:root {
    --primary: #007acc;
    --primary-dark: #005fa3;
    --bg-body: #f3f4f6;
    --bg-card: #ffffff;
    --bg-header: #1f2937;
    --text-main: #111827;
    --text-muted: #6b7280;
    --text-light: #f9fafb;
    --font-stack: system-ui, -apple-system, sans-serif;
    --radius: 8px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}


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

body {
    font-family: var(--font-stack);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

a { color: var(--primary); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--primary-dark); text-decoration: underline; }

.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1.5rem;
}


header {
    background-color: var(--bg-header);
    padding: 1rem 0;
    margin-bottom: 2rem;
}

nav {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
}

.spin {
    width: 400px;
    animation: spin 0.5s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}


.hamburger {
    display: none;
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
    color: white;
    padding: 0.5rem 1rem;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--radius);
    margin-bottom: 0.5rem;
    user-select: none;
}

.hamburger:hover {
    background-color: rgba(255,255,255,0.1);
}

nav ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
    padding: 0;
    margin: 0;
    width: 100%;
}

nav a {
    color: #d1d5db;
    font-weight: 600;
    padding: 0.5rem 0.8rem;
    border-radius: var(--radius);
    display: inline-block;
    transition: all 0.2s;
}

nav a:hover, nav a.active {
    color: white;
    background-color: var(--primary);
    text-decoration: none;
}

main { flex: 1; padding-bottom: 2rem; }

article {
    background-color: var(--bg-card);
    padding: 2.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

h1 { font-size: 2.0rem; margin-bottom: 1.5rem; border-bottom: 3px solid var(--primary); display: inline-block; }
h2 { font-size: 1.8rem; margin: 2rem 0 1rem 0; }
img { max-width: 100%; height: auto; border-radius: var(--radius); border: 1px solid #e5e7eb; }
figure { margin: 2rem 0; text-align: center; }


.grid-menu {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.card {
    background-color: var(--bg-body);
    padding: 1.5rem;
    border-radius: var(--radius);
    border: 1px solid #e5e7eb;
    transition: transform 0.2s;
    display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-5px); border-color: var(--primary); }
.card a { margin-top: 1rem; display: inline-block; padding: 0.5rem 1rem; background: var(--primary); color: white; border-radius: var(--radius); width: fit-content;}


.external-links {
    margin-top: 3rem;
    padding: 1.5rem;
    background-color: #eff6ff;
    border-left: 5px solid var(--primary);
}

footer { text-align: center; padding: 2rem; background-color: var(--bg-header); color: #9ca3af; margin-top: auto; }


@media (max-width: 600px) {
    /* Zobrazíme tlačítko */
    .hamburger {
        display: block;
    }

    /* Seznam odkazů v základu skryjeme */
    nav ul {
        display: none;
        flex-direction: column;
        align-items: center; /* Vycentrování položek menu pod sebou */
        width: 100%;
    }

    /* Třída .active se přidá JavaScriptem -> Zobrazí menu */
    nav ul.active {
        display: flex;
        animation: fadeIn 0.3s ease-in-out; /* Plynulé zobrazení */
    }

    nav a {
        display: block;
        width: 100%;
        text-align: center;
        padding: 0.8rem;
        border-bottom: 1px solid rgba(255,255,255,0.05);
    }
}

/* Jednoduchá animace pro objevení menu */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}