/* 
 * Flyinghash | Minimal Editorial CSS 
 * Pure CSS3 - No frameworks
 */

/* =========================================
   1. RESET & BASE
   ========================================= */
:root {
    /* Colors */
    --color-bg: #ffffff;
    --color-bg-alt: #f4f4f5;
    --color-bg-dark: #09090b;
    --color-text: #18181b;
    --color-text-muted: #71717a;
    --color-text-light: #fafafa;
    --color-text-light-muted: #a1a1aa;
    --color-border: #e4e4e7;
    --color-border-dark: #27272a;
    --color-accent: #2563eb;
    
    /* Typography */
    --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    
    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 8rem;
    
    /* Layout */
    --container-max: 1200px;
    --header-height: 80px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    font-family: var(--font-sans);
    scroll-behavior: smooth;
    font-size: 16px;
    line-height: 1.5;
    color: var(--color-text);
    background-color: var(--color-bg);
}

body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

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

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

button, input, select, textarea {
    font: inherit;
    color: inherit;
}

/* =========================================
   2. TYPOGRAPHY
   ========================================= */
h1, h2, h3, h4, h5, h6 {
    line-height: 1.1;
    font-weight: 600;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(3rem, 6vw, 5rem);
    margin-bottom: var(--space-sm);
}

h2 {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: var(--space-md);
}

h3 {
    font-size: 1.5rem;
    margin-bottom: var(--space-xs);
}

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

.text-accent {
    color: var(--color-text-muted);
    font-weight: 400;
}

/* =========================================
   3. LAYOUT & UTILITIES
   ========================================= */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

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

.bg-dark {
    background-color: var(--color-bg-dark);
    color: var(--color-text-light);
}

.text-light h2, .text-light h3 {
    color: var(--color-text-light);
}

.bg-gray {
    background-color: var(--color-bg-alt);
}

/* =========================================
   4. COMPONENTS
   ========================================= */
/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    font-size: 1rem;
    border-radius: 4px;
    cursor: pointer;
    transition: transform var(--transition-fast), background-color var(--transition-fast), color var(--transition-fast);
    border: 1px solid transparent;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background-color: var(--color-text);
    color: var(--color-bg);
}

.btn-primary:hover {
    background-color: var(--color-text-muted);
}

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

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

/* =========================================
   5. HEADER & NAVIGATION
   ========================================= */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    z-index: 100;
    background-color: rgba(255, 255, 255, 0);
    backdrop-filter: blur(0px);
    transition: background-color var(--transition-base), backdrop-filter var(--transition-base), border-bottom var(--transition-base);
    border-bottom: 1px solid transparent;
}

.header.scrolled {
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--color-border);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo {
    display: inline-flex;
    align-items: center;
}

.logo img {
    height: 32px;
    width: auto;
}

.nav-desktop {
    display: none;
    gap: 2rem;
}

.nav-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-muted);
    position: relative;
}

.nav-link:hover, .nav-link.active {
    color: var(--color-text);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 100%;
    height: 1px;
    background-color: var(--color-text);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform var(--transition-base);
}

.nav-link:hover::after, .nav-link.active::after {
    transform: scaleX(1);
    transform-origin: left;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.nav-cta {
    display: none;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* Mobile Menu Button */
.menu-toggle {
    display: block;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 101;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    position: relative;
    transition: background-color 0.2s;
}

.hamburger::before, .hamburger::after {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background-color: var(--color-text);
    left: 0;
    transition: transform var(--transition-base);
}

.hamburger::before { transform: translateY(-6px); }
.hamburger::after { transform: translateY(6px); }

.menu-toggle[aria-expanded="true"] .hamburger {
    background-color: transparent;
}

.menu-toggle[aria-expanded="true"] .hamburger::before {
    transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .hamburger::after {
    transform: rotate(-45deg);
}

/* Mobile Menu Overlay */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: var(--color-bg);
    z-index: 99;
    padding-top: var(--header-height);
    transform: translateY(-100%);
    transition: transform var(--transition-slow);
    display: flex;
    flex-direction: column;
}

.mobile-menu.is-open {
    transform: translateY(0);
}

.mobile-nav {
    display: flex;
    flex-direction: column;
    padding: var(--space-md);
    gap: 1.5rem;
}

.mobile-nav-link {
    font-size: 1.5rem;
    font-weight: 500;
}

.mobile-cta {
    margin-top: 2rem;
    width: 100%;
}

@media (min-width: 768px) {
    .nav-desktop { display: flex; }
    .nav-cta { display: inline-flex; }
    .menu-toggle { display: none; }
    .mobile-menu { display: none; }
}

/* =========================================
   6. SECTIONS
   ========================================= */

/* Hero */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: var(--header-height);
    position: relative;
}

.hero-bg-grid {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(to right, rgba(0,0,0,0.03) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(0,0,0,0.03) 1px, transparent 1px);
    background-size: 40px 40px;
    z-index: -1;
}

.hero-container {
    max-width: 900px;
}

.eyebrow {
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    margin-bottom: var(--space-sm);
}

.hero-subtitle {
    font-size: clamp(1.125rem, 2vw, 1.5rem);
    color: var(--color-text-muted);
    max-width: 700px;
    margin-bottom: var(--space-md);
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Intro */
.intro-container {
    max-width: 800px;
}

.intro-heading {
    margin-bottom: var(--space-sm);
}

.intro-copy {
    font-size: 1.25rem;
    color: var(--color-text-light-muted);
}

/* Services */
.section-header {
    margin-bottom: var(--space-lg);
    max-width: 600px;
}

.section-subheading {
    font-size: 1.25rem;
    color: var(--color-text-muted);
}

.services-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-md);
    border-top: 1px solid var(--color-border);
}

@media (min-width: 768px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.service-block {
    padding: var(--space-md) 0;
    border-bottom: 1px solid var(--color-border);
}

.service-block p {
    color: var(--color-text-muted);
    margin-bottom: var(--space-sm);
}

.capabilities-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 0.5rem;
}

.capabilities-list li {
    font-size: 0.875rem;
    position: relative;
    padding-left: 1rem;
}

.capabilities-list li::before {
    content: '—';
    position: absolute;
    left: 0;
    color: var(--color-text-muted);
}

/* Problems */
.problems-heading {
    text-align: center;
    margin-bottom: var(--space-lg);
}

.problems-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-width: 800px;
    margin: 0 auto;
}

.problem-item {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    padding: 1.5rem;
    text-align: left;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.problem-item:hover {
    border-color: var(--color-text);
    background-color: var(--color-bg-dark);
    color: var(--color-bg);
}

.problem-text {
    font-size: 1.25rem;
    font-weight: 500;
}

.problem-arrow {
    transition: transform var(--transition-fast);
}

.problem-item:hover .problem-arrow {
    transform: translateX(4px);
}

/* Approach */
.section-heading-large {
    font-size: clamp(3rem, 8vw, 6rem);
    line-height: 1;
    margin-bottom: var(--space-lg);
}

.approach-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-lg);
}

@media (min-width: 768px) {
    .approach-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .approach-steps {
        grid-template-columns: repeat(3, 1fr);
    }
}

.step {
    border-top: 2px solid var(--color-text);
    padding-top: var(--space-sm);
}

.step-num {
    font-family: monospace;
    font-size: 1rem;
    color: var(--color-text-muted);
    margin-bottom: var(--space-xs);
}

.step-content p {
    color: var(--color-text-muted);
}

/* Intelligence */
.intel-header {
    text-align: center;
    margin-bottom: var(--space-lg);
}

.intel-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-light-muted);
}

.intel-explanation {
    max-width: 600px;
    margin: 0 auto var(--space-xl);
    text-align: center;
    font-size: 1.125rem;
}

.intel-diagram {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

@media (min-width: 768px) {
    .intel-diagram {
        flex-direction: row;
        justify-content: space-between;
    }
}

.diagram-node {
    border: 1px solid var(--color-border-dark);
    padding: 1.5rem;
    text-align: center;
    width: 200px;
    background-color: rgba(255,255,255,0.05);
}

.node-title {
    font-weight: 600;
    letter-spacing: 0.1em;
    margin-bottom: 0.5rem;
}

.node-desc {
    font-size: 0.875rem;
    color: var(--color-text-light-muted);
}

.diagram-line {
    width: 2px;
    height: 40px;
    background-color: var(--color-border-dark);
}

@media (min-width: 768px) {
    .diagram-line {
        width: 100%;
        height: 2px;
        flex-grow: 1;
    }
}

/* Work */
.work-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-lg);
    margin-top: var(--space-lg);
}

@media (min-width: 768px) {
    .work-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

.case-study {
    border: 1px solid var(--color-border);
    padding: var(--space-md);
    display: flex;
    flex-direction: column;
}

.case-meta {
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    margin-bottom: var(--space-md);
}

.case-problem, .case-solution {
    font-size: 1rem;
}

.case-desc {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--space-sm);
}

.case-outcome {
    margin-top: auto;
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
}

.outcome-metric {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1;
    margin-bottom: 0.25rem;
}

.outcome-label {
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

/* About */
.about-container {
    max-width: 800px;
}

.about-copy {
    font-size: clamp(1.125rem, 2vw, 1.5rem);
    color: var(--color-text-muted);
}

/* Contact */
.contact-container {
    max-width: 600px;
}

.contact-header {
    margin-bottom: var(--space-lg);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-row {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

@media (min-width: 600px) {
    .form-row {
        flex-direction: row;
    }
    .form-row .form-group {
        flex: 1;
    }
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

label {
    font-size: 0.875rem;
    font-weight: 500;
}

input, select, textarea {
    padding: 0.75rem;
    border: 1px solid var(--color-border);
    background-color: var(--color-bg);
    border-radius: 4px;
    transition: border-color var(--transition-fast);
    outline: none;
}

input:focus, select:focus, textarea:focus {
    border-color: var(--color-text);
}

.error-msg {
    color: #dc2626;
    font-size: 0.75rem;
    display: none;
}

.form-group.has-error input,
.form-group.has-error select,
.form-group.has-error textarea {
    border-color: #dc2626;
}

.form-group.has-error .error-msg {
    display: block;
}

.submit-btn {
    width: 100%;
    margin-top: 1rem;
}

.success-msg {
    display: none;
    padding: 1rem;
    background-color: #dcfce7;
    color: #166534;
    border-radius: 4px;
    text-align: center;
    font-weight: 500;
}

.success-msg.show {
    display: block;
}

/* Footer */
.footer {
    border-top: 1px solid var(--color-border);
    padding: var(--space-lg) 0 var(--space-md);
}

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

@media (min-width: 768px) {
    .footer-container {
        flex-direction: row;
        justify-content: space-between;
        flex-wrap: wrap;
    }
}

.footer-brand {
    flex: 1;
    min-width: 250px;
}

.footer-tagline {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    margin-top: 0.5rem;
}

.footer-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

@media (min-width: 600px) {
    .footer-nav {
        flex-direction: row;
        gap: 1.5rem;
    }
}

.footer-nav a {
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

.footer-nav a:hover {
    color: var(--color-text);
}

.footer-bottom {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    border-top: 1px solid var(--color-border);
    padding-top: var(--space-md);
    margin-top: var(--space-md);
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

@media (min-width: 600px) {
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
    }
}

.social-links {
    display: flex;
    gap: 1rem;
}

/* =========================================
   7. ACCESSIBILITY & MOTION
   ========================================= */
:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

@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;
        scroll-behavior: auto !important;
    }
}