1px solid var(--color-blueprint);
    padding: 0.8rem 1rem;
    color: var(--color-blueprint);
}

/* --- Franja de estadísticas (entre el hero y Contacto) ------------------- */

.stats-strip {
    background: var(--color-paper);
    border-top: 1px solid var(--color-paper-line);
    border-bottom: 1px solid var(--color-paper-line);
    padding: 2rem 1.5rem;
}

.stats-strip-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    justify-content: center;
    gap: 3.5rem;
    flex-wrap: wrap;
    text-align: center;
}

.stat-num {
    display: block;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 2rem;
    color: var(--color-blueprint);
}

.stat-label {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--color-slate);
}

/* --- FAQ (acordeón nativo, sin JS) ---------------------------------------- */

.faq-list { margin-top: 1.5rem; }

.faq-item { border-bottom: 1px solid var(--color-paper-line); }

.faq-item summary {
    cursor: pointer;
    list-style: none;
    padding: 1.1rem 0;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1rem;
    color: var(--color-blueprint);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
    content: "+";
    font-family: var(--font-mono);
    color: var(--color-copper);
    font-size: 1.2rem;
    flex-shrink: 0;
}

.faq-item[open] summary::after { content: "\2212"; }

.faq-item p { margin: 0 0 1.2rem; color: var(--color-slate); font-size: 0.95rem; max-width: 70ch; }

.section-dark .faq-item { border-bottom-color: var(--color-blueprint-line); }
.section-dark .faq-item summary { color: var(--color-paper); }
.section-dark .faq-item p { color: #C7CEE0; }

/* --- Formulario de contacto ---------------------------------------------- */

.contact-form {
    max-width: 640px;
    margin-top: 1.5rem;
    background: rgba(16, 27, 51, 0.55);
    border: 1px solid var(--color-blueprint-line);
    padding: 1.75rem 2rem;
    border-radius: 3px;
}

.form-row { margin-bottom: 1.1rem; display: flex; flex-direction: column; gap: 0.35rem; }

.form-row-split { display: grid; grid-template-columns: 1fr 1fr; gap: 1.1rem; }
.form-row-split > div { display: flex; flex-direction: column; gap: 0.35rem; }

.contact-form label {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: #C7CEE0;
}

.contact-form input, .contact-form textarea {
    font-family: var(--font-body);
    font-size: 1rem;
    background: rgba(244, 241, 232, 0.07);
    border: 1px solid var(--color-blueprint-line);
    border-radius: 2px;
    color: var(--color-paper);
    padding: 0.7rem 0.85rem;
}

.contact-form input:focus, .contact-form textarea:focus {
    border-color: var(--color-copper);
    background: rgba(244, 241, 232, 0.11);
    outline: none;
}

.field-error { color: #F0A868; font-size: 0.82rem; min-height: 1.1em; }
.validation-summary { color: #F0A868; font-size: 0.9rem; }
.validation-summary ul { margin: 0; padding-left: 1.2rem; }

.alert-success {
    background: rgba(201, 131, 46, 0.15);
    border: 1px solid var(--color-copper);
    color: var(--color-paper);
    padding: 0.8rem 1rem;
    font-size: 0.92rem;
    margin-bottom: 1.2rem;
}

/* --- Footer ---------------------------------------------------------------- */

.site-footer { background: var(--color-blueprint); color: #C7CEE0; }

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 3.5rem 1.5rem 2rem;
    display: grid;
    grid-template-columns: 1.1fr 1fr 1fr;
    gap: 2.5rem;
}

.footer-heading {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-paper);
    margin-bottom: 0.8rem;
}

.footer-block p { margin: 0.3rem 0; font-size: 0.92rem; }
.footer-block a { text-decoration: none; }
.footer-block a:hover { color: var(--color-copper); }

.footer-bottom {
    border-top: 1px solid var(--color-blueprint-line);
    text-align: center;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    padding: 1.1rem;
    color: #8E99B5;
}

/* --- Responsive -------------------------------------------------------- */

@media (max-width: 860px) {
    .hero { grid-template-columns: 1fr; }
    .hero-title-block { justify-self: start; }
    .hero-network-bg { width: 340px; height: 340px; opacity: 0.6; top: -20px; right: -100px; }
    .about-grid { grid-template-columns: 1fr; }
    .footer-inner { grid-template-columns: 1fr; }

    .nav-toggle-label {
        display: block;
        cursor: pointer;
        width: 26px; height: 20px;
        position: relative;
    }
    .nav-toggle-label span,
    .nav-toggle-label span::before,
    .nav-toggle-label span::after {
        content: ""; position: absolute; left: 0;
        width: 100%; height: 2px; background: var(--color-paper);
    }
    .nav-toggle-label span { top: 9px; }
    .nav-toggle-label span::before { top: -8px; }
    .nav-toggle-label span::after { top: 8px; }

    .nav-toggle { display: none; }

    .main-nav {
        position: absolute;
        top: 100%; left: 0; right: 0;
        background: var(--color-blueprint);
        flex-direction: column;
        align-items: flex-start;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.2s ease;
    }
    .main-nav a { padding: 0.9rem 1.5rem; width: 100%; border-top: 1px solid var(--color-blueprint-line); }

    .nav-toggle:checked ~ .main-nav { max-height: 300px; }

    .form-row-split { grid-template-columns: 1fr; }
}