/* Professional Expertise Tree Styles */
.expertise-tree-container {
    background: transparent;
    border: none;
    border-radius: 0;
    padding: 0;
    margin: 3rem auto;
    overflow: visible;
    min-height: 700px;
    position: relative;
    width: 100%;
    max-width: 1200px;
    max-height: none;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Elegant loading state */
.expertise-tree-container:empty::before {
    content: "Loading expertise visualization...";
    color: #9ca3af;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-style: italic;
    font-size: 0.9rem;
    letter-spacing: 0.5px;
}

/* D3.js Tree Styling */
#expertiseTree {
    width: 100%;
    height: 100%;
    min-height: 600px;
    overflow: visible;
    display: flex;
    justify-content: center;
    align-items: center;
}

#expertiseTree svg {
    width: 100%;
    height: 100%;
    min-height: 600px;
    background: transparent;
    overflow: visible;
    display: block;
    margin: 0 auto;
    shape-rendering: geometricPrecision;
    font-smooth: always;
    -webkit-font-smoothing: antialiased;
}

/* Professional node styling */
.node {
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.node circle {
    fill: #10b981;
    stroke: #ffffff;
    stroke-width: 1.5px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    shape-rendering: geometricPrecision;
    filter: none;
}

.node:hover circle {
    stroke-width: 2px;
    filter: url(#glow);
}

.node text {
    font-family: 'Inter', 'SF Pro Display', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: 10px;
    fill: #ffffff;
    font-weight: 500;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.8);
    pointer-events: none;
    letter-spacing: 0.2px;
    opacity: 0.9;
}

.node:hover text {
    font-weight: 600;
    opacity: 1;
}

/* Elegant link styling */
.link {
    fill: none;
    stroke: url(#gradient);
    stroke-width: 1.2px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    shape-rendering: geometricPrecision;
    stroke-linecap: round;
    opacity: 0.4;
}

.link:hover {
    opacity: 0.8;
    stroke-width: 1.8px;
}

/* Smooth animations */
.link-updating {
    stroke-dasharray: 1000;
    stroke-dashoffset: 1000;
    animation: elegantDraw 2s ease-in-out forwards;
}

@keyframes elegantDraw {
    to {
        stroke-dashoffset: 0;
    }
}

/* Professional responsive design */
@media (max-width: 768px) {
    .expertise-tree-container {
        margin: 2rem auto;
        min-height: 500px;
        max-height: none;
        padding: 0 1rem;
    }

    #expertiseTree,
    #expertiseTree svg {
        min-height: 450px;
    }

    .node text {
        font-size: 9px;
        letter-spacing: 0.1px;
    }
}

@media (max-width: 480px) {
    .expertise-tree-container {
        min-height: 450px;
        max-height: none;
        margin: 1.5rem auto;
        padding: 0 0.75rem;
    }

    #expertiseTree,
    #expertiseTree svg {
        min-height: 400px;
    }

    .node text {
        font-size: 8px;
    }

    .node circle {
        stroke-width: 1px;
    }
}

/* Smooth transitions for all tree elements */
#expertiseTree g,
#expertiseTree path,
#expertiseTree circle,
#expertiseTree text {
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Firefox-specific professional improvements */
@-moz-document url-prefix() {
    .expertise-tree-container {
        transform: translateZ(0);
    }

    #expertiseTree svg {
        filter: none;
    }

    .link {
        stroke-linejoin: round;
    }

    .node text {
        text-rendering: geometricPrecision;
    }
}

/* Enhanced focus states for accessibility */
.node:focus {
    outline: none;
}

.node:focus circle {
    stroke: #ffffff;
    stroke-width: 3px;
    filter: url(#glow);
}

/* Subtle background pattern for depth */
.expertise-tree-container::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(circle at 20% 80%, rgba(16, 185, 129, 0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(59, 130, 246, 0.03) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}