/* ==========================================================================
   Closo Landing Page - Modern Styles
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Variables
   -------------------------------------------------------------------------- */
:root {
    /* Colors */
    --color-primary: #6366f1;
    --color-primary-dark: #4f46e5;
    --color-primary-light: #818cf8;
    --color-secondary: #1e1b4b;
    --color-accent: #a78bfa;

    --color-white: #ffffff;
    --color-gray-50: #fafafa;
    --color-gray-100: #f4f4f5;
    --color-gray-200: #e4e4e7;
    --color-gray-300: #d4d4d8;
    --color-gray-400: #a1a1aa;
    --color-gray-500: #71717a;
    --color-gray-600: #52525b;
    --color-gray-700: #3f3f46;
    --color-gray-800: #27272a;
    --color-gray-900: #18181b;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;

    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-2xl: 2rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 25px -5px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 40px -10px rgb(0 0 0 / 0.15);
    --shadow-glow: 0 0 60px -15px var(--color-primary);

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-gray-600);
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
}

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

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

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

ul, ol {
    list-style: none;
}

/* --------------------------------------------------------------------------
   Layout
   -------------------------------------------------------------------------- */
.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.section {
    padding: var(--spacing-4xl) 0;
}

.section-header {
    margin-bottom: var(--spacing-3xl);
}

.section-header.center {
    text-align: center;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--color-gray-900);
    line-height: 1.2;
    letter-spacing: -0.02em;
}

/* --------------------------------------------------------------------------
   Navigation
   -------------------------------------------------------------------------- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
    padding: 0 var(--spacing-lg);
    max-width: 1100px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-gray-900);
}

.logo-img {
    width: 28px;
    height: 28px;
    object-fit: contain;
}

.logo-img-lg {
    width: 32px;
    height: 32px;
}

.logo-img-shadow {
    filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.15));
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    font-size: 0.9rem;
    font-weight: 600;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-full);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: var(--color-white);
    box-shadow: 0 4px 15px -3px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px -5px rgba(99, 102, 241, 0.5);
}

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

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1rem;
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: calc(72px + var(--spacing-3xl)) var(--spacing-lg) var(--spacing-3xl);
    background: var(--color-gray-50);
    position: relative;
    overflow: hidden;
}

/* Gradient orbs background */
.hero::before {
    content: '';
    position: absolute;
    top: -20%;
    right: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(167, 139, 250, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 700px;
    text-align: center;
}

.hero h1 {
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 800;
    color: var(--color-gray-900);
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: var(--spacing-lg);
}

.hero h1 .highlight {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--color-gray-500);
    max-width: 550px;
    margin: 0 auto var(--spacing-xl);
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
}

.hero-hint {
    font-size: 0.875rem;
    color: var(--color-gray-400);
}

/* --------------------------------------------------------------------------
   Features Section
   -------------------------------------------------------------------------- */
.features {
    background: var(--color-white);
}

.features-grid {
    display: grid;
    gap: var(--spacing-lg);
    grid-template-columns: 1fr;
}

.feature-card {
    background: var(--color-gray-50);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
    border: 1px solid transparent;
}

.feature-card:hover {
    background: var(--color-white);
    border-color: var(--color-gray-100);
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    margin-bottom: var(--spacing-lg);
    box-shadow: 0 8px 20px -5px rgba(99, 102, 241, 0.3);
}

.feature-card h3 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    font-size: 0.95rem;
    color: var(--color-gray-500);
    line-height: 1.6;
}

/* --------------------------------------------------------------------------
   Use Cases Section
   -------------------------------------------------------------------------- */
.usages {
    background: var(--color-gray-50);
}

.usages-grid {
    display: grid;
    gap: var(--spacing-md);
    grid-template-columns: repeat(2, 1fr);
}

.usage-card {
    background: var(--color-white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    text-align: center;
    transition: all var(--transition-base);
    border: 1px solid var(--color-gray-100);
}

.usage-card:hover {
    border-color: var(--color-primary-light);
    box-shadow: var(--shadow-lg), 0 0 0 1px var(--color-primary-light);
    transform: translateY(-4px);
}

.usage-emoji {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    display: block;
}

.usage-card h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-xs);
}

.usage-card p {
    font-size: 0.875rem;
    color: var(--color-gray-500);
    line-height: 1.5;
    display: none;
}

/* --------------------------------------------------------------------------
   Quote / CTA Section
   -------------------------------------------------------------------------- */
.quote {
    background: linear-gradient(135deg, var(--color-secondary) 0%, #312e81 100%);
    padding: var(--spacing-4xl) 0;
    position: relative;
    overflow: hidden;
}

.quote::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.2) 0%, transparent 70%);
    border-radius: 50%;
}

.quote-content {
    position: relative;
    z-index: 1;
}

.quote-content p {
    font-size: clamp(1.25rem, 3vw, 1.75rem);
    color: var(--color-gray-300);
    line-height: 1.5;
}

.quote-content strong {
    color: var(--color-white);
}

.quote .btn-primary {
    background: var(--color-white);
    color: var(--color-primary);
    box-shadow: 0 4px 15px -3px rgba(0, 0, 0, 0.2);
}

.quote .btn-primary:hover {
    background: var(--color-gray-50);
    box-shadow: 0 8px 25px -5px rgba(0, 0, 0, 0.3);
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
    background: var(--color-gray-900);
    color: var(--color-gray-400);
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-brand .logo {
    color: var(--color-white);
    margin-bottom: var(--spacing-md);
}

.footer-brand p {
    font-size: 0.9rem;
    color: var(--color-gray-500);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-xl);
}

.footer-col h4 {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-white);
    margin-bottom: var(--spacing-md);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-col a {
    display: block;
    font-size: 0.9rem;
    color: var(--color-gray-400);
    margin-bottom: var(--spacing-sm);
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--color-gray-800);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.85rem;
    color: var(--color-gray-500);
}

/* --------------------------------------------------------------------------
   Animations
   -------------------------------------------------------------------------- */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeIn 0.8s ease forwards;
}

.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
}

.fade-in-up.visible {
    animation: fadeInUp 0.6s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* --------------------------------------------------------------------------
   Tablet Styles (min-width: 640px)
   -------------------------------------------------------------------------- */
@media (min-width: 640px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .usage-card p {
        display: block;
    }
}

/* --------------------------------------------------------------------------
   Desktop Styles (min-width: 1024px)
   -------------------------------------------------------------------------- */
@media (min-width: 1024px) {
    .hero-content {
        max-width: 800px;
    }

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

    .usages-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-lg);
    }

    .footer-content {
        flex-direction: row;
        justify-content: space-between;
    }

    .footer-brand {
        max-width: 280px;
    }

    .footer-links {
        gap: var(--spacing-3xl);
    }
}

/* --------------------------------------------------------------------------
   Reduced Motion
   -------------------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}