/* ============================================================
 * portfolio.css — Portfolio Landing Page
 * ============================================================
 * Eigenständiges Stylesheet für die neue Landingpage.
 * Zwei Modes: Mensch (warm/hell) und Coder (dunkel/terminal).
 * Fonts: JetBrains Mono (Headlines/Code) + IBM Plex Sans (Body)
 * ============================================================ */

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

/* ---- Design Tokens: Mensch Mode (Default) ---- */
:root {
    --bg:             #f5f0e8;
    --bg-surface:     #ede6d8;
    --bg-card:        #faf7f2;
    --border:         #d4cbb8;
    --border-light:   #e8e0d0;
    --text:           #2c2416;
    --text-secondary: #6b5d4d;
    --text-muted:     #9b8e7e;
    --accent:         #e85d26;
    --accent-hover:   #d04d1a;
    --accent-soft:    rgba(232, 93, 38, 0.1);
    --accent-glow:    rgba(232, 93, 38, 0.15);
    --code:           #4a7c59;
    --grain-opacity:  0.02;

    --shadow-sm:  0 1px 3px rgba(44, 36, 22, 0.06);
    --shadow-md:  0 4px 16px rgba(44, 36, 22, 0.08);
    --shadow-lg:  0 8px 24px rgba(44, 36, 22, 0.1);

    --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-display: 'JetBrains Mono', monospace;
    --font-body:    'IBM Plex Sans', sans-serif;
    --font-mono:    'JetBrains Mono', monospace;

    --max-width:   1100px;
    --nav-height:  60px;
    --radius:      8px;
    --radius-sm:   4px;
    --transition:  0.3s ease;
    --transition-fast: 0.15s ease;
}

/* ---- Design Tokens: Coder Mode ---- */
[data-mode="coder"] {
    --bg:             #111111;
    --bg-surface:     #1a1a1a;
    --bg-card:        #1a1a1a;
    --border:         #2a2a2a;
    --border-light:   #222222;
    --text:           #f0f0f0;
    --text-secondary: #888888;
    --text-muted:     #555555;
    --accent:         #e85d26;
    --accent-hover:   #f06a33;
    --accent-soft:    rgba(232, 93, 38, 0.12);
    --accent-glow:    rgba(232, 93, 38, 0.2);
    --code:           #a3c4a3;
    --grain-opacity:  0.03;

    --shadow-sm:  0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md:  0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg:  0 8px 24px rgba(0, 0, 0, 0.5);
}

/* ---- Base ---- */
body {
    font-family: var(--font-body);
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    transition: background var(--transition), color var(--transition);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Subtle grain texture */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    opacity: var(--grain-opacity);
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---- Typography ---- */
h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.3;
    color: var(--text);
    transition: color var(--transition);
}

h1 { font-size: clamp(2.2rem, 5vw, 3.4rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2rem); }
h3 { font-size: 1.15rem; }

p {
    color: var(--text-secondary);
    transition: color var(--transition);
}

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

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

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

/* ---- Layout ---- */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-lg);
    position: relative;
    z-index: 1;
}

section {
    padding: var(--space-4xl) 0;
}

.bg-alt {
    background: var(--bg-surface);
    transition: background var(--transition);
}

/* ---- Navigation ---- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 900;
    background: var(--bg);
    border-bottom: 1px solid var(--border-light);
    padding: 0 var(--space-lg);
    transition: all var(--transition);
    opacity: 0.97;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

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

.nav-brand {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 16px;
    color: var(--text);
    text-decoration: none;
    letter-spacing: -0.02em;
    transition: color var(--transition);
}

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

.nav-links {
    display: flex;
    gap: 28px;
    list-style: none;
}

.nav-links a {
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 400;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    letter-spacing: 0.01em;
}

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

.nav-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-sm);
    color: var(--text);
}

.nav-menu-btn svg {
    width: 22px;
    height: 22px;
    stroke: currentColor;
    fill: none;
    stroke-width: 2;
    stroke-linecap: round;
}

/* ---- Mode Toggle ---- */
.mode-toggle-wrap {
    position: fixed;
    top: 16px;
    right: 16px;
    z-index: 1000;
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 32px;
    padding: 5px 14px 5px 5px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition);
}

.mode-toggle-wrap:hover {
    box-shadow: var(--shadow-md);
}

.mode-toggle {
    position: relative;
    width: 44px;
    height: 24px;
    background: var(--border);
    border-radius: 12px;
    cursor: pointer;
    transition: background var(--transition);
    border: none;
    outline: none;
    -webkit-appearance: none;
}

.mode-toggle::after {
    content: '';
    position: absolute;
    top: 3px;
    left: 3px;
    width: 18px;
    height: 18px;
    background: var(--bg-card);
    border-radius: 50%;
    transition: transform var(--transition), background var(--transition);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

[data-mode="coder"] .mode-toggle {
    background: var(--accent);
}

[data-mode="coder"] .mode-toggle::after {
    transform: translateX(20px);
    background: var(--bg);
}

.mode-label {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    color: var(--text-muted);
    user-select: none;
    letter-spacing: 0.03em;
    transition: color var(--transition);
}

/* ---- Hero ---- */
.hero {
    min-height: 92vh;
    display: flex;
    align-items: center;
    padding-top: calc(var(--nav-height) + 40px);
}

.hero-content {
    max-width: 720px;
}

.hero-terminal {
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--code);
    margin-bottom: var(--space-xl);
    display: flex;
    align-items: center;
    gap: 8px;
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.2s;
}

.terminal-prompt {
    color: var(--text-muted);
}

.terminal-cursor {
    display: inline-block;
    width: 8px;
    color: var(--code);
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0; }
}

.hero-role {
    font-family: var(--font-mono);
    font-size: clamp(13px, 1.5vw, 15px);
    color: var(--accent);
    letter-spacing: 0.04em;
    margin-bottom: var(--space-lg);
    line-height: 1.6;
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.4s;
}

.hero h1 {
    margin-bottom: var(--space-lg);
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.5s;
}

.hero-tagline {
    font-size: clamp(17px, 2vw, 20px);
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
    line-height: 1.6;
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.6s;
}

.hero-links {
    display: flex;
    gap: var(--space-md);
    flex-wrap: wrap;
    margin-bottom: var(--space-xl);
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.7s;
}

.hero-link {
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    padding: 8px 18px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.hero-link:hover {
    color: var(--accent);
    border-color: var(--accent);
    background: var(--accent-soft);
}

.hero-link--accent {
    color: var(--accent);
    border-color: var(--accent);
}

.hero-link--accent:hover {
    background: var(--accent);
    color: #fff;
}

.hero-sub {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--text-muted);
    letter-spacing: 0.02em;
    opacity: 0;
    animation: fadeUp 0.6s ease forwards 0.8s;
}

/* ---- Section Header ---- */
.section-label {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--accent);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.section-title {
    margin-bottom: var(--space-md);
}

.section-desc {
    font-size: 16px;
    color: var(--text-secondary);
    max-width: 640px;
    line-height: 1.7;
}

.section-header {
    margin-bottom: var(--space-2xl);
}

/* ---- Featured Project ---- */
.featured {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: var(--space-2xl);
    background: var(--bg-card);
    transition: all var(--transition);
}

.featured:hover {
    border-color: var(--accent);
    box-shadow: 0 0 0 1px var(--accent), var(--shadow-lg);
}

.featured-label {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--accent);
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-bottom: var(--space-md);
}

.featured h3 {
    font-size: clamp(1.4rem, 2.5vw, 1.8rem);
    margin-bottom: 4px;
}

.featured-subtitle {
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
}

.featured-desc {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-lg);
    max-width: 680px;
}

.featured-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: var(--space-lg);
}

.featured-links {
    display: flex;
    gap: var(--space-md);
    flex-wrap: wrap;
    margin-bottom: var(--space-lg);
}

/* Architecture callout */
.callout {
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.7;
    color: var(--code);
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: var(--radius-sm);
    padding: var(--space-md) var(--space-lg);
}

/* ---- Tags / Badges ---- */
.tag {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 11px;
    padding: 4px 10px;
    border-radius: 3px;
    background: var(--accent-soft);
    color: var(--accent);
    font-weight: 500;
    letter-spacing: 0.02em;
}

/* ---- Project Grid ---- */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--space-lg);
}

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: var(--space-lg);
    transition: all var(--transition);
    display: flex;
    flex-direction: column;
}

.project-card:hover {
    transform: translateY(-3px);
    border-color: var(--accent);
    box-shadow: 0 0 0 1px var(--accent-glow), var(--shadow-lg);
}

/* Card Header with Icon */
.project-card-header {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-md);
}

.project-icon {
    width: 48px;
    min-width: 48px;
    max-width: 48px;
    height: 48px;
    min-height: 48px;
    max-height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    overflow: hidden;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    transition: border-color var(--transition);
}

.project-card:hover .project-icon {
    border-color: var(--accent);
}

.project-icon img {
    display: block;
    width: 48px;
    height: 48px;
    max-width: 48px;
    max-height: 48px;
    object-fit: cover;
}

.project-icon svg {
    width: 26px;
    height: 26px;
    flex-shrink: 0;
    color: var(--accent);
}

.project-icon--emoji {
    font-size: 24px;
    line-height: 1;
}

.project-card-header h3 {
    font-size: 1.05rem;
    margin-bottom: 2px;
}

.project-card-tagline {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--text-muted);
}

/* Featured header with icon */
.featured-header {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    margin-bottom: var(--space-md);
}

.featured-icon {
    width: 64px;
    min-width: 64px;
    max-width: 64px;
    height: 64px;
    min-height: 64px;
    max-height: 64px;
    border-radius: 14px;
    flex-shrink: 0;
    overflow: hidden;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    transition: border-color var(--transition);
}

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

.featured-icon img {
    display: block;
    width: 64px;
    height: 64px;
    max-width: 64px;
    max-height: 64px;
    object-fit: cover;
}

.project-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-md);
    flex: 1;
}

.project-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: var(--space-md);
}

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

.card-link {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    color: var(--accent);
    transition: color var(--transition-fast);
}

.card-link:hover {
    color: var(--accent-hover);
    text-decoration: underline;
}

/* ---- Skills Section ---- */
.skills-category {
    margin-bottom: var(--space-xl);
}

.skills-category:last-child {
    margin-bottom: 0;
}

.skills-category-label {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--text-muted);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    margin-bottom: var(--space-md);
}

.skills-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-badge {
    font-family: var(--font-mono);
    font-size: 12px;
    padding: 6px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    background: transparent;
}

.skill-badge:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: var(--accent-soft);
}

/* ---- Systems Thinking Section ---- */
.systems-text {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    max-width: 680px;
    margin-bottom: var(--space-2xl);
}

.systems-text em {
    color: var(--accent);
    font-style: normal;
    font-weight: 600;
}

.principles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: var(--space-md);
}

.principle-card {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: var(--space-lg);
    transition: all var(--transition);
    background: var(--bg-card);
}

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

.principle-card h4 {
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: var(--space-sm);
    line-height: 1.4;
}

.principle-card p {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ---- Publications ---- */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--space-lg);
}

.book-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: var(--space-lg);
    transition: all var(--transition);
}

.book-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.book-card h3 {
    font-size: 1.05rem;
    margin-bottom: 4px;
}

.book-meta {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: var(--space-md);
}

.book-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-md);
}

.book-link {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    color: var(--accent);
}

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

/* ---- Available For / Hire ---- */
.hire-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: var(--space-md);
    margin-bottom: var(--space-2xl);
}

.hire-item {
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--text-secondary);
    padding: var(--space-md) var(--space-lg);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

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

.contact-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.contact-link {
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
}

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

.contact-link-label {
    font-size: 11px;
    color: var(--text-muted);
    min-width: 60px;
}

/* ---- Footer ---- */
.footer {
    border-top: 1px solid var(--border);
    padding: 40px 0;
    text-align: center;
    transition: border-color var(--transition);
}

.footer-copy {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: var(--space-sm);
    font-family: var(--font-mono);
}

.footer-legal {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
}

.footer-legal a {
    color: var(--text-muted);
    transition: color var(--transition-fast);
}

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

.footer-memento {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.2em;
    color: var(--text-muted);
    cursor: pointer;
    user-select: none;
    transition: color var(--transition-fast);
    display: inline-block;
}

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

/* Game of Life Canvas */
.gol-canvas-wrap {
    margin-top: var(--space-lg);
    display: none;
    justify-content: center;
}

.gol-canvas-wrap.active {
    display: flex;
}

#golCanvas {
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
}

/* ---- Animations ---- */
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(16px); }
    to   { opacity: 1; transform: translateY(0); }
}

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

.fade-in {
    opacity: 0;
    transform: translateY(14px);
    transition: opacity 0.4s ease, transform 0.4s ease;
}

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

/* Staggered children */
.stagger > .fade-in:nth-child(1) { transition-delay: 0.04s; }
.stagger > .fade-in:nth-child(2) { transition-delay: 0.08s; }
.stagger > .fade-in:nth-child(3) { transition-delay: 0.12s; }
.stagger > .fade-in:nth-child(4) { transition-delay: 0.16s; }
.stagger > .fade-in:nth-child(5) { transition-delay: 0.20s; }
.stagger > .fade-in:nth-child(6) { transition-delay: 0.24s; }

/* ---- Focus (Accessibility) ---- */
:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* ---- Reduced Motion ---- */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
    .fade-in { opacity: 1; transform: none; }
    .terminal-cursor { animation: none; opacity: 1; }
}

/* ============================================================
 * RESPONSIVE
 * ============================================================ */

@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-links.open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--bg);
        border-bottom: 1px solid var(--border);
        padding: var(--space-md) var(--space-lg);
        gap: var(--space-md);
    }
    .nav-menu-btn { display: block; }

    .mode-toggle-wrap {
        top: 12px;
        right: 12px;
        padding: 4px 10px 4px 4px;
    }

    .hero { min-height: 85vh; padding-top: calc(var(--nav-height) + 20px); }
    .project-grid { grid-template-columns: 1fr; }
    .principles-grid { grid-template-columns: 1fr; }
    .books-grid { grid-template-columns: 1fr; }
    .hire-grid { grid-template-columns: 1fr 1fr; }
    section { padding: 64px 0; }
    .featured { padding: var(--space-lg); }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 1.8rem; }
    .hero-links { flex-direction: column; }
    .hero-link { text-align: center; }
    .container { padding: 0 var(--space-md); }
    .hire-grid { grid-template-columns: 1fr; }
    .featured-links { flex-direction: column; }
}