/* =========================
   Matemáticas — estética de pizarra
   Fondo verde pizarra con marco de madera, tipografía de tiza a mano
   (Caveat) para títulos y una sans redondeada (Nunito) para el cuerpo.
   ========================= */

:root {
    --board-bg: #1c2b22;
    --board-frame: #5c4130;
    --board-frame-light: #7a5940;
    --chalk: #f4f1e8;
    --chalk-muted: #b9c2b6;
    --chalk-yellow: #f2d675;
    --chalk-blue: #8ecae6;
    --chalk-pink: #f4a6b7;
}

* {
    box-sizing: border-box;
}

body.board {
    margin: 0;
    background-color: var(--board-frame);
    color: var(--chalk);
    font-family: "Nunito", -apple-system, "Segoe UI", sans-serif;
}

.board-display {
    font-family: "Caveat", cursive;
}

a {
    color: var(--chalk);
}

a:focus-visible,
button:focus-visible {
    outline: 3px solid var(--chalk-yellow);
    outline-offset: 3px;
}


/* MARCO DE MADERA */

.board-frame {
    border: 18px solid var(--board-frame);
    border-top-color: var(--board-frame-light);
    border-left-color: var(--board-frame-light);
    background-color: var(--board-bg);
    min-height: 100vh;
}

.board-tray {
    height: 14px;
    background: linear-gradient(to bottom, #3a2a1e, #2a1d15);
    box-shadow: inset 0 4px 8px rgba(0, 0, 0, 0.4);
}


/* BARRA SUPERIOR */

.board-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;

    padding: 24px 40px 0;
}

.board-brand {
    font-family: "Caveat", cursive;
    font-size: 28px;
    font-weight: 700;
    text-decoration: none;
    color: var(--chalk);
}

.board-nav {
    display: flex;
    flex-wrap: wrap;
    row-gap: 8px;
    gap: 18px;
}

.board-nav a {
    text-decoration: none;
    color: var(--chalk-muted);
    font-size: 16px;
}

.board-nav a:hover {
    color: var(--chalk);
}


/* CONTENIDO */

.board-main {
    max-width: 820px;
    margin: 0 auto;
    padding: 40px 32px 90px;
}

.board-main > * + * {
    margin-top: 48px;
}


/* HERO */

.board-hero {
    text-align: center;
}

.board-hero h1 {
    font-family: "Caveat", cursive;
    font-size: 76px;
    font-weight: 700;
    margin: 0;
    line-height: 1;
}

.board-underline {
    display: block;
    width: 220px;
    height: 22px;
    margin: 4px auto 18px;
}

.board-hero p {
    max-width: 520px;
    margin: 0 auto;
    color: var(--chalk-muted);
    font-size: 17px;
    line-height: 1.6;
}


/* ANIMACION DE ENTRADA: tiza escribiendose */

@keyframes chalkWrite {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes chalkDraw {
    from { stroke-dashoffset: 1; }
    to { stroke-dashoffset: 0; }
}

.chalk-write {
    opacity: 0;
    animation: chalkWrite 0.5s ease forwards;
}

.board-hero h1.chalk-write {
    animation-delay: 0.15s;
}

.chalk-draw {
    stroke-dasharray: 1;
    stroke-dashoffset: 1;
    animation: chalkDraw 0.6s ease forwards;
}

@media (prefers-reduced-motion: reduce) {
    .chalk-write, .chalk-draw {
        animation: none;
        opacity: 1;
        stroke-dashoffset: 0;
    }
}


/* ICONOS DECORATIVOS */

.board-doodles {
    display: flex;
    justify-content: center;
    gap: 56px;
    opacity: 0.85;
}


/* SECCIONES */

.board-section-title {
    font-family: "Caveat", cursive;
    font-size: 34px;
    margin: 0 0 20px;
    color: var(--chalk-yellow);
}


/* BUSCADOR */

.board-search-form {
    margin-bottom: 8px;
}

.board-search {
    width: 100%;
    max-width: 420px;

    padding: 10px 16px;

    background-color: transparent;
    border: 2px dashed rgba(244, 241, 232, 0.45);
    border-radius: 20px;

    color: var(--chalk);
    font-family: "Nunito", sans-serif;
    font-size: 15px;
}

.board-search::placeholder {
    color: var(--chalk-muted);
}

.board-search:focus {
    outline: none;
    border-color: var(--chalk-yellow);
}

.board-cards {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.board-card {
    position: relative;
    display: block;
    color: var(--chalk);
    border: 2px dashed rgba(244, 241, 232, 0.45);
    border-radius: 3px;
    padding: 18px 22px;
    transform: rotate(-0.6deg);
    transition: transform 0.15s ease, border-color 0.15s ease;
}

.board-cards > *:nth-child(even) {
    transform: rotate(0.5deg);
}

.board-card:hover {
    border-color: var(--chalk-yellow);
    transform: rotate(0deg);
}

.board-card-link {
    position: absolute;
    inset: 0;
    z-index: 1;
}

.board-card h3 {
    font-family: "Caveat", cursive;
    font-size: 26px;
    font-weight: 700;
    margin: 0 0 4px;
    padding-right: 40px;
}

.board-card p {
    margin: 0;
    color: var(--chalk-muted);
    font-size: 15px;
}

.board-card .board-meta {
    display: inline-block;
    margin-top: 8px;
    color: var(--chalk-blue);
    font-size: 13px;
}

.board-card-copy {
    position: absolute;
    z-index: 2;
    top: 14px;
    right: 14px;

    width: 30px;
    height: 30px;
    padding: 0;

    background-color: transparent;
    border: 1.5px dashed rgba(244, 241, 232, 0.45);
    border-radius: 50%;

    color: var(--chalk-blue);
    font-size: 14px;
    line-height: 1;
    cursor: pointer;
    transition: border-color 0.15s ease, color 0.15s ease;
}

.board-card-copy:hover {
    border-color: var(--chalk-yellow);
    color: var(--chalk-yellow);
}

.board-empty {
    font-family: "Caveat", cursive;
    font-size: 22px;
    color: var(--chalk-yellow);
    opacity: 0.9;
}


@media (max-width: 640px) {

    .board-topbar {
        padding: 20px 20px 0;
    }

    .board-main {
        padding: 32px 20px 70px;
    }

    .board-hero h1 {
        font-size: 56px;
    }

    .board-doodles {
        gap: 28px;
    }

    .board-doodles svg {
        width: 44px;
        height: 44px;
    }

}