/* 
 * Outliers School & Consultancy
 * Design System: Selective Consultancy
 * 
 * Palette:
 * - Primary (text): #1A1A1A (near-black)
 * - Background: #FAF8F5 (warm off-white)
 * - Accent: #2D5A4A (deep forest green)
 * - Secondary: #8B8680 (muted stone)
 * - Border: #E5E2DE (warm gray)
 * 
 * Typography:
 * - Headlines: Playfair Display (editorial serif)
 * - Body: Inter (clean sans)
 * - Labels: JetBrains Mono (sparingly, for framework names)
 */

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

/* ===== CSS Variables ===== */
:root {
    /* Colors */
    --color-primary: #1A1A1A;
    --color-background: #FAF8F5;
    --color-accent: #2D5A4A;
    --color-accent-hover: #234840;
    --color-secondary: #8B8680;
    --color-border: #E5E2DE;
    --color-white: #FFFFFF;
    --color-card-shadow: rgba(0, 0, 0, 0.06);
    
    /* Typography */
    --font-headline: 'Playfair Display', Georgia, 'Times New Roman', serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    
    /* 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;
    
    /* Line Heights */
    --leading-tight: 1.25;
    --leading-snug: 1.375;
    --leading-normal: 1.5;
    --leading-relaxed: 1.625;
    
    /* 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;
    --space-24: 6rem;
    
    /* Container */
    --container-max: 1200px;
    --container-narrow: 800px;
    --container-padding: 1.5rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
}

/* ===== Base Styles ===== */
html {
    font-size: 16px;
    scroll-behavior: smooth;
    scroll-padding-top: 80px; /* Offset for sticky navigation */
}

body {
    font-family: var(--font-body);
    font-size: var(--text-base);
    line-height: var(--leading-relaxed);
    color: var(--color-primary);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-headline);
    font-weight: 500;
    line-height: var(--leading-tight);
    color: var(--color-primary);
}

h1 {
    font-size: var(--text-4xl);
    letter-spacing: -0.02em;
}

h2 {
    font-size: var(--text-3xl);
    letter-spacing: -0.01em;
}

h3 {
    font-size: var(--text-2xl);
}

h4 {
    font-size: var(--text-xl);
}

p {
    margin-bottom: var(--space-4);
}

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

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

.text-accent {
    color: var(--color-accent);
}

.text-sm {
    font-size: var(--text-sm);
}

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

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

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

/* ===== Container ===== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding-left: var(--container-padding);
    padding-right: var(--container-padding);
}

.container--narrow {
    max-width: var(--container-narrow);
}

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

.section--hero {
    padding: var(--space-1) 0 var(--space-16);
}

.section--alt {
    background-color: var(--color-white);
}

/* Reduce spacing when section--alt follows another section--alt */
.section--alt + .section--alt {
    padding-top: var(--space-4);
}

/* Specifically reduce spacing for About section following Methodology */
#methodology {
    padding-bottom: var(--space-8);
}

#methodology + #about {
    padding-top: var(--space-4);
}

.section__header {
    margin-bottom: var(--space-10);
}

.section__title {
    margin-bottom: var(--space-4);
}

.section__subtitle {
    font-size: var(--text-lg);
    color: var(--color-secondary);
    max-width: 600px;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-body);
    font-size: var(--text-base);
    font-weight: 500;
    line-height: 1;
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

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

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

.btn--secondary:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.btn--lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--text-lg);
}

/* ===== Cards ===== */
.card {
    background-color: var(--color-white);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.card--hover {
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

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

/* ===== Grid Layouts ===== */
.grid {
    display: grid;
    gap: var(--space-6);
}

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

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

.grid--4 {
    grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 1024px) {
    .grid--4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .grid--2,
    .grid--3,
    .grid--4 {
        grid-template-columns: 1fr;
    }
}

/* ===== Flex Utilities ===== */
.flex {
    display: flex;
}

.flex--center {
    align-items: center;
    justify-content: center;
}

.flex--between {
    justify-content: space-between;
}

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

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

/* ===== Spacing Utilities ===== */
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

/* ===== Labels (Mono) ===== */
.label {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-secondary);
}

/* ===== Divider ===== */
.divider {
    height: 1px;
    background-color: var(--color-border);
    margin: var(--space-8) 0;
}

/* ===== Lists ===== */
.list {
    list-style: none;
}

.list--spaced li {
    margin-bottom: var(--space-3);
}

.list--spaced li:last-child {
    margin-bottom: 0;
}

.list--check li {
    position: relative;
    padding-left: var(--space-6);
}

.list--check li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.5em;
    width: 6px;
    height: 6px;
    background-color: var(--color-accent);
    border-radius: 50%;
}

/* ===== Metrics Row ===== */
.metrics {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-6);
}

.metric {
    text-align: center;
}

.metric__value {
    font-family: var(--font-headline);
    font-size: var(--text-3xl);
    font-weight: 500;
    color: var(--color-primary);
    line-height: 1;
    margin-bottom: var(--space-1);
}

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

/* ===== Nav ===== */
.nav {
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4) 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav__logo {
    height: 40px;
    width: auto;
}

.nav__links {
    display: flex;
    gap: var(--space-6);
    list-style: none;
}

.nav__link {
    color: var(--color-secondary);
    font-size: var(--text-sm);
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

.nav__link--cta {
    background: var(--color-accent);
    color: var(--color-white);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast), transform var(--transition-fast);
}

.nav__link--cta:hover {
    background: var(--color-primary);
    color: var(--color-white);
    transform: translateY(-1px);
}

/* Mobile Nav Toggle */
.nav__toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 101;
}

.nav__toggle-bar {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--color-primary);
    border-radius: 2px;
    transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* Hamburger animation when open */
.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.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: translateY(-7px) rotate(-45deg);
}

/* Mobile Nav Styles */
@media (max-width: 768px) {
    .nav__toggle {
        display: flex;
    }
    
    .nav__links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        flex-direction: column;
        background: var(--color-white);
        padding: calc(var(--space-8) + 60px) var(--space-6) var(--space-8) var(--space-6);
        gap: var(--space-4);
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.1);
        transition: right var(--transition-base);
        z-index: 100;
    }
    
    .nav__links--open {
        right: 0;
    }
    
    .nav__link {
        font-size: var(--text-base);
        padding: var(--space-3) 0;
        border-bottom: 1px solid var(--color-border);
    }
    
    .nav__link--cta {
        text-align: center;
        margin-top: var(--space-4);
        border-bottom: none;
        padding: var(--space-2) var(--space-4) !important;
        font-size: var(--text-sm) !important;
        line-height: 1.3;
        display: block;
        box-sizing: border-box;
    }
    
    /* Overlay */
    .nav__overlay {
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.4);
        opacity: 0;
        visibility: hidden;
        transition: opacity var(--transition-base), visibility var(--transition-base);
        z-index: 99;
    }
    
    .nav__overlay--visible {
        opacity: 1;
        visibility: visible;
    }
}

/* ===== Footer ===== */
.footer {
    background-color: var(--color-white);
    border-top: 1px solid var(--color-border);
    padding: var(--space-12) 0 var(--space-8);
}

.footer__disclaimer {
    font-size: var(--text-sm);
    color: var(--color-secondary);
    font-style: italic;
    max-width: 600px;
    margin-top: var(--space-6);
}

/* ===== Responsive Typography ===== */
@media (max-width: 768px) {
    h1 {
        font-size: var(--text-3xl);
    }
    
    h2 {
        font-size: var(--text-2xl);
    }
    
    .section {
        padding: var(--space-12) 0;
    }
    
    .section--hero {
        padding: var(--space-12) 0 var(--space-10);
    }
}

/* ===== Animation: Fade In ===== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeIn 0.6s ease forwards;
}

/* ===== Print Styles ===== */
@media print {
    .nav,
    .footer {
        display: none;
    }
    
    .section {
        padding: var(--space-4) 0;
    }
}