:root {
    --brand-navy: #262F59;
    --brand-teal: #12A7CD; /* turkuaz */
    --brand-gold: #B99C71;
    --brand-orange: #EF7F1A;
    --brand-gray: #727271;
    /* convenience aliases used in styles */
    --navy: var(--brand-navy);
    --turkuaz: var(--brand-teal);
    --gold: var(--brand-gold);
    --orange: var(--brand-orange);
    --grey: var(--brand-gray);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
}

body {
    margin: 0;
    background: #f6f8fb;
    color: var(--navy);
}

.container {
    max-width: 1100px;
    margin: 0 auto
}

h1 {
    font-size: 20px;
    margin: 0 0 12px
}


/* Tree layout */
.tree {
    display: flex;
    justify-content: center
}

.node {
    position: relative;
    display: inline-block;
    text-align: center;
    vertical-align: top;
    margin: 16px
}

    .node .card {
        background: white;
        border: 2px solid var(--navy);
        padding: 10px 14px;
        border-radius: 10px;
        min-width: 160px;
        box-shadow: 0 6px 18px rgba(38,47,89,0.06)
    }

    .node .title {
        font-weight: 700;
        color: var(--navy);
        font-size: 14px
    }

    .node .subtitle {
        font-size: 12px;
        color: var(--grey);
        margin-top: 6px
    }


    /* lines */
    .node:before, .node:after {
        content: '';
        position: absolute
    }
    /* vertical line to parent */
    .node:before {
        width: 2px;
        height: 16px;
        left: 50%;
        top: -16px;
        background: var(--navy)
    }
/* horizontal connector between siblings */
.children {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    margin-top: 20px
}

    .children .node {
        margin: 0 12px
    }

    .children:before {
        /*content: '';*/
        position: absolute;
        left: 0;
        right: 0;
        top: 0;
        height: 2px;
        background: var(--navy)
    }


/* collapse control */
.toggle {
    display: inline-block;
    margin-left: 8px;
    background: var(--turkuaz);
    color: white;
    border-radius: 100%;
    width: 20px;
    height: 20px;
    line-height: 20px;
    font-size: 12px;
    cursor: pointer
}


/* controls */
.controls {
    display: flex;
    gap: 8px;
    margin: 12px 0 18px
}

button {
    background: var(--navy);
    color: white;
    padding: 8px 12px;
    border-radius: 8px;
    border: 0;
    cursor: pointer
}

input, textarea, select {
    padding: 8px;
    border-radius: 8px;
    border: 1px solid #ddd
}


/* responsive */
@media (max-width:720px) {
    .node .card {
        min-width: 140px
    }
}


/* Ana (root) düğümlerin üstündeki dikey çizgiyi kaldırır */
.tree > .children > .node:before {
    display: none;
}