/* ===================================
   FABIBLE - CHIP DESIGN SOFTWARE
   Color Palette: Monochrome Only
   =================================== */

:root {
    --black: #000000;
    --white: #FFFFFF;
    --gray-light: #F5F5F5;
    --gray-medium: #666666;
    --gray-dark: #333333;
    --gray-darker: #222222;
    
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Montserrat', sans-serif;
    
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===================================
   GLOBAL STYLES
   =================================== */

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    color: var(--gray-dark);
    background-color: var(--white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

section {
    padding: 6rem 0;
}

/* ===================================
   TYPOGRAPHY
   =================================== */

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--black);
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 4rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

/* ===================================
   BUTTONS
   =================================== */

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 0;
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid var(--black);
    text-align: center;
}

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

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

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

.btn-outline:hover {
    background-color: var(--black);
    color: var(--white);
}

.btn-text {
    background-color: transparent;
    color: var(--gray-dark);
    border: none;
    padding: 0.875rem 0;
    font-weight: 500;
}

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

.btn-submit {
    background-color: var(--black);
    color: var(--white);
    width: 100%;
    max-width: 300px;
    margin: 2rem auto 0;
    display: block;
}

.btn-submit:hover {
    background-color: var(--white);
    color: var(--black);
}

/* ===================================
   NAVIGATION
   =================================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--white);
    border-bottom: 1px solid var(--gray-light);
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.05);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-heading);
    font-weight: 800;
    font-size: 1.5rem;
    letter-spacing: 0.05em;
    color: var(--black);
}

.logo-icon {
    color: var(--black);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2.5rem;
}

.nav-link {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--gray-dark);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover {
    color: var(--black);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--black);
    transition: var(--transition);
}

.nav-link:hover::after {
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 2px;
    background-color: var(--black);
    transition: var(--transition);
}

/* ===================================
   HERO SECTION
   =================================== */

.hero {
    padding: 10rem 0 8rem;
    background-color: var(--white);
    margin-top: 70px;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.hero-tagline {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--gray-medium);
    margin-bottom: 1.5rem;
}

.hero-title {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    letter-spacing: -0.03em;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--gray-dark);
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

.hero-differentiator {
    font-size: 1.125rem;
    color: var(--gray-medium);
    margin-bottom: 3rem;
    font-style: italic;
}

.hero-cta {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.hero-visual {
    margin-top: 6rem;
    display: flex;
    justify-content: center;
}

.circuit-diagram {
    width: 100%;
    max-width: 600px;
    height: auto;
    color: var(--gray-dark);
    opacity: 0.6;
}

/* ===================================
   PROBLEM STATEMENT SECTION
   =================================== */

.problem-statement {
    background-color: var(--gray-light);
}

.problem-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
}

.problem-card {
    background-color: var(--white);
    padding: 3rem;
    border: 2px solid var(--black);
    transition: var(--transition);
}

.problem-card:hover {
    transform: translateY(-5px);
    box-shadow: 8px 8px 0 var(--black);
}

.problem-heading {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--black);
}

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

.problem-list li {
    font-size: 1.125rem;
    line-height: 2;
    color: var(--gray-dark);
    font-weight: 400;
}

/* ===================================
   SOLUTION SECTION
   =================================== */

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

.solution-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 3rem;
}

.solution-card {
    text-align: center;
    padding: 2rem;
    transition: var(--transition);
}

.solution-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--black);
    color: var(--black);
}

.solution-card:hover .solution-icon {
    background-color: var(--black);
    color: var(--white);
}

.solution-heading {
    font-size: 1.375rem;
    margin-bottom: 1rem;
}

.solution-text {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--gray-medium);
}

/* ===================================
   TECHNICAL DIFFERENTIATORS
   =================================== */

.technical-diff {
    background-color: var(--black);
    color: var(--white);
}

.technical-diff .section-title {
    color: var(--white);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    border: 1px solid var(--gray-medium);
    transition: var(--transition);
}

.feature-item:hover {
    border-color: var(--white);
    background-color: rgba(255, 255, 255, 0.05);
}

.feature-icon {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--white);
    flex-shrink: 0;
}

.feature-text {
    font-size: 1.125rem;
    line-height: 1.6;
    color: var(--gray-light);
}

/* ===================================
   TARGET USERS
   =================================== */

.target-users {
    background-color: var(--gray-light);
}

.users-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.user-card {
    background-color: var(--white);
    padding: 3rem 2rem;
    text-align: center;
    border: 1px solid var(--gray-dark);
    transition: var(--transition);
}

.user-card:hover {
    border-color: var(--black);
    border-width: 2px;
}

.user-heading {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--black);
}

.user-text {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--gray-medium);
}

/* ===================================
   ROADMAP / TIMELINE
   =================================== */

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

.timeline {
    max-width: 900px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 0;
    bottom: 0;
    width: 2px;
    background-color: var(--gray-dark);
}

.timeline-item {
    display: flex;
    gap: 2rem;
    margin-bottom: 3rem;
    position: relative;
}

.timeline-marker {
    width: 40px;
    height: 40px;
    background-color: var(--black);
    border: 4px solid var(--white);
    box-shadow: 0 0 0 2px var(--black);
    border-radius: 0;
    flex-shrink: 0;
    position: relative;
    z-index: 1;
}

.timeline-content {
    flex: 1;
    padding: 0.5rem 0;
}

.timeline-heading {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.timeline-text {
    font-size: 1.125rem;
    line-height: 1.6;
    color: var(--gray-medium);
}

/* ===================================
   EARLY ACCESS CTA
   =================================== */

.early-access {
    background-color: var(--gray-darker);
    color: var(--white);
    padding: 6rem 0;
}

.cta-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--white);
}

.access-form {
    max-width: 700px;
    margin: 0 auto;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

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

.form-group input,
.form-group select {
    padding: 1rem;
    font-family: var(--font-body);
    font-size: 1rem;
    border: 2px solid var(--gray-medium);
    background-color: var(--white);
    color: var(--gray-dark);
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--white);
}

.form-group select {
    cursor: pointer;
}

.form-message {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.9375rem;
    color: var(--gray-light);
}

.form-message.success {
    color: var(--white);
}

.form-message.error {
    color: var(--gray-light);
}

/* ===================================
   FOOTER
   =================================== */

.footer {
    background-color: var(--black);
    color: var(--gray-light);
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-brand {
    grid-column: span 1;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-heading);
    font-weight: 800;
    font-size: 1.5rem;
    letter-spacing: 0.05em;
    color: var(--white);
    margin-bottom: 1rem;
}

.footer-tagline {
    font-size: 0.875rem;
    color: var(--gray-medium);
    font-style: italic;
}

.footer-heading {
    font-size: 0.875rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 1rem;
    color: var(--white);
}

.footer-column {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-link {
    color: var(--gray-medium);
    text-decoration: none;
    font-size: 0.9375rem;
    transition: var(--transition);
}

.footer-link:hover {
    color: var(--white);
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 0.5rem;
}

.social-link {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--gray-medium);
    color: var(--gray-medium);
    transition: var(--transition);
}

.social-link:hover {
    border-color: var(--white);
    color: var(--white);
    background-color: rgba(255, 255, 255, 0.1);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--gray-dark);
}

.copyright {
    font-size: 0.875rem;
    color: var(--gray-medium);
}

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

@media (max-width: 768px) {
    .container {
        padding: 0 1.5rem;
    }
    
    section {
        padding: 4rem 0;
    }
    
    /* Navigation */
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background-color: var(--white);
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 2rem;
        border-bottom: 1px solid var(--gray-light);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-link {
        padding: 1rem 0;
        border-bottom: 1px solid var(--gray-light);
    }
    
    .nav-link::after {
        display: none;
    }
    
    .nav-menu .btn-outline {
        margin-top: 1rem;
        text-align: center;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(7px, 7px);
    }
    
    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
    
    /* Hero */
    .hero {
        padding: 6rem 0 4rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.125rem;
    }
    
    .hero-differentiator {
        font-size: 1rem;
    }
    
    .hero-cta {
        flex-direction: column;
        gap: 1rem;
    }
    
    .hero-cta .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .hero-visual {
        margin-top: 4rem;
    }
    
    /* Sections */
    .section-title {
        font-size: 2rem;
        margin-bottom: 3rem;
    }
    
    .problem-grid,
    .solution-grid,
    .users-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .problem-card {
        padding: 2rem;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
    
    /* Timeline */
    .timeline::before {
        left: 10px;
    }
    
    .timeline-item {
        gap: 1rem;
    }
    
    .timeline-marker {
        width: 20px;
        height: 20px;
        border-width: 2px;
    }
    
    .timeline-heading {
        font-size: 1.25rem;
    }
    
    .timeline-text {
        font-size: 1rem;
    }
    
    /* CTA */
    .cta-title {
        font-size: 1.75rem;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    /* Footer */
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .hero-title {
        font-size: 3.5rem;
    }
    
    .solution-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ===================================
   ANIMATIONS
   =================================== */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.8s ease-out forwards;
}

/* Smooth scroll padding for fixed nav */
html {
    scroll-padding-top: 80px;
}

/* Selection */
::selection {
    background-color: var(--black);
    color: var(--white);
}

::-moz-selection {
    background-color: var(--black);
    color: var(--white);
}