:root {
    /* Main Colors */
    --color-primary: #edc7b7;
    --color-secondary: #EEE2DC;
    --color-tertiary: #BAB2B2;
    --color-quaternary: #123c69;
    --color-quinary: #ac3b61;
    --color-text: #222;
    --color-text-alt: #fff;
    --color-headline: #111;

    /* Main Color Accents */
    --color-primary-accent-1:#cdab9c;
    --color-tertiary-accent-1: #EEE2DC;
    --color-quaternary-accent-1: #123c69d1;

    /* Utility Colors */
    --color-link: #337ab7;
    --color-link-hover: #0077cc;
    --color-btn: #222;
    --color-btn-hover: #444;
    --color-btn-link-hover: #337ab7;
    --color-seperator: #ddd;
}

/* Basic Styles for body and containers*/
body {
    font-family: 'Inter', Arial, sans-serif;
    background: var(--color-secondary);
    color: var(--color-text);
    margin: 0;
    padding: 0;
    line-height: 1.7;
}

/* Header Styles */
header {
    background: var(--color-quaternary);
    color: var(--color-secondary);
    padding: 1rem 0 0.5rem 0;
    text-align: center;
}

.header-inner h1 {
    margin: 0;
    font-size: 2.5rem;
    font-weight: 600;
}

.subtitle {
    font-size: 1.2rem;
    color: var(--color-secondary);
    margin-top: 0.5rem;
    font-weight: 400;
}

/* Main Content Sections */
main {
    padding: 3rem 0 0 0;
}

.main-grid {
    columns: 2; /* Two columns for a desktop layout */
    column-gap: 2rem;
    max-width: 90%;
    margin: 0 auto;
    padding: 0 2rem;
    box-sizing: border-box;
}

.container {
    break-inside: avoid; 
    position: relative;
    margin-bottom: 2rem;
    background: var(--color-primary);
    border-radius: 8px;
    padding: 1.2rem 1.5rem;
    border: 1px solid var(--color-primary-accent-1);
    box-shadow: none;
}


/* Headings and Links */
a {
    color: var(--color-link);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

h2 {
    color: var(--color-quaternary);
    font-size: 1.5rem;
    margin-bottom: 1.2rem;
    font-weight: 600;
    letter-spacing: 0.5px;
}

/* Details Button */
.details-button, .download-button {
    background: var(--color-quaternary); 
    color: var(--color-secondary);
    text-decoration: none;
    font-weight: 600;
    display: inline-block; 
    margin: 1rem;
    transition: background 0.2s;
    padding: 0.5rem 1rem;
}

.details-button:hover, .download-button:hover {
    background: var(--color-quaternary-accent-1); 
    color: var(--color-secondary);
    text-decoration: none;
}



/* CV Section */
.cv-section {
    margin-bottom: 1rem;
}

.cv-section h3 {
    margin-top: 0;
    font-size: 1.1rem;
    color: var(--color-quaternary-accent-1);
}

.cv-profile-photo {
    width: clamp(80px, 15vw, 150px);
    aspect-ratio: 1 / 1;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid var(--color-primary, #4A90E2);
    outline: 2px solid var(--color-quaternary, #ECEFF1);
    outline-offset: -6px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2), 
                0 0 0 1px rgba(0, 0, 0, 0.05);
    position: absolute;
    top: 1.5rem;
    right: 5%;
    z-index: 10;
}

.cv-list {
    list-style: none;
    padding: 0;
    margin: 0.5rem 0 0 0;
}

.cv-list li {
    margin-bottom: 0.7rem;
    line-height: 1.6;
}

.cv-separator {
    border: none;
    border-top: 1px solid var(--color-seperator);
    margin: 0.5rem 0;
    width: 50%;
    opacity: 0.7;
}

.skills {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.2rem 1.5rem;
}

.skills li {
    /* Kept display: inline-block for its wrapping behavior */
    display: inline-block;
    background: var(--color-primary-accent-1);
    border-radius: 4px;
    padding: 0.3rem 0.7rem;
    margin: 0.2rem 0.4rem 0.2rem 0;
    font-size: 0.95rem;
}

/* Working Papers Section */
.paper-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    align-items: stretch;
    width: 100%;
}

.paper-item {
    background: var(--color-primary-accent-1);
    padding: 1rem 1.2rem;
    /* Changed border-left to use a variable */
    border-left: 3px solid var(--color-quaternary);
    text-align: left;
    border-radius: 4px;
    /* Removed unused color variables and consolidated border/shadow */
    border: 1px solid var(--color-primary-accent-1);
    box-shadow: none;
}

.paper-item h3 {
    margin: 0 0 0.3rem 0;
    font-size: 1.05rem;
    color: var(--color-text);
    font-weight: 600;
}

.paper-item p {
    margin: 0 0 0.5rem 0;
    font-size: 0.99rem;
    color: var(--color-text);
}


/* Visualizations Section */
.visualization-list {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.visualization-preview {
    width: 45%;
    height: auto;
    object-fit: cover;
    border-radius: 6px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
    background: var(--color-primary);
}

/* Link hover for Presentations section */
.link-hover {
    color: var(--color-link);
    text-decoration: none;
    font-weight: 500;
    margin-top: 0.5rem;
    display: inline-block;
}

.link-hover:hover {
    text-decoration: underline;
}

/* Buttons */
.btn {
    display: inline-block;
    background: var(--color-btn);
    color: var(--color-text-alt);
    padding: 0.6rem 1.2rem;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    margin-top: 1rem;
    transition: background 0.2s;
}

.btn:hover {
    background: var(--color-btn-hover);
}

.github-btn {
    background: var(--color-btn);
}

.github-btn:hover {
    background: var(--color-btn-link-hover);
}

.fab {
    margin-right: 6px;
}

/* Footer */
footer {
    background: var(--color-quaternary);
    color: var(--color-text-alt);
    text-align: center;
    padding: 1rem 0;
    font-size: 0.95rem;
    margin-top: 2rem;
}

/* Hamburger Button */
.hamburger-btn {
    position: absolute; 
    top: 20px;
    left: 20px;
    z-index: 1000;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0px;
}

.hamburger-btn .bar {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--color-secondary);
    margin: 5px 0;
    transition: 0.4s;
}

.sidebar {
    position: fixed;
    top: 0;
    left: -250px;
    width: 250px;
    height: 100%;
    background-color: var(--color-secondary);
    padding-top: 60px;
    transition: 0.4s;
    z-index: 999;
    box-shadow: 2px 0 5px rgba(0,0,0,0.5);
    display: flex;
    flex-direction: column;
}

.sidebar a {
    padding: 15px;
    text-decoration: none;
    /* Changed color to a contrast value, as --color-footer-text is white and sidebar-bg is near white */
    color: var(--color-text);
    font-size: 1.2em;
    display: block;
    transition: 0.2s;
}

.sidebar a:hover {
    background-color: var(--color-quaternary);
    color: var(--color-text-alt); /* Makes text white on hover */
}

.sidebar.open {
    left: 0;
}

/* --- Styles for Nested Sub-Menu (Networks) --- */

/* Ensures the main link (Networks) is styled like the others, 
   and correctly wraps the submenu content */
.nav-item-with-submenu {
    display: flex;
    flex-direction: column;
}

/* Style the main Networks link inside the wrapper */
.nav-item-with-submenu > a {
    width: 100%;
    box-sizing: border-box;
}

/* Style the Submenu (the list of sub-links) */
.submenu {
    list-style: none;
    padding: 0;
    margin: 0;
    
    /* Initially hide the submenu using max-height */
    max-height: 0; 
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    background-color: var(--color-tertiary-accent-1);
}

/* Style the individual sub-menu items */
.submenu li a {
    padding: 10px 15px 10px 30px; /* Increased left padding for indentation */
    font-size: 1em;
    color: var(--color-text);
    background-color: transparent;
}

.submenu li a:hover {
    background-color: var(--color-quaternary-accent-1);
    color: var(--color-text-alt);
}

/* Submenu Toggle Behavior: shows the submenu when the parent has the 'open' class */
.nav-item-with-submenu.open .submenu {
    max-height: 500px; /* Large enough value to ensure all sublinks are visible */
}