/* CSS Variables — research / quant terminal inspired */
:root {
    --bg-primary: #f6f4ef;
    --bg-secondary: #ebe8e0;
    --bg-tertiary: #e0dcd3;
    --text-primary: #12151c;
    --text-secondary: #4a5160;
    --text-muted: #7a8294;
    --accent: #0d9488;
    --accent-2: #7c3aed;
    --accent-hover: #0f766e;
    --border: #c9c4b8;
    --shadow: rgba(18, 21, 28, 0.08);
    --shadow-lg: rgba(18, 21, 28, 0.14);
    --grid-line: rgba(18, 21, 28, 0.06);
    --glow: rgba(13, 148, 136, 0.12);

    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    --space-3xl: 64px;
    --space-4xl: 96px;

    --font-sans: "Sora", system-ui, sans-serif;
    --font-serif: "Source Serif 4", Georgia, serif;
    --font-mono: "JetBrains Mono", ui-monospace, monospace;
    --font-family: var(--font-sans);

    --font-size-base: 16px;
    --font-size-sm: 14px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-2xl: 24px;
    --font-size-3xl: 32px;
    --font-size-4xl: clamp(2.25rem, 5vw, 3rem);

    --max-width: 1120px;
    --border-radius: 10px;
    --border-radius-sm: 6px;
    --transition: 0.2s ease;
}

[data-theme="dark"] {
    --bg-primary: #0c0e12;
    --bg-secondary: #12151c;
    --bg-tertiary: #1a1e28;
    --text-primary: #e8eaef;
    --text-secondary: #9aa3b2;
    --text-muted: #6b7280;
    --accent: #2dd4bf;
    --accent-2: #a78bfa;
    --accent-hover: #5eead4;
    --border: #2a3040;
    --shadow: rgba(0, 0, 0, 0.35);
    --shadow-lg: rgba(0, 0, 0, 0.55);
    --grid-line: rgba(232, 234, 239, 0.05);
    --glow: rgba(45, 212, 191, 0.08);
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .hero-kicker,
    .hero-equation,
    .hero-pills,
    .hero-tagline,
    .hero-cta,
    .hero-social {
        opacity: 1 !important;
        animation: none !important;
    }
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.65;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition), color var(--transition);
    letter-spacing: 0.01em;
}

.mono {
    font-family: var(--font-mono);
    letter-spacing: 0;
}

h1,
h2,
h3,
.section-title {
    font-family: var(--font-serif);
    letter-spacing: -0.02em;
}

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* Navigation */
.nav {
    position: sticky;
    top: 0;
    background-color: color-mix(in srgb, var(--bg-primary) 88%, transparent);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: background-color var(--transition), border-color var(--transition);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-md) var(--space-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-size: var(--font-size-lg);
    font-weight: 600;
    font-family: var(--font-mono);
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.nav-logo-mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    font-size: 1.1rem;
    line-height: 1;
    color: var(--accent);
    border: 1px solid var(--border);
    border-radius: var(--border-radius-sm);
    background: var(--bg-secondary);
}

.nav-logo:hover,
.nav-logo:focus {
    color: var(--accent);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--space-lg);
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link:focus {
    color: var(--accent);
    outline: none;
}

.nav-link.active {
    color: var(--accent);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-sm);
    z-index: 1001;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background-color: var(--text-primary);
    transition: var(--transition);
}

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

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

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

.theme-toggle {
    background: none;
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    padding: var(--space-sm);
    cursor: pointer;
    color: var(--text-primary);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover,
.theme-toggle:focus {
    background-color: var(--bg-secondary);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.theme-icon {
    transition: transform var(--transition);
}

.theme-toggle:hover .theme-icon {
    transform: rotate(15deg);
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 92vh;
    display: flex;
    align-items: center;
    padding: var(--space-4xl) 0;
    overflow: hidden;
    background: var(--bg-primary);
}

.hero-backdrop {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

.hero-grid {
    position: absolute;
    inset: -1px;
    background-image:
        linear-gradient(var(--grid-line) 1px, transparent 1px),
        linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
    background-size: 48px 48px;
    mask-image: radial-gradient(ellipse 70% 60% at 50% 35%, black 20%, transparent 70%);
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 50% at 50% -10%, var(--glow), transparent 55%),
        radial-gradient(ellipse 50% 40% at 100% 50%, color-mix(in srgb, var(--accent-2) 18%, transparent), transparent 60%),
        radial-gradient(ellipse 40% 35% at 0% 80%, color-mix(in srgb, var(--accent) 15%, transparent), transparent 55%);
}

.hero-clt-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: 2;
    opacity: 0.42;
    mix-blend-mode: multiply;
    mask-image: radial-gradient(
        ellipse 58% 52% at 50% 36%,
        transparent 0%,
        transparent 22%,
        rgba(0, 0, 0, 0.35) 42%,
        black 78%
    );
    -webkit-mask-image: radial-gradient(
        ellipse 58% 52% at 50% 36%,
        transparent 0%,
        transparent 22%,
        rgba(0, 0, 0, 0.35) 42%,
        black 78%
    );
}

[data-theme="dark"] .hero-clt-canvas {
    opacity: 0.38;
    mix-blend-mode: screen;
}

.hero .container {
    position: relative;
    z-index: 1;
}

.hero-content {
    text-align: center;
    max-width: 720px;
    margin: 0 auto;
}

.hero-kicker {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-bottom: var(--space-md);
    text-transform: uppercase;
    letter-spacing: 0.14em;
    opacity: 0;
    animation: fadeInUp 0.55s ease 0.05s forwards;
}

.hero-kicker .mono {
    color: var(--accent);
    letter-spacing: 0.08em;
}

.hero-title {
    font-size: var(--font-size-4xl);
    font-weight: 600;
    font-family: var(--font-serif);
    margin-bottom: var(--space-sm);
    opacity: 1;
    min-height: 1.2em;
    line-height: 1.15;
}

.hero-equation {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
    opacity: 0;
    animation: fadeInUp 0.55s ease 0.15s forwards;
}

.hero-equation sub {
    font-size: 0.7em;
    vertical-align: baseline;
}

.hero-pills {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    justify-content: center;
    margin-bottom: var(--space-xl);
    opacity: 0;
    animation: fadeInUp 0.6s ease 0.25s forwards;
}

.hero-pill {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 500;
    padding: var(--space-xs) var(--space-md);
    border-radius: 999px;
    border: 1px solid var(--border);
    background: color-mix(in srgb, var(--bg-secondary) 70%, transparent);
    color: var(--text-secondary);
}

.hero-tagline {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
    max-width: 34rem;
    margin-left: auto;
    margin-right: auto;
    opacity: 0;
    animation: fadeInUp 0.6s ease 0.35s forwards;
}

.hero-tagline strong {
    color: var(--text-primary);
    font-weight: 600;
}

.hero-intro {
    font-size: var(--font-size-lg);
    margin-bottom: var(--space-2xl);
    opacity: 0;
    animation: fadeInUp 0.6s ease 0.4s forwards;
}

.hero-cta {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-2xl);
    opacity: 0;
    animation: fadeInUp 0.6s ease 0.45s forwards;
}

.hero-social {
    display: flex;
    gap: var(--space-lg);
    justify-content: center;
    opacity: 0;
    animation: fadeInUp 0.6s ease 0.55s forwards;
}

.hero-social a {
    color: var(--text-secondary);
    transition: color var(--transition), transform var(--transition);
}

.hero-social a:hover,
.hero-social a:focus {
    color: var(--accent);
    transform: translateY(-2px);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: 4px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--space-md) var(--space-xl);
    font-size: var(--font-size-base);
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent) 0%, color-mix(in srgb, var(--accent) 75%, var(--accent-2)) 100%);
    color: #042f2e;
    box-shadow: 0 2px 14px color-mix(in srgb, var(--accent) 35%, transparent);
}

.btn-primary:hover,
.btn-primary:focus {
    filter: brightness(1.06);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px color-mix(in srgb, var(--accent) 45%, transparent);
    outline: 2px solid var(--accent-hover);
    outline-offset: 2px;
}

.btn-secondary {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover,
.btn-secondary:focus {
    background-color: var(--bg-tertiary);
    transform: translateY(-2px);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.btn-outline {
    background-color: transparent;
    color: var(--accent);
    border: 2px solid var(--accent);
}

.btn-outline:hover,
.btn-outline:focus {
    background-color: var(--accent);
    color: white;
    transform: translateY(-2px);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Sections */
.section {
    padding: var(--space-4xl) 0;
}

.section-alt {
    background-color: var(--bg-secondary);
    background-image:
        linear-gradient(var(--grid-line) 1px, transparent 1px),
        linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
    background-size: 40px 40px;
}

.section-title {
    font-size: var(--font-size-3xl);
    font-weight: 600;
    margin-bottom: var(--space-3xl);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
}

.section-index {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.12em;
}

/* About Section */
#about.section {
    position: relative;
    background-image: url('profile.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
}

#about.section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        135deg,
        color-mix(in srgb, var(--bg-primary) 92%, transparent) 0%,
        color-mix(in srgb, var(--bg-primary) 78%, transparent) 100%
    );
    z-index: 0;
}

[data-theme="dark"] #about.section::before {
    background: linear-gradient(
        135deg,
        color-mix(in srgb, var(--bg-primary) 94%, transparent) 0%,
        color-mix(in srgb, var(--bg-primary) 82%, transparent) 100%
    );
}

#about.section .container {
    position: relative;
    z-index: 1;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: start;
}

.about-content p {
    text-indent: var(--space-lg);
    margin-bottom: var(--space-md);
}

.about-content p:last-of-type {
    margin-bottom: 0;
}

.about-content h3 {
    font-size: var(--font-size-xl);
    margin-top: var(--space-xl);
    margin-bottom: var(--space-md);
}

.about-list {
    list-style: none;
    padding-left: 0;
}

.about-list li {
    padding: var(--space-sm) 0;
    padding-left: var(--space-lg);
    position: relative;
}

.about-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent);
}

.about-education {
    background-color: var(--bg-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    box-shadow: 0 2px 8px var(--shadow);
}

.about-education h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--space-lg);
    color: var(--accent);
}

.education-item {
    margin-bottom: var(--space-lg);
}

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

.education-degree {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.education-minor {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: var(--space-md);
}

.education-school {
    font-size: var(--font-size-base);
    color: var(--accent);
    font-weight: 600;
    margin-bottom: var(--space-xs);
}

.education-date {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--space-sm);
}

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

/* Skills Section */
.skills-container {
    max-width: 1000px;
    margin: 0 auto;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-3xl);
}

.strengths-section {
    background-color: var(--bg-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    box-shadow: 0 2px 8px var(--shadow);
    max-width: 800px;
    margin: 0 auto;
}

.strengths-title {
    font-size: var(--font-size-xl);
    margin-bottom: var(--space-lg);
    color: var(--accent);
    text-align: center;
}

.strengths-list {
    list-style: none;
    padding-left: 0;
    display: grid;
    gap: var(--space-md);
}

.strengths-list li {
    padding: var(--space-md);
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    border-left: 3px solid var(--accent);
    transition: transform var(--transition), box-shadow var(--transition);
}

.strengths-list li:hover {
    transform: translateX(4px);
    box-shadow: 0 2px 8px var(--shadow);
}

.strengths-list li strong {
    color: var(--accent);
    display: block;
    margin-bottom: var(--space-xs);
}

.skill-group {
    background-color: var(--bg-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    box-shadow: 0 2px 8px var(--shadow);
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.skill-group:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 28px var(--shadow-lg);
    border-color: color-mix(in srgb, var(--accent) 35%, var(--border));
}

.skill-group-title {
    font-size: var(--font-size-lg);
    font-family: var(--font-mono);
    font-weight: 600;
    margin-bottom: var(--space-lg);
    color: var(--accent);
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
}

.skill-tag {
    padding: var(--space-sm) var(--space-md);
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--border-radius-sm);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-primary);
    transition: var(--transition);
}

.skill-tag:hover {
    background-color: color-mix(in srgb, var(--accent) 18%, var(--bg-secondary));
    color: var(--text-primary);
    border-color: var(--accent);
    transform: translateY(-2px);
}

/* Discrete lattice random walks (projects + coursework) */
.section-random-walk {
    position: relative;
    overflow: hidden;
}

.random-walk-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
    opacity: 0.97;
    mix-blend-mode: normal;
}

[data-theme="dark"] .random-walk-canvas {
    opacity: 0.94;
}

.section-random-walk .container {
    position: relative;
    z-index: 1;
}

.section-random-walk .section-title,
.section-random-walk#projects .projects-footer p {
    text-shadow:
        0 0 1.25rem color-mix(in srgb, var(--bg-primary) 92%, transparent),
        0 0 0.35rem color-mix(in srgb, var(--bg-primary) 70%, transparent);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: var(--space-xl);
}

.project-card {
    background-color: color-mix(in srgb, var(--bg-primary) 68%, transparent);
    backdrop-filter: saturate(1.15) blur(14px);
    -webkit-backdrop-filter: saturate(1.15) blur(14px);
    padding: var(--space-xl);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 8px var(--shadow);
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    opacity: 0.85;
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 36px var(--shadow-lg);
    border-color: color-mix(in srgb, var(--accent) 28%, var(--border));
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    .project-card {
        background-color: color-mix(in srgb, var(--bg-primary) 93%, transparent);
    }
}

.project-title {
    font-size: var(--font-size-xl);
    margin-bottom: var(--space-md);
    margin-top: var(--space-sm);
    color: var(--text-primary);
}

.project-title::after {
    content: '';
    display: block;
    width: 2.5rem;
    height: 2px;
    margin-top: var(--space-sm);
    background: linear-gradient(90deg, var(--accent), transparent);
}

.project-description {
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
}

.project-highlights {
    list-style: none;
    margin-bottom: var(--space-lg);
    padding-left: 0;
}

.project-highlights li {
    padding: var(--space-xs) 0;
    padding-left: var(--space-lg);
    position: relative;
    color: var(--text-secondary);
}

.project-highlights li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: bold;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.project-tag {
    padding: var(--space-xs) var(--space-md);
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-secondary);
}

.project-links {
    display: flex;
    gap: var(--space-md);
    margin-top: var(--space-md);
}

.project-link {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.project-link:hover,
.project-link:focus {
    text-decoration: underline;
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.projects-footer {
    text-align: center;
    margin-top: var(--space-3xl);
    padding-top: var(--space-xl);
}

.projects-footer p {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
}

.github-link {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.github-link:hover,
.github-link:focus {
    text-decoration: underline;
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Experience Section */
.experience-list {
    max-width: 800px;
    margin: 0 auto;
}

.experience-item {
    margin-bottom: var(--space-3xl);
    padding-bottom: var(--space-3xl);
    border-bottom: 1px solid var(--border);
}

.experience-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: var(--space-sm);
    flex-wrap: wrap;
    gap: var(--space-md);
}

.experience-title {
    font-size: var(--font-size-xl);
    font-family: var(--font-serif);
    margin-bottom: var(--space-xs);
}

.experience-date {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    white-space: nowrap;
}

.experience-org {
    color: var(--accent);
    font-weight: 600;
    margin-bottom: var(--space-md);
}

.experience-details {
    list-style: none;
    padding-left: 0;
}

.experience-details li {
    padding: var(--space-xs) 0;
    padding-left: var(--space-lg);
    position: relative;
    color: var(--text-secondary);
}

.experience-details li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* Coursework Section */
.coursework-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-xl);
}

.coursework-group {
    background-color: var(--bg-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    box-shadow: 0 2px 8px var(--shadow);
}

.section-random-walk#coursework .coursework-group {
    background-color: color-mix(in srgb, var(--bg-primary) 68%, transparent);
    backdrop-filter: saturate(1.15) blur(14px);
    -webkit-backdrop-filter: saturate(1.15) blur(14px);
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    .section-random-walk#coursework .coursework-group {
        background-color: color-mix(in srgb, var(--bg-primary) 93%, transparent);
    }
}

.coursework-group-title {
    font-size: var(--font-size-lg);
    font-family: var(--font-mono);
    font-weight: 600;
    margin-bottom: var(--space-lg);
    color: var(--accent);
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.coursework-list {
    list-style: none;
    padding-left: 0;
}

.coursework-list li {
    padding: var(--space-sm) 0;
    padding-left: var(--space-lg);
    position: relative;
    color: var(--text-secondary);
}

.coursework-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* Highlights Section */
.highlights-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-xl);
    text-align: center;
}

.highlight-item {
    padding: var(--space-xl);
}

.highlight-number {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--accent);
    margin-bottom: var(--space-sm);
}

.highlight-label {
    color: var(--text-secondary);
    font-size: var(--font-size-lg);
}

/* Contact Section */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    max-width: 900px;
    margin: 0 auto;
}

.contact-info {
    color: var(--text-secondary);
}

.contact-details {
    margin-top: var(--space-xl);
}

.contact-detail {
    margin-bottom: var(--space-md);
}

.contact-detail a {
    color: var(--accent);
    text-decoration: none;
}

.contact-detail a:hover,
.contact-detail a:focus {
    text-decoration: underline;
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Form Styles */
.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: var(--space-sm);
    font-weight: 600;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea {
    padding: var(--space-md);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    font-family: inherit;
    font-size: var(--font-size-base);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-color: var(--accent);
}

.form-group input:invalid:not(:focus):not(:placeholder-shown),
.form-group textarea:invalid:not(:focus):not(:placeholder-shown) {
    border-color: #dc3545;
}

.error-message {
    color: #dc3545;
    font-size: var(--font-size-sm);
    margin-top: var(--space-xs);
    min-height: 20px;
}

.toast {
    position: fixed;
    bottom: var(--space-xl);
    right: var(--space-xl);
    padding: var(--space-md) var(--space-xl);
    background-color: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    box-shadow: 0 4px 12px var(--shadow-lg);
    color: var(--text-primary);
    font-weight: 600;
    opacity: 0;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 2000;
    max-width: 300px;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

.toast.success {
    border-color: #28a745;
    background-color: #d4edda;
    color: #155724;
}

[data-theme="dark"] .toast.success {
    background-color: #1e4620;
    color: #90ee90;
    border-color: #28a745;
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    padding: var(--space-xl) 0;
    text-align: center;
    color: var(--text-secondary);
    border-top: 1px solid var(--border);
}

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

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        background-color: var(--bg-primary);
        flex-direction: column;
        padding: var(--space-4xl) var(--space-xl);
        box-shadow: -2px 0 8px var(--shadow);
        transition: right var(--transition);
        align-items: flex-start;
        gap: var(--space-lg);
    }

    .nav-menu.active {
        right: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-title {
        font-size: var(--font-size-3xl);
    }

    .hero-tagline {
        font-size: var(--font-size-lg);
    }

    #about.section {
        background-attachment: scroll;
    }

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

    .strengths-list li {
        padding: var(--space-sm) var(--space-md);
    }

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

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

    .experience-header {
        flex-direction: column;
    }

    .section-title {
        font-size: var(--font-size-2xl);
    }

    .toast {
        right: var(--space-md);
        left: var(--space-md);
        max-width: none;
    }
}

@media (max-width: 480px) {
    .hero {
        min-height: auto;
        padding: var(--space-3xl) 0;
    }

    .hero-title {
        font-size: var(--font-size-2xl);
    }

    .hero-cta {
        flex-direction: column;
    }

    .hero-cta .btn {
        width: 100%;
        text-align: center;
    }

    .container {
        padding: 0 var(--space-md);
    }

    .section {
        padding: var(--space-3xl) 0;
    }
}