/* ==========================================================================
   Patrick Heindel, MD, MPH - Portfolio Website Styles
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Custom Properties (Variables)
   -------------------------------------------------------------------------- */
:root {
    /* Light Mode Colors (Default) */
    --color-bg: #fafafa;
    --color-bg-secondary: #f4f4f4;
    --color-text: #1a1a2e;
    --color-text-secondary: #4a4a5e;
    --color-accent: #0066cc;
    --color-accent-hover: #004499;
    --color-accent-light: rgba(0, 102, 204, 0.1);
    --color-border: #e0e0e0;
    --color-code-bg: #f4f4f4;
    --color-shadow: rgba(0, 0, 0, 0.1);
    --color-shadow-lg: rgba(0, 0, 0, 0.15);

    /* Typography */
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    /* Font Sizes */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* Header Height */
    --header-height: 70px;
}

/* Dark Mode Colors */
[data-theme="dark"] {
    --color-bg: #1a1a2e;
    --color-bg-secondary: #252538;
    --color-text: #e8e8e8;
    --color-text-secondary: #a0a0b0;
    --color-accent: #4da6ff;
    --color-accent-hover: #6db8ff;
    --color-accent-light: rgba(77, 166, 255, 0.15);
    --color-border: #3a3a4e;
    --color-code-bg: #252538;
    --color-shadow: rgba(0, 0, 0, 0.3);
    --color-shadow-lg: rgba(0, 0, 0, 0.4);
}

/* --------------------------------------------------------------------------
   Base Styles
   -------------------------------------------------------------------------- */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    transition: background-color var(--transition-base), color var(--transition-base);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Skip Link for Accessibility */
.skip-link {
    position: absolute;
    top: -100%;
    left: 0;
    background: var(--color-accent);
    color: white;
    padding: var(--space-3) var(--space-4);
    z-index: 1000;
    text-decoration: none;
    font-weight: 500;
}

.skip-link:focus {
    top: 0;
}

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-4);
}

@media (min-width: 768px) {
    .container {
        padding: 0 var(--space-8);
    }
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-mono);
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-text);
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Accent Color */
.accent {
    color: var(--color-accent);
}

/* Terminal-style text */
.terminal-text {
    font-family: var(--font-mono);
    color: var(--color-accent);
}

.terminal-prompt {
    color: var(--color-accent);
    font-family: var(--font-mono);
    margin-right: var(--space-2);
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn--primary {
    background-color: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
}

.btn--primary:hover {
    background-color: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
    color: white;
}

.btn--secondary {
    background-color: transparent;
    color: var(--color-accent);
    border-color: var(--color-accent);
}

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

.btn--full {
    width: 100%;
}

/* --------------------------------------------------------------------------
   Header & Navigation
   -------------------------------------------------------------------------- */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    z-index: 100;
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.nav__logo {
    font-family: var(--font-mono);
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-text);
    text-decoration: none;
}

.nav__logo:hover {
    color: var(--color-text);
}

.nav__logo-text {
    display: flex;
    align-items: center;
}

/* Mobile Navigation Toggle */
.nav__toggle {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    width: 28px;
    height: 24px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 110;
}

.nav__toggle-bar {
    width: 100%;
    height: 3px;
    background-color: var(--color-text);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(2) {
    opacity: 0;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* Navigation Menu */
.nav__menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    background-color: var(--color-bg);
    border-left: 1px solid var(--color-border);
    padding: calc(var(--header-height) + var(--space-8)) var(--space-6) var(--space-8);
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    transition: right var(--transition-base), background-color var(--transition-base);
    z-index: 105;
}

.nav__menu.active {
    right: 0;
}

.nav__link {
    font-family: var(--font-mono);
    font-size: var(--text-base);
    color: var(--color-text);
    text-decoration: none;
    padding: var(--space-2) 0;
    display: block;
    transition: color var(--transition-fast);
}

.nav__link:hover {
    color: var(--color-accent);
}

/* Desktop Navigation */
@media (min-width: 768px) {
    .nav__toggle {
        display: none;
    }

    .nav__menu {
        position: static;
        width: auto;
        max-width: none;
        height: auto;
        background-color: transparent;
        border: none;
        padding: 0;
        flex-direction: row;
        align-items: center;
        gap: var(--space-6);
    }

    .nav__link {
        font-size: var(--text-sm);
        padding: var(--space-1) 0;
    }
}

/* Theme Toggle */
.theme-toggle {
    background: transparent;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-full);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--color-text);
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.theme-toggle__icon {
    display: none;
}

.theme-toggle__icon--light {
    display: block;
}

[data-theme="dark"] .theme-toggle__icon--light {
    display: none;
}

[data-theme="dark"] .theme-toggle__icon--dark {
    display: block;
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding-top: calc(var(--header-height) + var(--space-8));
    padding-bottom: var(--space-8);
    position: relative;
}

.hero__container {
    display: grid;
    gap: var(--space-10);
    align-items: center;
}

.hero__greeting {
    font-size: var(--text-lg);
    margin-bottom: var(--space-3);
    animation: blink-cursor 1s steps(1) infinite;
}

@keyframes blink-cursor {
    0%, 50% { opacity: 1; }
    51%, 100% { opacity: 0.7; }
}

.hero__title {
    font-size: var(--text-4xl);
    font-weight: 700;
    margin-bottom: var(--space-3);
    line-height: 1.1;
}

.hero__subtitle {
    font-family: var(--font-mono);
    font-size: var(--text-xl);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
}

.hero__tagline {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    max-width: 500px;
    margin-bottom: var(--space-8);
}

.hero__cta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
}

/* Hero Image */
.hero__image {
    display: flex;
    justify-content: center;
}

.hero__image-frame {
    position: relative;
    width: 250px;
    height: 250px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 3px solid var(--color-border);
    box-shadow: 0 10px 30px var(--color-shadow-lg);
    transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.hero__image-frame::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border: 3px solid var(--color-accent);
    border-radius: var(--radius-lg);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.hero__image-frame:hover::before {
    opacity: 1;
}

.hero__img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Placeholder for missing image */
.hero__img[src="assets/images/headshot.jpg"]:not([src*="data:"]) {
    background: var(--color-bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Hero Scroll Indicator */
.hero__scroll {
    position: absolute;
    bottom: var(--space-8);
    left: 50%;
    transform: translateX(-50%);
}

.hero__scroll-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-text-secondary);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    text-decoration: none;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-10px); }
    60% { transform: translateY(-5px); }
}

/* Desktop Hero Layout */
@media (min-width: 768px) {
    .hero__container {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-16);
    }

    .hero__title {
        font-size: var(--text-5xl);
    }

    .hero__image-frame {
        width: 300px;
        height: 300px;
    }
}

@media (min-width: 1024px) {
    .hero__image-frame {
        width: 350px;
        height: 350px;
    }
}

/* --------------------------------------------------------------------------
   Sections (General)
   -------------------------------------------------------------------------- */
.section {
    padding: var(--space-16) 0;
}

.section__title {
    font-size: var(--text-2xl);
    margin-bottom: var(--space-10);
    display: flex;
    align-items: center;
}

@media (min-width: 768px) {
    .section {
        padding: var(--space-20) 0;
    }

    .section__title {
        font-size: var(--text-3xl);
    }
}

/* --------------------------------------------------------------------------
   About Section
   -------------------------------------------------------------------------- */
.about__content {
    display: grid;
    gap: var(--space-10);
}

.about__bio {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
    line-height: 1.8;
}

.about__bio:last-child {
    margin-bottom: 0;
}

.about__interests {
    background-color: var(--color-bg-secondary);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    border-left: 4px solid var(--color-accent);
    transition: background-color var(--transition-base);
}

.about__interests-title {
    font-size: var(--text-lg);
    margin-bottom: var(--space-4);
    font-family: var(--font-mono);
}

.about__interests-list {
    list-style: none;
}

.about__interest-item {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    padding: var(--space-2) 0;
    border-bottom: 1px solid var(--color-border);
}

.about__interest-item:last-child {
    border-bottom: none;
}

.about__interest-item::before {
    content: '>';
    color: var(--color-accent);
    margin-right: var(--space-2);
}

@media (min-width: 768px) {
    .about__content {
        grid-template-columns: 2fr 1fr;
        gap: var(--space-12);
    }
}

/* --------------------------------------------------------------------------
   Clinical Focus Section
   -------------------------------------------------------------------------- */
.clinical__grid {
    display: grid;
    gap: var(--space-6);
}

.clinical__card {
    background-color: var(--color-bg-secondary);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: all var(--transition-fast);
}

.clinical__card:hover {
    border-color: var(--color-accent);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px var(--color-shadow);
}

.clinical__card-icon {
    color: var(--color-accent);
    margin-bottom: var(--space-4);
}

.clinical__card-title {
    font-size: var(--text-lg);
    margin-bottom: var(--space-2);
    font-family: var(--font-mono);
}

.clinical__card-desc {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

@media (min-width: 640px) {
    .clinical__grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .clinical__grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* --------------------------------------------------------------------------
   CV Section
   -------------------------------------------------------------------------- */
.cv__download {
    margin-bottom: var(--space-10);
}

.cv__sections {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.cv__section {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: border-color var(--transition-base);
}

.cv__section:hover {
    border-color: var(--color-accent);
}

.cv__section-header {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-5) var(--space-6);
    background-color: var(--color-bg-secondary);
    border: none;
    cursor: pointer;
    text-align: left;
    transition: background-color var(--transition-fast);
}

.cv__section-header:hover {
    background-color: var(--color-accent-light);
}

.cv__section-title {
    font-size: var(--text-base);
    font-family: var(--font-mono);
    font-weight: 600;
}

.cv__section-icon {
    font-family: var(--font-mono);
    font-size: var(--text-xl);
    color: var(--color-accent);
    font-weight: 400;
}

.cv__section-content {
    padding: var(--space-6);
    background-color: var(--color-bg);
    max-height: 1000px;
    overflow: hidden;
    transition: max-height var(--transition-slow), padding var(--transition-slow);
}

.cv__section-content--collapsed {
    max-height: 0;
    padding-top: 0;
    padding-bottom: 0;
}

.cv__item {
    padding: var(--space-4) 0;
    border-bottom: 1px solid var(--color-border);
}

.cv__item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.cv__item:first-child {
    padding-top: 0;
}

.cv__item-header {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: var(--space-2);
    margin-bottom: var(--space-1);
}

.cv__item-title {
    font-size: var(--text-base);
    font-family: var(--font-mono);
    font-weight: 500;
}

.cv__item-date {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    color: var(--color-accent);
}

.cv__item-org {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}

/* --------------------------------------------------------------------------
   Publications Section
   -------------------------------------------------------------------------- */
.publications__orcid {
    margin-bottom: var(--space-8);
}

.orcid-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    background-color: var(--color-bg-secondary);
    border-radius: var(--radius-full);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    color: var(--color-text);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.orcid-badge:hover {
    background-color: var(--color-accent-light);
    color: var(--color-text);
}

.orcid-badge__icon {
    width: 16px;
    height: 16px;
}

.publications__list {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    margin-bottom: var(--space-8);
}

.publications__loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-10);
    color: var(--color-text-secondary);
}

.publications__spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.publication-card {
    background-color: var(--color-bg-secondary);
    padding: var(--space-5);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: all var(--transition-fast);
}

.publication-card:hover {
    border-color: var(--color-accent);
    transform: translateX(4px);
}

.publication-card__title {
    font-size: var(--text-base);
    font-weight: 500;
    margin-bottom: var(--space-2);
    line-height: 1.4;
}

.publication-card__title a {
    color: var(--color-text);
    text-decoration: none;
}

.publication-card__title a:hover {
    color: var(--color-accent);
}

.publication-card__authors {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-2);
}

.publication-card__journal {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    color: var(--color-accent);
}

.publications__links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
}

/* --------------------------------------------------------------------------
   Links Section
   -------------------------------------------------------------------------- */
.links__grid {
    display: grid;
    gap: var(--space-4);
}

.link-card {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-5);
    background-color: var(--color-bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    text-decoration: none;
    color: var(--color-text);
    transition: all var(--transition-fast);
}

.link-card:hover {
    border-color: var(--color-accent);
    transform: translateX(4px);
    color: var(--color-text);
}

.link-card__icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-accent-light);
    border-radius: var(--radius-md);
    color: var(--color-accent);
}

.link-card__content {
    flex: 1;
}

.link-card__title {
    font-size: var(--text-base);
    font-family: var(--font-mono);
    font-weight: 600;
    margin-bottom: var(--space-1);
}

.link-card__desc {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}

.link-card__arrow {
    font-family: var(--font-mono);
    color: var(--color-accent);
    font-size: var(--text-lg);
    transition: transform var(--transition-fast);
}

.link-card:hover .link-card__arrow {
    transform: translateX(4px);
}

@media (min-width: 640px) {
    .links__grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* --------------------------------------------------------------------------
   Contact Section
   -------------------------------------------------------------------------- */
.contact__container {
    display: grid;
    gap: var(--space-10);
}

.contact__intro {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
    line-height: 1.7;
}

.contact__details {
    margin-bottom: var(--space-6);
}

.contact__detail {
    display: flex;
    gap: var(--space-3);
    padding: var(--space-3) 0;
    border-bottom: 1px solid var(--color-border);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
}

.contact__detail:last-child {
    border-bottom: none;
}

.contact__detail-label {
    color: var(--color-accent);
    min-width: 100px;
}

.contact__detail-value {
    color: var(--color-text-secondary);
}

/* Contact Form */
.contact__form {
    background-color: var(--color-bg-secondary);
    padding: var(--space-8);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.form__group {
    margin-bottom: var(--space-5);
}

.form__label {
    display: block;
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    margin-bottom: var(--space-2);
    color: var(--color-text);
}

.form__input,
.form__select,
.form__textarea {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    font-family: var(--font-sans);
    font-size: var(--text-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.form__input:focus,
.form__select:focus,
.form__textarea:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px var(--color-accent-light);
}

.form__select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%234a4a5e' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--space-4) center;
    padding-right: var(--space-10);
}

.form__textarea {
    resize: vertical;
    min-height: 120px;
}

.form__note {
    margin-top: var(--space-4);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    text-align: center;
}

@media (min-width: 768px) {
    .contact__container {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-12);
    }
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
    padding: var(--space-8) 0;
    border-top: 1px solid var(--color-border);
    background-color: var(--color-bg-secondary);
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.footer__container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
    text-align: center;
}

.footer__copyright,
.footer__updated {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}

.footer__links {
    display: flex;
    gap: var(--space-4);
}

.footer__links a {
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.footer__links a:hover {
    color: var(--color-accent);
}

@media (min-width: 768px) {
    .footer__container {
        flex-direction: row;
        justify-content: space-between;
    }

    .footer__content {
        display: flex;
        gap: var(--space-6);
    }
}

/* --------------------------------------------------------------------------
   Animations
   -------------------------------------------------------------------------- */
/* Fade in on scroll */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Overlay for mobile menu */
.nav-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
    z-index: 100;
}

.nav-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* --------------------------------------------------------------------------
   Utility Classes
   -------------------------------------------------------------------------- */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* --------------------------------------------------------------------------
   Additional States and Components
   -------------------------------------------------------------------------- */

/* Active Navigation Link */
.nav__link.active {
    color: var(--color-accent);
}

.nav__link.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--color-accent);
}

@media (min-width: 768px) {
    .nav__link {
        position: relative;
    }
}

/* Publication Error State */
.publications__error {
    text-align: center;
    padding: var(--space-8);
    color: var(--color-text-secondary);
}

.publications__error p {
    margin-bottom: var(--space-2);
}

.publications__error a {
    color: var(--color-accent);
    text-decoration: underline;
}

/* Contact Email Link */
.contact__email-link {
    color: var(--color-accent);
    text-decoration: none;
    font-family: var(--font-mono);
}

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

/* Image Placeholder (when headshot is missing) */
.hero__img[src="assets/images/headshot.jpg"] {
    background-color: var(--color-bg-secondary);
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 24 24' fill='none' stroke='%234a4a5e' stroke-width='1' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 21v-2a4 4 0 0 0-4-4H8a4 4 0 0 0-4 4v2'%3E%3C/path%3E%3Ccircle cx='12' cy='7' r='4'%3E%3C/circle%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: center;
    background-size: 40%;
}

/* Form Message States */
.form__message {
    padding: var(--space-4);
    margin-top: var(--space-4);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
    text-align: center;
}

.form__message--success {
    background-color: var(--color-accent-light);
    color: var(--color-accent);
    border: 1px solid var(--color-accent);
}

.form__message--error {
    background-color: rgba(220, 53, 69, 0.1);
    color: #dc3545;
    border: 1px solid #dc3545;
}

/* Disabled Button State */
.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Print Styles */
@media print {
    .header,
    .hero__scroll,
    .theme-toggle,
    .nav__toggle,
    .contact__form,
    .footer__links {
        display: none !important;
    }

    .hero {
        min-height: auto;
        padding-top: var(--space-8);
    }

    .section {
        page-break-inside: avoid;
    }

    body {
        font-size: 12pt;
        color: #000;
        background: #fff;
    }

    a {
        color: #000;
        text-decoration: underline;
    }
}