/* ====================================
   LicitFlow - Tech Premium Dark Theme
   ==================================== */

/* CSS Variables - Design Tokens */
:root {
    /* Colors - HSL Format */
    --background: 222 47% 4%;
    --foreground: 210 40% 98%;
    
    --card: 222 47% 7%;
    --card-foreground: 210 40% 98%;
    
    --primary: 187 95% 45%;
    --primary-foreground: 222 47% 4%;
    
    --secondary: 215 25% 12%;
    --secondary-foreground: 210 40% 90%;
    
    --muted: 215 25% 15%;
    --muted-foreground: 215 20% 55%;
    
    --accent: 250 60% 50%;
    --accent-foreground: 210 40% 98%;
    
    --destructive: 0 72% 51%;
    --success: 142 80% 45%;
    --warning: 38 95% 55%;
    --info: 187 95% 50%;
    
    --border: 215 25% 15%;
    --ring: 187 95% 45%;
    
    --radius: 0.75rem;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, hsl(187, 95%, 45%) 0%, hsl(250, 80%, 60%) 100%);
    --gradient-hero: linear-gradient(135deg, hsl(222, 47%, 6%) 0%, hsl(250, 60%, 15%) 50%, hsl(187, 40%, 15%) 100%);
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 hsl(0 0% 0% / 0.3);
    --shadow-md: 0 4px 6px -1px hsl(0 0% 0% / 0.4), 0 2px 4px -2px hsl(0 0% 0% / 0.3);
    --shadow-lg: 0 10px 15px -3px hsl(0 0% 0% / 0.5), 0 4px 6px -4px hsl(0 0% 0% / 0.4);
    --shadow-glow: 0 0 30px hsl(187 95% 45% / 0.15);
}

/* Reset & Base Styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: 
        radial-gradient(ellipse at 0% 0%, hsl(187 95% 45% / 0.06) 0%, transparent 50%),
        radial-gradient(ellipse at 100% 100%, hsl(250 80% 60% / 0.06) 0%, transparent 50%),
        hsl(var(--background));
    color: hsl(var(--foreground));
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 300;
    letter-spacing: -0.025em;
    color: hsl(210 40% 98%);
}

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
    height: auto;
}

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ====================================
   HEADER
   ==================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 50;
    background: hsl(var(--background) / 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid hsl(var(--border));
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0.5rem;
    background: var(--gradient-primary);
    color: hsl(var(--primary-foreground));
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    color: hsl(var(--foreground));
}

.nav-buttons {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* ====================================
   BUTTONS
   ==================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--radius);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}

.btn-primary {
    background: hsl(var(--primary));
    color: hsl(var(--primary-foreground));
    border-color: hsl(var(--primary));
}

.btn-primary:hover {
    background: hsl(187 95% 40%);
    box-shadow: var(--shadow-glow);
}

.btn-outline {
    background: transparent;
    color: hsl(var(--foreground));
    border-color: hsl(var(--border));
}

.btn-outline:hover {
    background: hsl(var(--secondary));
    border-color: hsl(var(--muted-foreground) / 0.3);
}

.btn-ghost {
    background: transparent;
    color: hsl(var(--muted-foreground));
}

.btn-ghost:hover {
    background: hsl(var(--secondary));
    color: hsl(var(--foreground));
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
}

/* ====================================
   HERO SECTION
   ==================================== */
.hero {
    padding-top: 8rem;
    padding-bottom: 5rem;
}

.hero-content {
    text-align: center;
    max-width: 56rem;
    margin: 0 auto;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

@media (min-width: 768px) {
    .hero-title {
        font-size: 3.75rem;
    }
}

.text-primary {
    color: hsl(var(--primary));
}

.hero-description {
    font-size: 1.25rem;
    color: hsl(var(--muted-foreground));
    max-width: 42rem;
    margin: 0 auto 2rem;
}

.hero-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    justify-content: center;
}

@media (min-width: 640px) {
    .hero-buttons {
        flex-direction: row;
    }
}

/* ====================================
   FEATURES SECTION
   ==================================== */
.features {
    padding: 5rem 0;
    background: hsl(var(--muted) / 0.3);
}

.features-title {
    font-size: 1.875rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

@media (min-width: 768px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.feature-card {
    background: hsl(var(--card));
    padding: 2rem;
    border-radius: var(--radius);
    border: 1px solid hsl(var(--border));
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.feature-card:hover {
    border-color: hsl(187 95% 45% / 0.4);
    box-shadow: var(--shadow-lg), 0 0 30px hsl(187 95% 45% / 0.1);
    transform: translateY(-2px);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 3rem;
    height: 3rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
}

.feature-icon-primary {
    background: hsl(var(--primary) / 0.1);
    color: hsl(var(--primary));
}

.feature-icon-warning {
    background: hsl(var(--warning) / 0.1);
    color: hsl(var(--warning));
}

.feature-icon-success {
    background: hsl(var(--success) / 0.1);
    color: hsl(var(--success));
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.feature-description {
    color: hsl(var(--muted-foreground));
}

/* ====================================
   CTA SECTION
   ==================================== */
.cta {
    padding: 5rem 0;
}

.cta-content {
    text-align: center;
    max-width: 48rem;
    margin: 0 auto;
}

.cta-title {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.cta-description {
    color: hsl(var(--muted-foreground));
    margin-bottom: 2rem;
}

/* ====================================
   FOOTER
   ==================================== */
.footer {
    padding: 2rem 0;
    border-top: 1px solid hsl(var(--border));
    text-align: center;
    color: hsl(var(--muted-foreground));
    font-size: 0.875rem;
}

/* ====================================
   ANIMATIONS
   ==================================== */
@keyframes fade-in {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fade-in 0.5s ease-out forwards;
}

/* Staggered animation for feature cards */
.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }

/* ====================================
   UTILITY CLASSES
   ==================================== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}