/* --- OSNOVNI STILOVI I RESPONSIVNOST --- */

:root {
    /* Definicija boja */
    --primary-color: #3498db; /* Svetlo plava */
    --text-color: #ffffff; /* Bela */
    --text-shadow-color: rgba(0, 0, 0, 0.4);
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
    height: 100vh;
    display: flex; /* Koristi flexbox za centriranje */
    justify-content: center;
    align-items: center;
    overflow: hidden; /* Sprečava pojavu scrollbar-a zbog animacije */
    background-color: #2c3e50; /* Tamno plava (fallback) */
}

/* Stil za centrirani sadržaj */
.content-center {
    z-index: 2; /* Osigurava da je tekst iznad pozadine */
    text-align: center;
}

.content-center h1 {
    font-size: 5em; /* Veliki natpis */
    color: var(--text-color);
    text-shadow: 2px 2px 4px var(--text-shadow-color);
    /* Responsivnost za manji ekran */
    padding: 10px;
}

/* Responsivnost: Smanji font na manjim ekranima (npr. mobilni telefoni) */
@media (max-width: 600px) {
    .content-center h1 {
        font-size: 3em;
    }
}


/* --- ANIMACIJA POZADINE: PLUTAJUĆI MEHURIĆI --- */

.background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom right, #2c3e50, var(--primary-color));
    z-index: 1; /* Postavlja pozadinu ispod teksta */
}

.bubbles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    list-style: none;
}

.bubbles li {
    position: absolute;
    display: block;
    list-style: none;
    width: 20px;
    height: 20px;
    background: rgba(255, 255, 255, 0.2); /* Prozirna bela */
    bottom: -150px;
    animation: animate 25s linear infinite;
    border-radius: 50%;
}

/* Dodela različitih pozicija, veličina i trajanja animacije svakom mehuriću */
.bubbles li:nth-child(1) {
    left: 25%;
    width: 80px;
    height: 80px;
    animation-delay: 0s;
}

.bubbles li:nth-child(2) {
    left: 10%;
    width: 20px;
    height: 20px;
    animation-delay: 2s;
    animation-duration: 12s;
}

.bubbles li:nth-child(3) {
    left: 70%;
    width: 20px;
    height: 20px;
    animation-delay: 4s;
}

.bubbles li:nth-child(4) {
    left: 40%;
    width: 60px;
    height: 60px;
    animation-delay: 0s;
    animation-duration: 18s;
}

.bubbles li:nth-child(5) {
    left: 65%;
    width: 20px;
    height: 20px;
    animation-delay: 0s;
}

.bubbles li:nth-child(6) {
    left: 75%;
    width: 110px;
    height: 110px;
    animation-delay: 3s;
}

.bubbles li:nth-child(7) {
    left: 35%;
    width: 150px;
    height: 150px;
    animation-delay: 7s;
}

.bubbles li:nth-child(8) {
    left: 50%;
    width: 25px;
    height: 25px;
    animation-delay: 15s;
    animation-duration: 45s;
}

.bubbles li:nth-child(9) {
    left: 20%;
    width: 15px;
    height: 15px;
    animation-delay: 2s;
    animation-duration: 35s;
}

.bubbles li:nth-child(10) {
    left: 85%;
    width: 150px;
    height: 150px;
    animation-delay: 0s;
    animation-duration: 11s;
}

/* Definicija CSS animacije */
@keyframes animate {
    0% {
        transform: translateY(0) rotate(0deg);
        opacity: 1;
        border-radius: 0;
    }

    100% {
        transform: translateY(-1000px) rotate(720deg);
        opacity: 0;
        border-radius: 50%;
    }
}