/* ============================================================================
   Adrian Frutiger Case Study Website
   Minimal, rational, typography-driven design inspired by Swiss modernism
   ============================================================================ */

/* ============================================================================
   Reset & Base Styles
   ============================================================================ */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: #1a1a1a;
    background-color: #fafaf9;
    letter-spacing: 0;
}

/* ============================================================================
   Typography System
   ============================================================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.01em;
}

p {
    margin: 1.5rem 0;
    font-size: 1rem;
    line-height: 1.7;
}

/* ============================================================================
   Sidebar Navigation
   ============================================================================ */

.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 240px;
    height: 100vh;
    background-color: #fafaf9;
    border-right: 1px solid #f0f0ed;
    padding: 2.5rem 1.5rem;
    overflow-y: auto;
    z-index: 1000;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    margin-bottom: 3rem;
    color: #1a1a1a;
    display: block;
}

.navigation {
    display: flex;
    flex-direction: column;
}

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

.nav-link {
    display: block;
    padding: 0.75rem 0;
    font-size: 0.85rem;
    line-height: 1.5;
    color: #9a9a96;
    text-decoration: none;
    letter-spacing: 0.02em;
    border-left: 2px solid transparent;
    padding-left: 0.75rem;
    transition: all 0.3s ease;
}

.nav-link:hover {
    color: #4a4a46;
}

.nav-link.active {
    color: #000;
    border-left-color: #000;
    font-weight: 700;
}

/* ============================================================================
   Main Content Area
   ============================================================================ */

.main-content {
    margin-left: 240px;
    padding: 0;
}

.section {
    padding: 6rem 5rem;
    max-width: 1100px;
    margin: 0 auto;
}

/* ============================================================================
   Section Labels and Headers
   ============================================================================ */

.section-label {
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #c5c5c0;
    margin-bottom: 2rem;
    display: block;
}

.section-header {
    margin-bottom: 2.5rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: #000;
    margin-bottom: 1rem;
    line-height: 1.15;
}

/* ============================================================================
   Hero Section
   ============================================================================ */

.section-hero {
    padding: 4rem 5rem;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: flex-start;
    margin-bottom: 3rem;
}

.hero-text {
    padding-top: 0;
}

.hero-title {
    font-size: 6rem;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 2.5rem;
    letter-spacing: -0.04em;
    color: #000;
}

.hero-intro {
    font-size: 0.8rem;
    line-height: 1.8;
    margin-bottom: 1.75rem;
    font-weight: 500;
    color: #2a2a2a;
}

.hero-secondary {
    font-size: 0.7rem;
    line-height: 1.75;
    color: #8a8a86;
    font-weight: 400;
    margin: 0;
}

.hero-image-wrapper {
    position: relative;
    overflow: hidden;
    border-radius: 0;
    background-color: transparent;
    aspect-ratio: 3 / 4;
}

.hero-image {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Metadata Grid */

.metadata-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 3rem;
    margin: 4rem 0;
    padding: 2.5rem 0;
    border-top: 1px solid #f0f0ed;
    border-bottom: 1px solid #f0f0ed;
}

.metadata-item {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.metadata-label {
    font-size: 0.65rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #b5b5b0;
}

.metadata-value {
    font-size: 1.3rem;
    font-weight: 800;
    color: #000;
    line-height: 1.1;
}

.metadata-location {
    font-size: 0.8rem;
    color: #7a7a76;
    font-weight: 400;
    margin-top: 0.25rem;
}

/* Design Philosophy */

.design-philosophy {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 3.5rem;
    margin-top: 5rem;
}

.philosophy-item {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.philosophy-label {
    font-size: 0.95rem;
    font-weight: 700;
    color: #000;
}

.philosophy-text {
    font-size: 0.85rem;
    line-height: 1.7;
    color: #8a8a86;
    margin: 0;
}

/* ============================================================================
   About Section
   ============================================================================ */

.about-container {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.about-text {
    column-count: 1;
}

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
    line-height: 1.8;
}

.about-image-overlay {
    position: relative;
    background-color: transparent;
    border-radius: 0;
    overflow: hidden;
    aspect-ratio: 3 / 4;
}

.about-image {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.about-overlay-metadata {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
    padding: 2rem 1.5rem 1.5rem;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.overlay-meta-item {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.overlay-meta-year {
    font-size: 1.2rem;
    font-weight: 700;
    color: #fff;
    line-height: 1;
}

.overlay-meta-label {
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: rgba(255,255,255,0.8);
}

.timeline {
    margin-top: 3rem;
}

.timeline-title {
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #a5a59f;
    margin-bottom: 1.5rem;
}

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

.timeline-list li {
    padding: 1.25rem 0;
    font-size: 0.85rem;
    line-height: 1.7;
    color: #8a8a86;
    border-bottom: 1px solid #f0f0ed;
    display: grid;
    grid-template-columns: 80px 1fr;
    gap: 1.5rem;
}

.timeline-list li:last-child {
    border-bottom: none;
}

.timeline-year {
    font-weight: 700;
    color: #000;
    flex-shrink: 0;
}

.timeline-event {
    color: #8a8a86;
}

.timeline-event strong {
    color: #000;
    font-weight: 700;
}

/* ============================================================================
   Contribution Section
   ============================================================================ */

.contribution-intro {
    margin-bottom: 2rem;
}

.contribution-subtitle {
    font-size: 0.95rem;
    font-weight: 500;
    color: #7a7a76;
    line-height: 1.6;
    margin: 0;
}

.contribution-text {
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 2.5rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.contribution-text p {
    margin: 0 0 1rem 0;
}

.univers-chart-container {
    margin: 3rem 0;
    background-color: transparent;
    border: none;
    padding: 0;
    border-radius: 0;
}

.univers-chart {
    display: block;
    width: 100%;
    height: auto;
}

.impact-title {
    font-size: 1rem;
    font-weight: 700;
    margin: 2.5rem 0 1.25rem 0;
    color: #1a1a1a;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.contribution-impact {
    margin-top: 2.5rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.contribution-impact p {
    margin: 0 0 1rem 0;
    font-size: 0.9rem;
    line-height: 1.7;
    color: #7a7a76;
}

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

/* ============================================================================
   Influence Section
   ============================================================================ */

.influence-subsection {
    margin-bottom: 3rem;
}

.influence-subtitle {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #000;
}

.influence-subsection p {
    margin: 0 0 1.25rem 0;
    font-size: 0.85rem;
    line-height: 1.8;
    color: #8a8a86;
}

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

.influence-quote-block {
    margin: 3.5rem 0;
    padding: 2.5rem 0;
    border-top: 1px solid #f0f0ed;
    border-bottom: 1px solid #f0f0ed;
}

.influence-quote {
    font-size: 1.05rem;
    line-height: 1.8;
    font-style: italic;
    color: #2a2a2a;
    text-align: center;
    margin: 0;
}

.influence-quote p {
    margin: 0 0 1rem 0;
}

.influence-quote footer {
    font-size: 0.8rem;
    color: #8a8a86;
    font-style: normal;
    margin-top: 1rem;
}

/* ============================================================================
   Typeface Section
   ============================================================================ */

.typeface-subtitle {
    font-size: 0.9rem;
    color: #7a7a76;
    margin-bottom: 2rem;
    font-weight: 400;
}

.typeface-container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 3rem;
    margin-bottom: 2.5rem;
}

.typeface-left {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.typeface-weights {
    background-color: transparent;
    border: none;
    padding: 0;
}

.typeface-section-title {
    font-size: 0.9rem;
    font-weight: 700;
    margin: 1.25rem 0 0.25rem 0;
    color: #000;
}

.typeface-weights p {
    margin: 0 0 0.75rem 0;
    font-size: 0.8rem;
    line-height: 1.6;
    color: #8a8a86;
}

.typeface-weights p:first-of-type {
    margin-top: 0;
}

.typeface-illustration {
    background-color: transparent;
    aspect-ratio: 1;
    border-radius: 0;
    overflow: hidden;
}

.typeface-illustration img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.typeface-right {
    display: flex;
    flex-direction: column;
}

.typeface-characteristics {
    background-color: transparent;
    border: none;
    padding: 0;
}

.characteristics-title {
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #c5c5c0;
    margin-bottom: 2rem;
}

.characteristic-block {
    margin-bottom: 2rem;
}

.characteristic-block:last-child {
    margin-bottom: 0;
}

.characteristic-name {
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: #000;
}

.characteristic-block p {
    font-size: 0.8rem;
    line-height: 1.7;
    color: #8a8a86;
    margin: 0;
}

.key-letterforms {
    background-color: transparent;
    padding: 0;
    margin-bottom: 3rem;
}

.letterforms-title {
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #c5c5c0;
    margin-bottom: 2.5rem;
}

.letterforms-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3rem;
}

.letterform-item {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    text-align: center;
}

.letterform-char {
    font-size: 3.5rem;
    font-weight: 700;
    color: #000;
    line-height: 1;
}

.letterform-name {
    font-size: 0.85rem;
    font-weight: 700;
    color: #000;
    margin: 0;
}

.letterform-item p {
    font-size: 0.75rem;
    line-height: 1.6;
    color: #8a8a86;
    margin: 0;
}

.typeface-wayfinding-section {
    background-color: transparent;
    border: none;
    padding: 0;
}

.wayfinding-subtitle {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #000;
}

.typeface-wayfinding-section p {
    margin: 0 0 1rem 0;
    font-size: 0.85rem;
    line-height: 1.8;
    color: #8a8a86;
}

.typeface-wayfinding-section p:last-child {
    margin-bottom: 0;
}

/* ============================================================================
   Signage Section
   ============================================================================ */

.signage-tagline {
    font-size: 0.9rem;
    color: #7a7a76;
    margin-bottom: 2rem;
    font-weight: 400;
    font-style: italic;
}

.signage-image-container {
    margin: 2.5rem 0;
    background-color: transparent;
    border-radius: 0;
    overflow: hidden;
    aspect-ratio: 16 / 9;
}

.signage-image-container img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.signage-intro-text {
    margin: 3rem 0;
}

.signage-section-title {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #000;
}

.signage-intro-text p {
    margin: 0 0 1.25rem 0;
    font-size: 0.85rem;
    line-height: 1.8;
    color: #8a8a86;
}

.signage-intro-text p:last-child {
    margin-bottom: 0;
}

.wayfinding-system-principles {
    margin: 3.5rem 0;
}

.principles-section-title {
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #c5c5c0;
    margin-bottom: 2.5rem;
}

.principles-grid-layout {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.principle-box {
    background-color: transparent;
    border: none;
    padding: 0 1.5rem 1.5rem 0;
}

.principle-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: #000;
    margin-bottom: 0.5rem;
}

.principle-name {
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: #000;
}

.principle-box p {
    font-size: 0.8rem;
    line-height: 1.7;
    color: #8a8a86;
    margin: 0;
}

.signage-conclusion-text {
    margin-top: 3.5rem;
}

.conclusion-title {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: #000;
}

.signage-conclusion-text p {
    margin: 0 0 1.25rem 0;
    font-size: 0.85rem;
    line-height: 1.8;
    color: #8a8a86;
}

.signage-conclusion-text p:last-child {
    margin-bottom: 0;
}

/* Rectangle Image Between Sections */

.rectangle-image-container {
    width: 100%;
    margin: 2rem 0;
    overflow: hidden;
}

.rectangle-image {
    display: block;
    width: 100%;
    height: auto;
}

/* Airplane Background Image */

.airplane-background-image {
    position: relative;
    margin-bottom: 1.5rem;
    overflow: hidden;
    max-width: 200px;
}

.airplane-bg {
    display: block;
    width: 100%;
    height: auto;
    opacity: 0.15;
}

/* ============================================================================
   Responsive Design
   ============================================================================ */

@media (max-width: 1024px) {
    .sidebar {
        width: 200px;
        padding: 2rem 1.25rem;
    }

    .main-content {
        margin-left: 200px;
    }

    .section {
        padding: 4rem 3rem;
    }

    .section-hero {
        padding: 3rem 3rem;
    }

    .hero-container {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }

    .hero-title {
        font-size: 3rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .metadata-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .design-philosophy {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }

    .about-container {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }

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

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

@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 1px solid #e5e5e0;
        padding: 1.5rem;
        z-index: 1001;
        display: flex;
        justify-content: space-between;
        align-items: center;
        overflow-y: visible;
    }

    .logo {
        margin-bottom: 0;
    }

    .navigation {
        display: none;
    }

    .navigation.active {
        display: flex;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background-color: #fafaf9;
        padding: 1.5rem;
        border-bottom: 1px solid #e5e5e0;
        z-index: 1000;
    }

    .nav-link {
        padding: 0.75rem 0;
    }

    .main-content {
        margin-left: 0;
        margin-top: 60px;
    }

    .section {
        padding: 3rem 1.5rem;
    }

    .section-hero {
        padding: 2rem 1.5rem;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-container {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .metadata-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .design-philosophy {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

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

    .influence-quote-block {
        margin: 1.5rem 0;
        padding: 1.5rem 0;
    }

    .influence-quote {
        font-size: 1rem;
    }

    .letterforms-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .principles-grid-layout {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .typeface-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .sidebar {
        padding: 1rem;
    }

    .logo {
        font-size: 1rem;
    }

    .main-content {
        margin-top: 50px;
    }

    .section {
        padding: 2rem 1rem;
    }

    .section-hero {
        padding: 1.5rem 1rem;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-intro {
        font-size: 0.9rem;
    }

    .section-title {
        font-size: 1.25rem;
    }

    .metadata-grid {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

    .metadata-label {
        font-size: 0.65rem;
    }

    .metadata-value {
        font-size: 1rem;
    }

    .design-philosophy {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

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

    .influence-quote-block {
        padding: 1rem 0;
    }

    .influence-quote {
        font-size: 0.9rem;
    }

    .letterform-char {
        font-size: 2.5rem;
    }

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

    .principles-grid-layout {
        grid-template-columns: 1fr;
    }
}