* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f5f7fa;
    color: #1f2937;
}

header {
    background: white;
    border-bottom: 1px solid #e5e7eb;
    padding: 24px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    margin: 0;
    font-size: 28px;
}

header p {
    margin: 6px 0 0;
    color: #6b7280;
}

button {
    border: none;
    border-radius: 8px;
    padding: 12px 18px;
    font-size: 15px;
    cursor: pointer;
    background: #111827;
    color: white;
}

button:hover {
    opacity: 0.88;
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 35px 30px;
}

.pretraga input {
    width: 100%;
    padding: 15px 18px;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    font-size: 16px;
    outline: none;
    background: white;
}

.pretraga input:focus {
    border-color: #6b7280;
}

.statistika {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
    margin-top: 25px;
}

.kartica {
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    padding: 22px;
}

.kartica span {
    display: block;
    color: #6b7280;
    margin-bottom: 10px;
}

.kartica strong {
    font-size: 30px;
}

.znanje {
    margin-top: 40px;
}

.znanje h2 {
    margin-bottom: 18px;
}

.prazno {
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    padding: 55px 25px;
    text-align: center;
}

.prazno h3 {
    margin-top: 0;
}

.prazno p {
    color: #6b7280;
    margin-bottom: 0;
}

@media (max-width: 700px) {
    header {
        padding: 20px;
    }

    main {
        padding: 25px 18px;
    }

    .statistika {
        grid-template-columns: 1fr;
    }
}