/* ==================== CSS VARIABLES ==================== */
:root {
    /* Colors */
    --color-primary: #000000;
    --color-background: #ffffff;
    --color-border: #B2BEB5;
    --color-link: inherit;
    --color-hover: #333333;
    --color-modal-bg: rgba(0, 0, 0, 0.9);
    
    /* Typography */
    --font-primary: 'Calibri', sans-serif;
    --font-fallback: 'Times New Roman', serif;
    --font-size-h1: 30pt;
    --font-size-h2: 15pt;
    --font-size-body: 12pt;
    --font-size-small: 11pt;
    
    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 20px;
    --spacing-lg: 30px;
    --spacing-xl: 46px;
    
    /* Layout */
    --profile-img-size: 175px;
    --content-width: 50%;
    --border-radius: 50%;
    
    /* Animation */
    --transition-speed: 0.3s;
}

/* ==================== BASE STYLES ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-fallback);
    font-size: var(--font-size-body);
    line-height: 1.6;
    color: var(--color-primary);
    background-color: var(--color-background);
}

a {
    color: var(--color-link);
    text-decoration: underline;
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--color-hover);
}

/* ==================== LAYOUT ==================== */
.portfolio {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.portfolio__center {
    text-align: center;
}

/* ==================== HEADER SECTION ==================== */
.header {
    margin-top: var(--spacing-lg);
}

.header__profile {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    padding: var(--spacing-sm);
}

.header__info {
    text-align: right;
    max-width: 500px;
}

.header__name {
    font-family: var(--font-primary);
    font-size: var(--font-size-h1);
    margin-bottom: var(--spacing-xs);
}

.header__title {
    font-family: var(--font-primary);
    font-size: var(--font-size-body);
    margin-bottom: var(--spacing-md);
    letter-spacing: 0.5px;
}

.header__contact {
    font-family: var(--font-primary);
    font-size: var(--font-size-small);
    margin: var(--spacing-md) 0;
}

.header__links {
    font-family: var(--font-primary);
    font-size: var(--font-size-body);
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    flex-wrap: wrap;
}

.header__image {
    width: var(--profile-img-size);
    height: var(--profile-img-size);
    border-radius: var(--border-radius);
    object-fit: cover;
    object-position: 50% 30%;
    border: 1px solid var(--color-border);
}


/* ==================== NAVIGATION ==================== */
.nav {
    margin-top: calc(var(--spacing-lg) - 4px);
}

.nav__list {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
    list-style: none;
}

.nav__item {
    font-family: var(--font-primary);
    font-size: var(--font-size-h2);
    cursor: pointer;
    padding-bottom: 4px;
    border-top: 2px solid transparent;
    transition: all var(--transition-speed);

    color: #9a9a9a;
}

.nav__item:hover {
    text-decoration: underline;
    color: #555555;
}

.nav__item--active {
    border-top-color: var(--color-primary);
    color: var(--color-primary);
    cursor: default;
    font-weight: 600;
}

.nav__item--active:hover {
    text-decoration: none;
}

/* ==================== CONTENT SECTIONS ==================== */
.content {
    width: var(--content-width);
    margin: 0 auto;
    margin-top: var(--spacing-md);
    text-align: left;
    display: none;
}

.content--active {
    display: block;
}

.content__text {
    line-height: 1.8;
}

/* ==================== PROJECTS ==================== */
.project {
    margin-top: var(--spacing-lg);
}

.project:first-of-type {
    margin-top: var(--spacing-md);
}

.project__title {
    font-size: 1.2em;
    margin-bottom: var(--spacing-sm);
}

.project__content {
    margin-top: var(--spacing-md);
}

.project__image {
    width: 200px;
    height: auto;
    float: right;
    margin-left: var(--spacing-md);
    cursor: pointer;
    transition: transform var(--transition-speed);
    border: 1px solid var(--color-border);
}

.project__image:hover {
    transform: scale(1.02);
}

.project__text {
    line-height: 1.8;
}

.project__footer {
    clear: both;
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-sm);
}

/* ==================== RESEARCH ==================== */
.research__item {
    margin-top: var(--spacing-md);
}

.research__title {
    font-size: 1.2em;
    margin-bottom: var(--spacing-sm);
}

.research__text {
    line-height: 1.8;
}

/* ==================== TEAM ==================== */
.team__list {
    list-style-position: inside; /* keeps bullets aligned with text block */
    padding-left: 0;             /* remove default indent */
    margin-top: 1rem;
}

.team__name {
    margin-bottom: 0.6rem;
    font-weight: 500;
}


/* ==================== MODAL ==================== */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: var(--color-modal-bg);
    align-items: center;
    justify-content: center;
}

.modal--active {
    display: flex;
}

.modal__content {
    margin: auto;
    display: block;
    max-width: 80%;
    max-height: 80vh;
    animation: modalZoom 0.6s;
}

.modal__close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: color var(--transition-speed);
    cursor: pointer;
    user-select: none;
}

.modal__close:hover,
.modal__close:focus {
    color: #bbb;
}

@keyframes modalZoom {
    from { transform: scale(0); }
    to { transform: scale(1); }
}




/* ==================== RESPONSIVE DESIGN ==================== */
@media (max-width: 768px) {
    :root {
        --font-size-h1: 24pt;
        --font-size-h2: 13pt;
        --profile-img-size: 120px;
        --content-width: 90%;
    }

    .header__profile {
        flex-direction: column;
        text-align: center;
    }

    .header__info {
        text-align: center;
    }

    .header__links {
        justify-content: center;
    }

    .nav__list {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .project__image {
        float: none;
        display: block;
        margin: var(--spacing-md) auto;
        width: 100%;
        max-width: 300px;
    }

    .modal__content {
        max-width: 95%;
    }

    .modal__close {
        top: 10px;
        right: 15px;
        font-size: 30px;
    }
}

/* ==================== UTILITY CLASSES ==================== */
.u-hide {
    display: none !important;
}

.u-show {
    display: block !important;
}

.u-text-center {
    text-align: center;
}

.u-mt-sm {
    margin-top: var(--spacing-sm);
}

.u-mt-md {
    margin-top: var(--spacing-md);
}