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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: #FFFFFF;
    color: #111827;
    line-height: 1.6;
}

/* Header */
header {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    padding: 24px 48px;
    z-index: 100;
    background: linear-gradient(to bottom, rgba(0,0,0,0.7), transparent);
}

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

.logo {
    font-size: 32px;
    font-weight: bold;
}

.logo .probler {
    color: #FFFFFF;
}

.logo .ai {
    color: #93BBFC;
}

.sign-in-btn {
    background: #2563EB;
    color: white;
    padding: 8px 24px;
    border: none;
    border-radius: 4px;
    font-size: 14px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.sign-in-btn:hover {
    background: #1E40AF;
}

/* Hero Section - Mobile First Approach */
.hero {
    height: 95vh; /* Partial visibility of next section */
    /* Mobile-first: Load smaller image by default */
    background: linear-gradient(to bottom, rgba(17, 24, 39, 0.5), rgba(17, 24, 39, 0.8)), 
                url('images/centered-confident-man-blue-eyes-mobile.jpg');
    background-size: cover;
    background-position: center center;
    background-repeat: no-repeat;
    /* No fixed attachment on mobile for better performance */
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 24px;
    position: relative;
}

/* Desktop: Load optimized image (JPEG fallback, WebP preferred) */
@media (min-width: 769px) {
    .hero {
        background: linear-gradient(to bottom, rgba(17, 24, 39, 0.4), rgba(17, 24, 39, 0.75)), 
                    url('images/centered-confident-man-blue-eyes-desktop.jpg');
        background-size: cover;
        background-position: center center;
        background-attachment: fixed;
    }
}

/* Use WebP for browsers that support it */
@supports (background-image: url('image.webp')) {
    .hero {
        background-image: linear-gradient(to bottom, rgba(17, 24, 39, 0.5), rgba(17, 24, 39, 0.8)), 
                         url('images/centered-confident-man-blue-eyes-mobile.webp');
    }
    
    @media (min-width: 769px) {
        .hero {
            background-image: linear-gradient(to bottom, rgba(17, 24, 39, 0.4), rgba(17, 24, 39, 0.75)), 
                             url('images/centered-confident-man-blue-eyes-desktop.webp');
        }
    }
}

.hero-content {
    max-width: 800px;
}

.hero h1 {
    font-size: 64px;
    font-weight: bold;
    color: #FFFFFF;
    margin-bottom: 16px;
    animation: fadeInUp 0.8s ease;
}

.hero .subtitle {
    font-size: 24px;
    color: #93BBFC;
    margin-bottom: 32px;
    animation: fadeInUp 0.8s ease 0.2s backwards;
}

.email-form {
    display: flex;
    gap: 0;
    max-width: 500px;
    margin: 0 auto;
    animation: fadeInUp 0.8s ease 0.4s backwards;
}

.email-input {
    flex: 1;
    padding: 16px 24px;
    font-size: 16px;
    border: 1px solid #E5E7EB;
    border-right: none;
    border-radius: 8px 0 0 8px;
    background: rgba(255, 255, 255, 0.95);
}

.cta-button {
    padding: 16px 32px;
    background: #2563EB;
    color: white;
    border: none;
    border-radius: 0 8px 8px 0;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.cta-button:hover {
    background: #1E40AF;
    transform: translateX(4px);
}

.helper-text {
    color: #9CA3AF;
    font-size: 14px;
    margin-top: 16px;
    animation: fadeInUp 0.8s ease 0.6s backwards;
}

/* Scroll Progress Indicator */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, #2563EB 0%, #7c3aed 100%);
    z-index: 1000;
    transition: width 0.1s ease;
}

/* Feature Sections */
.feature-section {
    padding: 80px 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 80px;
    max-width: 1400px;
    margin: 0 auto;
    min-height: 95vh; /* Allow partial visibility */
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
    position: relative; /* For absolute positioning of chevron */
}

.feature-section.visible {
    opacity: 1;
    transform: translateY(0);
}

.feature-section:nth-child(even) {
    flex-direction: row-reverse;
    background: #F9FAFB;
}

.feature-content {
    flex: 1;
    max-width: 500px;
}

.feature-content h2 {
    font-size: 48px;
    font-weight: bold;
    color: #111827;
    margin-bottom: 24px;
    line-height: 1.2;
}

.feature-content p {
    font-size: 18px;
    color: #6B7280;
    line-height: 1.8;
}

.feature-visual {
    flex: 1;
    max-width: 600px;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 20px;
}

.device-label {
    font-size: 14px;
    font-weight: 600;
    color: #6B7280;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Phone Frame Styling (Feature 1) */
.phone-frame {
    position: relative;
    width: 360px;
    height: 780px;
    background: #1a1a1a;
    border-radius: 40px;
    padding: 12px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    margin: 0 auto;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: #FFFFFF;
    border-radius: 28px;
    overflow: hidden;
    position: relative;
    border: none;
}

/* Desktop Frame Styling (Feature 2) */
.desktop-frame {
    position: relative;
    width: 600px;
    height: 400px;
    background: #c0c0c0;
    border-radius: 12px;
    padding: 8px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    margin: 0 auto;
}

.desktop-frame::before {
    content: '';
    position: absolute;
    bottom: -20px;
    left: 50%;
    transform: translateX(-50%);
    width: 150px;
    height: 20px;
    background: #a0a0a0;
    border-radius: 0 0 4px 4px;
}

.desktop-frame::after {
    content: '';
    position: absolute;
    bottom: -40px;
    left: 50%;
    transform: translateX(-50%);
    width: 200px;
    height: 20px;
    background: #c0c0c0;
    border-radius: 4px;
}

.desktop-screen {
    width: 100%;
    height: 100%;
    background: #FFFFFF;
    border-radius: 8px;
    overflow: hidden;
    position: relative;
    border: none;
}

/* Pixel Tablet Frame Styling (Feature 3) */
.tablet-frame {
    position: relative;
    width: 560px;  /* Reduced from 800px (70% of original) */
    height: 350px;  /* Reduced from 500px (70% of original) */
    background: linear-gradient(135deg, #2a2a2a 0%, #1a1a1a 100%);
    border-radius: 20px;  /* Slightly smaller radius */
    padding: 10px;  /* Reduced padding */
    box-shadow: 
        0 20px 50px rgba(0,0,0,0.35),
        inset 0 0 2px rgba(255,255,255,0.1);
    margin: 0 auto;
}

/* Power button on right side */
.tablet-frame::before {
    content: '';
    position: absolute;
    right: -3px;
    top: 85px;  /* Adjusted for smaller frame */
    width: 3px;
    height: 45px;  /* Smaller button */
    background: #1a1a1a;
    border-radius: 0 2px 2px 0;
}

/* Volume buttons on right side */
.tablet-frame::after {
    content: '';
    position: absolute;
    right: -3px;
    top: 140px;  /* Adjusted for smaller frame */
    width: 3px;
    height: 30px;  /* Smaller button */
    background: #1a1a1a;
    border-radius: 0 2px 2px 0;
}

.tablet-screen {
    width: 100%;
    height: 100%;
    background: #000000;
    border-radius: 12px;  /* Smaller radius for smaller frame */
    overflow: hidden;
    position: relative;
    border: none;
}

.dashboard-preview {
    background: linear-gradient(135deg, #2563EB 0%, #1E40AF 100%);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.pattern-overlay {
    position: absolute;
    inset: 0;
    opacity: 0.1;
    background-image: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 35px,
        rgba(255,255,255,.1) 35px,
        rgba(255,255,255,.1) 70px
    );
    animation: slide 20s linear infinite;
}

.dashboard-content {
    color: white;
    text-align: center;
    z-index: 1;
    position: relative;
}

.metric {
    font-size: 48px;
    font-weight: bold;
    margin-bottom: 8px;
}

.metric-label {
    font-size: 14px;
    opacity: 0.8;
}

/* FAQ Section */
.faq-section {
    padding: 80px 48px;
    background: #111827;
    color: white;
    min-height: 90vh; /* Partial visibility */
    position: relative; /* For absolute positioning of chevron */
}

.faq-container {
    max-width: 900px;
    margin: 0 auto;
}

.faq-section h2 {
    font-size: 48px;
    text-align: center;
    margin-bottom: 48px;
}

.faq-item {
    background: #1F2937;
    margin-bottom: 8px;
    border-radius: 4px;
    overflow: hidden;
    transition: all 0.3s ease;
}

.faq-question {
    padding: 24px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 18px;
    transition: background 0.3s ease;
}

.faq-question:hover {
    background: #374151;
}

.faq-icon {
    font-size: 24px;
    transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding: 0 24px;
}

.faq-item.active .faq-answer {
    max-height: 200px;
    padding: 0 24px 24px;
}

/* Final CTA */
.final-cta {
    padding: 48px;
    text-align: center;
    background: #111827;
    border-top: 1px solid #374151;
}

.final-cta p {
    color: #9CA3AF;
    margin-bottom: 24px;
    font-size: 16px;
}

/* Footer */
footer {
    background: #111827;
    color: #9CA3AF;
    padding: 48px;
    font-size: 14px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    text-align: center;
}

/* Chevron Divider */
.chevron-divider {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px 0;
    background: transparent;
    position: relative;
}

.chevron-hero {
    position: absolute;
    top: calc(90vh - 60px); /* Position near bottom of viewport */
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    cursor: pointer;
    padding: 10px; /* Larger click area */
    transition: transform 0.3s ease;
}

.chevron-hero:hover {
    transform: translateX(-50%) scale(1.1);
}

.chevron-hero:focus {
    outline: none;
}

/* Section Chevron (at bottom of first feature section) */
.chevron-section {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    cursor: pointer;
    padding: 10px; /* Larger click area */
    transition: transform 0.3s ease;
}

.chevron-section:hover {
    transform: translateX(-50%) scale(1.1);
}

.chevron-section:focus {
    outline: none;
}


/* Material Symbols Chevron Icon */
.chevron-icon {
    font-size: 40px;
    line-height: 1;
    display: block;
    animation: bounce 2s infinite;
    color: #6B7280; /* Default gray color for section chevrons */
    user-select: none;
}

.chevron-hero .chevron-icon {
    color: rgba(255, 255, 255, 0.7); /* White for hero chevron */
}

.chevron-section .chevron-icon {
    color: #6B7280; /* Gray color for visibility */
}


@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(10px);
    }
    60% {
        transform: translateY(5px);
    }
}

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

@keyframes slide {
    0% {
        transform: translateX(0);
    }
    100% {
        transform: translateX(70px);
    }
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 36px;
    }
    
    .hero {
        min-height: 92vh; /* Smaller for mobile partial visibility */
        height: auto;
        padding-bottom: 60px; /* Space for chevron */
        /* Mobile image already loaded by default in mobile-first approach */
    }
    
    .chevron-hero {
        position: absolute; /* Keep absolute positioning */
        top: calc(85vh - 50px); /* Position based on viewport height */
        left: 50%;
        transform: translateX(-50%);
    }
    
    .feature-section {
        flex-direction: column !important;
        padding: 48px 24px;
    }
    
    .email-form {
        flex-direction: column;
    }
    
    .email-input {
        border-radius: 8px;
        border-right: 1px solid #E5E7EB;
        margin-bottom: 12px;
    }
    
    .cta-button {
        border-radius: 8px;
    }
    
    .phone-frame {
        width: 320px;
        height: 680px;
    }
    
    .desktop-frame {
        width: calc(100vw - 48px); /* Full width minus padding */
        max-width: none;
        height: 320px;
    }
    
    .tablet-frame {
        width: calc(100vw - 48px); /* Full width minus padding */
        max-width: none;
        height: calc((100vw - 48px) * 0.625); /* Maintain 16:10 aspect ratio */
        min-height: 250px;
    }
    
    .feature-visual {
        width: 100%;
        max-width: none;
    }
}

/* Small mobile devices */
@media (max-width: 480px) {
    .hero h1 {
        font-size: 28px;
    }
    
    .hero .subtitle {
        font-size: 18px;
    }
    
    .chevron-hero {
        top: calc(80vh - 45px); /* Adjust for smaller viewport */
    }
    
    .phone-frame {
        width: 280px;
        height: 600px;
    }
    
    .desktop-frame {
        height: 280px;
    }
    
    .tablet-frame {
        height: calc((100vw - 48px) * 0.625); /* Maintain aspect ratio */
        min-height: 200px;
    }
}

/* Tablets and larger mobile in landscape */
@media (min-width: 769px) and (max-width: 1024px) {
    .desktop-frame {
        width: 500px;
        height: 350px;
    }
    
    .tablet-frame {
        width: 480px;  /* Reduced from 640px */
        height: 300px;  /* Reduced from 400px */
    }
}

/* Form Submission Styles */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.success-message {
    color: #10b981;
    font-size: 0.95rem;
    margin-top: 1rem;
    padding: 0.75rem 1rem;
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: 8px;
    opacity: 0;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    display: none;
}

.success-message.show {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

.cta-button:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}