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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Arial, sans-serif;
    color: #263247;
    background-image: url("fondo.jpg");
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    background-repeat: no-repeat;
    min-height: 100vh;
}

header {
    background: linear-gradient(
        135deg,
        rgba(28, 57, 99, 0.85),
        rgba(91, 125, 169, 0.75)
    );

    color: white;
    text-align: center;
    padding: 45px 20px;
    border-bottom: 2px solid rgba(255, 255, 255, 0.5);
    backdrop-filter: blur(5px);
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: 2px;
    text-shadow: 2px 3px 8px rgba(0, 0, 0, 0.35);
}

nav {
    width: 90%;
    max-width: 1100px;
    margin: 25px auto;
    padding: 12px;

    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;

    background: rgba(28, 51, 83, 0.78);
    border: 1px solid rgba(255, 255, 255, 0.45);
    border-radius: 16px;
    backdrop-filter: blur(12px);

    box-shadow: 0 8px 25px rgba(12, 30, 55, 0.25);
}

nav a {
    color: #FFFFFF;
    text-decoration: none;
    padding: 12px 18px;
    display: block;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s ease;
}

nav > a:hover,
.dropdown > a:hover {
    background: rgba(174, 207, 245, 0.25);
    color: #DCEBFF;
    transform: translateY(-2px);
}

.dropdown {
    position: relative;
}

.submenu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 230px;
    padding: 8px;

    background: rgba(27, 48, 77, 0.96);
    border: 1px solid rgba(255, 255, 255, 0.35);
    border-radius: 12px;

    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(12px);
    z-index: 100;
}

.dropdown:hover .submenu {
    display: block;
}

.submenu a {
    padding: 11px 14px;
    font-size: 14px;
    border-radius: 7px;
}

.submenu a:hover {
    background: rgba(154, 190, 235, 0.25);
    color: #FFFFFF;
    padding-left: 20px;
}

main {
    width: 90%;
    max-width: 1000px;
    margin: 45px auto;
    min-height: 350px;
}

section {
    background: rgba(244, 248, 253, 0.91);
    padding: 35px;
    margin-bottom: 30px;

    border-radius: 18px;
    border: 1px solid rgba(255, 255, 255, 0.8);

    box-shadow: 0 10px 30px rgba(15, 35, 65, 0.25);
    backdrop-filter: blur(10px);
}

section h2 {
    color: #284C79;
    font-size: 1.8rem;
    margin-bottom: 25px;
    padding-bottom: 12px;
    border-bottom: 2px solid #A9C5E8;
}

article {
    background: rgba(255, 255, 255, 0.72);
    padding: 25px;
    border-radius: 14px;
    border-left: 5px solid #6E94C2;
}

article h3 {
    color: #34577F;
    font-size: 1.15rem;
    margin-top: 20px;
    margin-bottom: 8px;
}

article h3:first-child {
    margin-top: 0;
}

article p {
    color: #34445B;
    font-size: 1rem;
    line-height: 1.8;
    margin-bottom: 12px;
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
}

audio,
video {
    max-width: 100%;
    margin-top: 12px;
    border-radius: 10px;
}



footer {
    width: 90%;
    max-width: 1100px;
    margin: 50px auto 20px;
    padding: 22px;

    text-align: center;
    color: white;

    background: rgba(27, 49, 79, 0.85);
    border: 1px solid rgba(255, 255, 255, 0.35);
    border-radius: 14px;

    backdrop-filter: blur(10px);
    box-shadow: 0 6px 20px rgba(10, 25, 45, 0.25);
}

footer p {
    font-size: 15px;
    letter-spacing: 1px;
}


@media (max-width: 768px) {

    header {
        padding: 30px 15px;
    }

    header h1 {
        font-size: 1.8rem;
    }

    nav {
        width: 94%;
        flex-direction: column;
        align-items: stretch;
    }

    nav a {
        text-align: center;
    }

    .dropdown {
        width: 100%;
    }

    .submenu {
        position: static;
        width: 100%;
    }

    main {
        width: 94%;
        margin: 25px auto;
    }

    section {
        padding: 22px;
    }

    section h2 {
        font-size: 1.5rem;
    }

    article {
        padding: 18px;
    }

    footer {
        width: 94%;
    }

    body {
        background-attachment: scroll;
    }
}


@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    nav a,
    .submenu a {
        transition: none;
    }
}

nav {
    position: relative;
    z-index: 1000;
}

.dropdown {
    position: relative;
    z-index: 1001;
}

.submenu {
    position: absolute;
    z-index: 1002;
}

main {
    position: relative;
    z-index: 1;
}