/* CSS Variables - Neutral warm palette */
:root {
    --color-bg: #fafafa;
    --color-bg-warm: #f5f3f0;
    --color-surface: #ffffff;
    --color-surface-alt: #f8f7f5;
    --color-text: #1a1a1a;
    --color-text-muted: #5c5c5c;
    --color-text-light: #787878;
    --color-primary: #2c2c2c;
    --color-primary-hover: #000000;
    --color-accent: #8b7355;
    --color-accent-light: #a89070;
    --color-border: #e5e3e0;
    --color-border-dark: #d0cdc8;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji';
    --font-mono: 'SF Mono', SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    --max-width: 900px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08), 0 2px 4px rgba(0,0,0,0.06);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
    --radius: 12px;
    --radius-sm: 8px;
    --safe-area-top: env(safe-area-inset-top, 0px);
    --safe-area-bottom: env(safe-area-inset-bottom, 0px);
    --safe-area-left: env(safe-area-inset-left, 0px);
    --safe-area-right: env(safe-area-inset-right, 0px);
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-text-size-adjust: 100%;
    -moz-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

html {
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text);
    background-color: var(--color-bg);
    overflow-x: hidden;
    padding-left: var(--safe-area-left);
    padding-right: var(--safe-area-right);
    font-weight: 400;
    overscroll-behavior-y: none;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    padding-left: max(var(--spacing-md), var(--safe-area-left));
    padding-right: max(var(--spacing-md), var(--safe-area-right));
}

/* Typography */
h1, h2, h3 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-text);
    text-wrap: balance;
    -webkit-hyphens: auto;
    -ms-hyphens: auto;
    hyphens: auto;
}

h1 {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    letter-spacing: -0.03em;
}

h2 {
    font-size: clamp(1.25rem, 3vw, 1.5rem);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--color-border);
}

h3 {
    font-size: clamp(1.1rem, 2.5vw, 1.25rem);
    margin-bottom: var(--spacing-xs);
}

p {
    margin-bottom: var(--spacing-sm);
}

/* Bio styling */
.bio p {
    font-size: clamp(0.9375rem, 2vw, 1.0625rem);
    color: var(--color-text-muted);
    max-width: 65ch;
}

.bio strong {
    color: var(--color-text);
    font-weight: 600;
}

.bio p:last-child {
    margin-bottom: 0;
}

/* Links */
a {
    color: var(--color-accent);
    text-decoration: none;
    -webkit-transition: color 0.3s ease;
    -moz-transition: color 0.3s ease;
    -o-transition: color 0.3s ease;
    transition: color 0.3s ease;
    -webkit-tap-highlight-color: transparent;
}

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

/* Animations */
@-webkit-keyframes fadeInUp {
    from {
        opacity: 0;
        -webkit-transform: translateY(20px);
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        -webkit-transform: translateY(0);
        transform: translateY(0);
    }
}
@keyframes fadeInUp {
    from {
        opacity: 0;
        -webkit-transform: translateY(20px);
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        -webkit-transform: translateY(0);
        transform: translateY(0);
    }
}

@-webkit-keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Header / Hero with gradient */
.hero {
    background: linear-gradient(135deg, #ffffff 0%, #f5f3f0 50%, #ebe8e4 100%);
    padding: var(--spacing-xl) 0 var(--spacing-lg);
    padding-top: calc(var(--spacing-xl) + var(--safe-area-top));
    text-align: center;
    border-bottom: 1px solid var(--color-border);
    position: relative;
}

.headshot {
    width: clamp(120px, 25vw, 180px);
    height: clamp(120px, 25vw, 180px);
    border-radius: 50%;
    -o-object-fit: cover;
    object-fit: cover;
    margin-bottom: var(--spacing-md);
    -webkit-box-shadow: var(--shadow-lg);
    box-shadow: var(--shadow-lg);
    border: 4px solid var(--color-surface);
    -webkit-animation: fadeIn 0.8s ease-out;
    animation: fadeIn 0.8s ease-out;
    -webkit-transition: -webkit-transform 0.3s ease, -webkit-box-shadow 0.3s ease;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    -webkit-user-drag: none;
    user-select: none;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.headshot:hover {
    -webkit-transform: scale(1.02);
    -ms-transform: scale(1.02);
    transform: scale(1.02);
}

.hero h1 {
    -webkit-animation: fadeInUp 0.6s ease-out 0.2s both;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.tagline {
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-sm);
    font-weight: 400;
    letter-spacing: 0.02em;
    -webkit-animation: fadeInUp 0.6s ease-out 0.3s both;
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.hero-quote {
    font-size: clamp(0.9rem, 2vw, 1rem);
    color: var(--color-accent);
    font-style: italic;
    margin-bottom: var(--spacing-md);
    -webkit-animation: fadeInUp 0.6s ease-out 0.35s both;
    animation: fadeInUp 0.6s ease-out 0.35s both;
}

/* Profile Links */
.profile-links {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
    gap: var(--spacing-sm);
    -webkit-flex-wrap: wrap;
    -ms-flex-wrap: wrap;
    flex-wrap: wrap;
    -webkit-animation: fadeInUp 0.6s ease-out 0.4s both;
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.profile-links a {
    display: -webkit-inline-box;
    display: -webkit-inline-flex;
    display: -ms-inline-flexbox;
    display: inline-flex;
    -webkit-box-align: center;
    -webkit-align-items: center;
    -ms-flex-align: center;
    align-items: center;
    gap: 0.5rem;
    min-height: 44px;
    padding: 0.6rem 1.2rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    color: var(--color-text);
    font-size: 0.875rem;
    font-weight: 500;
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.profile-links a:hover,
.profile-links a:focus {
    border-color: var(--color-border-dark);
    background: var(--color-surface-alt);
    -webkit-box-shadow: var(--shadow-sm);
    box-shadow: var(--shadow-sm);
    -webkit-transform: translateY(-2px);
    -ms-transform: translateY(-2px);
    transform: translateY(-2px);
}

.profile-links a:active {
    -webkit-transform: translateY(0);
    -ms-transform: translateY(0);
    transform: translateY(0);
    -webkit-transition-duration: 0.1s;
    transition-duration: 0.1s;
}

.profile-links svg {
    width: 18px;
    height: 18px;
    -webkit-flex-shrink: 0;
    -ms-flex-negative: 0;
    flex-shrink: 0;
}

/* Main Content Sections */
main section {
    padding: var(--spacing-lg) 0;
    -webkit-animation: fadeIn 0.6s ease-out;
    animation: fadeIn 0.6s ease-out;
}

/* Alternating section backgrounds with gradients */
.about {
    background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-surface) 100%);
}

.contact {
    background: var(--color-surface);
}

.publications {
    background: linear-gradient(180deg, var(--color-bg-warm) 0%, var(--color-bg) 100%);
}

.patents {
    background: linear-gradient(180deg, var(--color-surface) 0%, var(--color-bg-warm) 100%);
}

/* Contact/Inquiries Section */
.inquiries {
    background: var(--color-surface);
    text-align: center;
}

.inquiries p {
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
}

.btn-contact {
    gap: 0.5rem;
    font-size: 1rem;
    padding: 0.75rem 1.5rem;
}

.btn-contact svg {
    flex-shrink: 0;
}

/* About Section */
.about p {
    font-size: clamp(0.9375rem, 2vw, 1.0625rem);
    color: var(--color-text-muted);
    max-width: 65ch;
    -webkit-animation: fadeInUp 0.6s ease-out 0.2s both;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

/* Platform Grid (Find My Work) */
.contact p {
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
}

.platform-grid {
    display: -ms-grid;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-sm);
}

.platform-card {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-orient: vertical;
    -webkit-box-direction: normal;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;
    min-height: 72px;
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    color: var(--color-text);
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    -webkit-tap-highlight-color: transparent;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.platform-card:hover,
.platform-card:focus {
    border-color: var(--color-border-dark);
    -webkit-box-shadow: var(--shadow-md);
    box-shadow: var(--shadow-md);
    -webkit-transform: translateY(-2px);
    -ms-transform: translateY(-2px);
    transform: translateY(-2px);
}

.platform-card:active {
    -webkit-transform: translateY(0);
    -ms-transform: translateY(0);
    transform: translateY(0);
}

.platform-card strong {
    font-size: 1rem;
    margin-bottom: 0.25rem;
    color: var(--color-text);
}

.platform-card span {
    font-size: 0.8125rem;
    color: var(--color-text-light);
}

/* Publications Section */
.paper {
    background: var(--color-surface);
    padding: var(--spacing-md);
    border-radius: var(--radius);
    margin-bottom: var(--spacing-md);
    -webkit-box-shadow: var(--shadow-sm);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.paper:hover {
    -webkit-box-shadow: var(--shadow-md);
    box-shadow: var(--shadow-md);
    -webkit-transform: translateY(-3px);
    -ms-transform: translateY(-3px);
    transform: translateY(-3px);
}

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

.paper-meta {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
}

.paper-description {
    color: var(--color-text-muted);
    font-size: clamp(0.875rem, 2vw, 0.9375rem);
    margin-bottom: var(--spacing-sm);
}

.paper-links {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-flex-wrap: wrap;
    -ms-flex-wrap: wrap;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: var(--spacing-sm);
}

/* PDF Preview */
.pdf-preview {
    margin-top: var(--spacing-md);
    border-radius: var(--radius-sm);
    overflow: hidden;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
}

.pdf-preview:hover {
    border-color: var(--color-border-dark);
}

.pdf-embed-container {
    position: relative;
    width: 100%;
}

.pdf-preview iframe {
    width: 100%;
    height: 400px;
    border: none;
    display: block;
    background: var(--color-bg);
}

.pdf-preview-label {
    display: block;
    padding: 0.75rem var(--spacing-sm);
    background: var(--color-surface-alt);
    color: var(--color-text-light);
    font-size: 0.8125rem;
    border-bottom: 1px solid var(--color-border);
}

.pdf-mobile-fallback {
    display: none;
    width: 100%;
    margin-top: var(--spacing-sm);
    text-align: center;
    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
}

/* Patents Section */
.patent-item {
    background: var(--color-surface);
    padding: var(--spacing-md);
    border-radius: var(--radius);
    margin-bottom: var(--spacing-sm);
    border: 1px solid var(--color-border);
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.patent-item:hover {
    border-color: var(--color-border-dark);
    -webkit-box-shadow: var(--shadow-sm);
    box-shadow: var(--shadow-sm);
    -webkit-transform: translateX(4px);
    -ms-transform: translateX(4px);
    transform: translateX(4px);
}

.patent-item:last-child {
    margin-bottom: 0;
}

.patent-number {
    font-family: var(--font-mono);
    font-size: clamp(0.75rem, 2vw, 0.8125rem);
    color: var(--color-accent);
    margin-bottom: 0.5rem;
    display: block;
    white-space: nowrap;
    overflow: hidden;
    -o-text-overflow: ellipsis;
    text-overflow: ellipsis;
}

.patent-title {
    font-size: clamp(0.9rem, 2vw, 1rem);
    color: var(--color-text);
    font-weight: 500;
    line-height: 1.5;
}

/* Buttons */
.btn {
    display: -webkit-inline-box;
    display: -webkit-inline-flex;
    display: -ms-inline-flexbox;
    display: inline-flex;
    -webkit-box-align: center;
    -webkit-align-items: center;
    -ms-flex-align: center;
    align-items: center;
    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
    min-height: 44px;
    padding: 0.6rem 1.2rem;
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    color: var(--color-text);
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.btn:hover,
.btn:focus {
    border-color: var(--color-border-dark);
    background: var(--color-surface-alt);
    -webkit-transform: translateY(-1px);
    -ms-transform: translateY(-1px);
    transform: translateY(-1px);
}

.btn:active {
    -webkit-transform: translateY(0);
    -ms-transform: translateY(0);
    transform: translateY(0);
    -webkit-transition-duration: 0.1s;
    transition-duration: 0.1s;
}

.btn-primary {
    background: linear-gradient(135deg, #3a3a3a 0%, #1a1a1a 100%);
    border-color: #1a1a1a;
    color: white;
}

.btn-primary:hover,
.btn-primary:focus {
    background: linear-gradient(135deg, #4a4a4a 0%, #2a2a2a 100%);
    border-color: #000000;
    color: white;
    -webkit-box-shadow: var(--shadow-sm);
    box-shadow: var(--shadow-sm);
}

/* Footer */
footer {
    background: linear-gradient(180deg, var(--color-bg-warm) 0%, #e8e5e0 100%);
    color: var(--color-text-muted);
    padding: var(--spacing-md) 0;
    padding-bottom: calc(var(--spacing-md) + var(--safe-area-bottom));
    text-align: center;
    font-size: 0.875rem;
    border-top: 1px solid var(--color-border);
}

footer p {
    margin-bottom: var(--spacing-xs);
}

footer p:last-child {
    margin-bottom: 0;
}

footer a {
    color: var(--color-text);
    text-decoration: underline;
    -webkit-text-decoration-skip: ink;
    text-decoration-skip-ink: auto;
    text-underline-offset: 2px;
    -webkit-transition: color 0.3s ease;
    -moz-transition: color 0.3s ease;
    -o-transition: color 0.3s ease;
    transition: color 0.3s ease;
}

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

.attribution {
    font-size: 0.8125rem;
    color: var(--color-text-light);
}

/* ==================== */
/* RESPONSIVE - TABLET  */
/* ==================== */
@media (max-width: 768px) {
    :root {
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
    }

    .container {
        padding-left: max(var(--spacing-sm), var(--safe-area-left));
        padding-right: max(var(--spacing-sm), var(--safe-area-right));
    }

    .pdf-preview iframe {
        height: 350px;
    }

    .platform-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ==================== */
/* RESPONSIVE - MOBILE  */
/* ==================== */
@media (max-width: 640px) {
    :root {
        --spacing-lg: 2.5rem;
        --spacing-xl: 3rem;
        --spacing-md: 1.5rem;
    }

    .profile-links {
        gap: 0.5rem;
    }

    .profile-links a {
        padding: 0.5rem 0.875rem;
        font-size: 0.8125rem;
    }

    .paper-links {
        -webkit-box-orient: vertical;
        -webkit-box-direction: normal;
        -webkit-flex-direction: column;
        -ms-flex-direction: column;
        flex-direction: column;
    }

    .paper-links .btn {
        width: 100%;
        text-align: center;
    }

    .platform-grid {
        grid-template-columns: 1fr;
    }

    .pdf-embed-container {
        display: none;
    }

    .pdf-mobile-fallback {
        display: -webkit-inline-flex;
        display: -ms-inline-flexbox;
        display: inline-flex;
    }

    .patent-item {
        padding: var(--spacing-sm);
    }

    .patent-item:hover {
        -webkit-transform: none;
        -ms-transform: none;
        transform: none;
    }

    .paper:hover {
        -webkit-transform: none;
        -ms-transform: none;
        transform: none;
    }
}

/* ==================== */
/* RESPONSIVE - SMALL   */
/* ==================== */
@media (max-width: 380px) {
    :root {
        --spacing-sm: 0.75rem;
    }

    .profile-links a {
        padding: 0.5rem 0.75rem;
        font-size: 0.75rem;
    }

    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.8125rem;
    }
}

/* ==================== */
/* PRINT STYLES         */
/* ==================== */
@media print {
    * {
        -webkit-print-color-adjust: exact !important;
        print-color-adjust: exact !important;
    }

    body {
        background: white;
        color: black;
    }

    .hero {
        padding: var(--spacing-md) 0;
        background: white;
    }

    .profile-links,
    .paper-links,
    .platform-grid,
    .pdf-preview {
        display: none;
    }

    footer {
        background: white;
        border-top: 1px solid #ccc;
    }

    a {
        color: black;
        text-decoration: underline;
    }

    a[href^="http"]::after {
        content: " (" attr(href) ")";
        font-size: 0.8em;
        color: #666;
    }
}

/* ==================== */
/* ACCESSIBILITY        */
/* ==================== */
a:focus-visible,
.btn:focus-visible,
.platform-card:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

@media (prefers-contrast: high) {
    :root {
        --color-border: #999999;
        --color-text-muted: #444444;
    }
}

/* ==================== */
/* REDUCED MOTION       */
/* ==================== */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *, *::before, *::after {
        -webkit-animation: none !important;
        animation: none !important;
        -webkit-transition: none !important;
        -moz-transition: none !important;
        -o-transition: none !important;
        transition: none !important;
    }
}

/* ==================== */
/* FIREFOX SCROLLBAR    */
/* ==================== */
@-moz-document url-prefix() {
    html {
        scrollbar-width: thin;
        scrollbar-color: var(--color-border-dark) var(--color-bg);
    }
}

/* ==================== */
/* WEBKIT SCROLLBAR     */
/* ==================== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border-dark);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-light);
}

/* ==================== */
/* SELECTION STYLING    */
/* ==================== */
::-moz-selection {
    background: var(--color-accent);
    color: white;
}

::selection {
    background: var(--color-accent);
    color: white;
}