/* =========================
   Química — celda de tabla periódica + cuaderno de laboratorio
   Fondo claro de banco de laboratorio, serif editorial para el cuerpo,
   monoespaciada para los datos numéricos de la celda de elemento.
   ========================= */

:root {
    --lab-bg: #f6f8f6;
    --lab-ink: #1e2a24;
    --lab-muted: #5b6b62;
    --lab-green: #059669;
    --lab-green-light: #d7f3e8;
    --lab-amber: #d97706;
    --lab-border: #d8ded9;
}

* {
    box-sizing: border-box;
}


/* ANIMACION DE ENTRADA: reaccion en el matraz */

@keyframes chemFill {
    from { transform: scaleY(0); }
    to { transform: scaleY(1); }
}

.chem-liquid {
    transform-box: fill-box;
    transform-origin: bottom;
    animation: chemFill 1s ease-out .3s both;
}

@keyframes chemBubble {
    0% { transform: translateY(0); opacity: 0; }
    15% { opacity: 1; }
    100% { transform: translateY(-24px); opacity: 0; }
}

.chem-bubble {
    transform-box: fill-box;
    transform-origin: center;
    animation: chemBubble 2.4s ease-in infinite;
}

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

.chem-draw {
    stroke-dasharray: 1;
    stroke-dashoffset: 1;
    animation: chemDraw .4s ease forwards;
}

@media (prefers-reduced-motion: reduce) {
    .chem-liquid { animation: none; transform: scaleY(1); }
    .chem-bubble { animation: none; opacity: 0; }
    .chem-draw { animation: none; stroke-dashoffset: 0; }
}

body.lab {
    margin: 0;
    background-color: var(--lab-bg);
    background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='64' height='56'><polygon points='16,0 48,0 64,28 48,56 16,56 0,28' fill='none' stroke='%23059669' stroke-opacity='0.09' stroke-width='1.2'/></svg>");
    background-position: 0 0;
    color: var(--lab-ink);
    font-family: "Source Serif 4", Georgia, serif;
}

a {
    color: var(--lab-green);
}

a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--lab-amber);
    outline-offset: 2px;
}


/* BARRA SUPERIOR */

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

    padding: 24px 40px;
    border-bottom: 1px solid var(--lab-border);
    font-family: "IBM Plex Sans", sans-serif;
}

.lab-brand {
    text-decoration: none;
    color: var(--lab-ink);
    font-weight: 600;
}

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

.lab-nav a {
    text-decoration: none;
    color: var(--lab-muted);
    font-size: 14px;
}

.lab-nav a:hover {
    color: var(--lab-green);
}


/* CONTENIDO */

.lab-main {
    max-width: 720px;
    margin: 0 auto;
    padding: 56px 24px 80px;
}

.lab-main > * + * {
    margin-top: 44px;
}


/* BANNER ILUSTRADO (solo en la cabecera) */

.lab-banner {
    position: relative;
    overflow: hidden;
    background: linear-gradient(160deg, #0d1f1a, #123526);
    min-height: 320px;
    display: flex;
    align-items: center;
}

.lab-banner-svg {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

.lab-banner-text {
    position: relative;
    max-width: 720px;
    margin: 0 auto;
    padding: 0 40px;
    text-align: center;
}

.lab-banner-text h1 {
    font-family: "Source Serif 4", Georgia, serif;
    font-size: 44px;
    color: #eafff3;
    margin: 0 0 14px;
}

.lab-banner-text p {
    margin: 0 auto;
    color: #b7cec2;
    font-size: 16px;
    line-height: 1.65;
    max-width: 480px;
}


/* BUSCADOR */

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

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

    padding: 10px 16px;

    background-color: #fff;
    border: 1.5px solid var(--lab-border);
    border-radius: 3px;

    color: var(--lab-ink);
    font-family: "IBM Plex Sans", sans-serif;
    font-size: 15px;
}

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

.lab-search:focus {
    outline: none;
    border-color: var(--lab-green);
}


/* SECCIONES */

.lab-section-title {
    display: flex;
    align-items: center;
    gap: 10px;

    font-family: "Source Serif 4", Georgia, serif;
    font-size: 21px;
    font-weight: 600;
    color: var(--lab-ink);
    margin: 0 0 16px;
}

.lab-section-title::before {
    content: "";
    width: 10px;
    height: 10px;
    background-color: var(--lab-green);
    transform: rotate(45deg);
    flex: 0 0 auto;
}

.lab-rows {
    border-top: 1px solid var(--lab-border);
}

.lab-row {
    position: relative;
    display: flex;
    align-items: flex-start;
    gap: 16px;

    padding: 16px 16px 16px 16px;
    color: var(--lab-ink);
    border-left: 4px solid var(--lab-green);
    border-bottom: 1px solid var(--lab-border);
    background-color: white;

    transition: background-color 0.12s ease;
}

.lab-row-link {
    position: absolute;
    inset: 0;
    z-index: 1;
}

.lab-row:hover {
    background-color: var(--lab-green-light);
}

.lab-row-index {
    flex: 0 0 auto;
    width: 34px;
    height: 34px;
    border: 1.5px solid var(--lab-green);
    border-radius: 3px;

    display: flex;
    align-items: center;
    justify-content: center;

    font-family: "IBM Plex Mono", monospace;
    font-size: 13px;
    font-weight: 600;
    color: var(--lab-green);
    background-color: var(--lab-green-light);
}

.lab-row-text {
    flex: 1;
}

.lab-row h3 {
    margin: 0 0 4px;
    font-size: 18px;
    font-weight: 600;
}

.lab-row p {
    margin: 0;
    font-family: "IBM Plex Sans", sans-serif;
    color: var(--lab-muted);
    font-size: 14px;
}

.lab-row-meta {
    flex: 0 0 auto;
    font-family: "IBM Plex Mono", monospace;
    font-size: 12px;
    color: var(--lab-amber);
    white-space: nowrap;
}

.lab-row-copy {
    position: relative;
    z-index: 2;
    flex: 0 0 auto;

    width: 26px;
    height: 26px;
    padding: 0;

    background-color: white;
    border: 1.5px solid var(--lab-green);
    border-radius: 3px;

    color: var(--lab-green);
    font-size: 12px;
    line-height: 1;
    cursor: pointer;
    transition: background-color 0.12s ease;
}

.lab-row-copy:hover {
    background-color: var(--lab-green-light);
}

.lab-empty {
    font-family: "IBM Plex Sans", sans-serif;
    color: var(--lab-muted);
    font-size: 14px;
    font-style: italic;
    padding: 16px;
    border: 1px dashed var(--lab-border);
}


@media (max-width: 640px) {

    .lab-row {
        flex-wrap: wrap;
    }

    .lab-row-meta {
        margin-left: 50px;
    }

    .lab-row-copy {
        margin-left: 8px;
    }

    .lab-topbar {
        padding: 20px 20px;
    }

    .lab-main {
        padding: 40px 20px 60px;
    }

    .lab-banner {
        min-height: 240px;
    }

    .lab-banner-text h1 {
        font-size: 32px;
    }

    .lab-banner-text p {
        max-width: none;
    }

}