/* ==============================================
   SYNAPTIK - GRADIENT DESIGN SYSTEM
   ============================================== */

/* ========== VARIABLES ========== */
:root {
    /* Gradients principaux */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --gradient-secondary: linear-gradient(135deg, #4facfe 0%, #00f2fe 50%, #43e97b 100%);
    --gradient-accent: linear-gradient(135deg, #fa709a 0%, #fee140 50%, #30cfd0 100%);
    --gradient-success: linear-gradient(135deg, #56ab2f 0%, #a8e063 50%, #38ef7d 100%);
    --gradient-warning: linear-gradient(135deg, #f857a6 0%, #ff5858 100%);
    --gradient-info: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);

    /* Gradients overlay */
    --gradient-overlay-dark: linear-gradient(135deg, rgba(102, 126, 234, 0.9) 0%, rgba(118, 75, 162, 0.9) 100%);
    --gradient-overlay-light: linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, rgba(255, 255, 255, 0.85) 100%);

    /* Couleurs solides */
    --color-bg-light: #f8f9ff;
    --color-bg-dark: #1a1a2e;
    --color-text-primary: #2d3748;
    --color-text-secondary: #718096;
    --color-white: #ffffff;
    --color-black: #000000;

    /* Glass morphism */
    --glass-bg: rgba(255, 255, 255, 0.1);
    --glass-border: rgba(255, 255, 255, 0.2);
    --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);

    /* Typographie */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Poppins', sans-serif;
    --font-accent: 'Montserrat', sans-serif;

    /* Spacing */
    --space-xs: 0.5rem;    /* 8px */
    --space-sm: 1rem;      /* 16px */
    --space-md: 1.5rem;    /* 24px */
    --space-lg: 2rem;      /* 32px */
    --space-xl: 3rem;      /* 48px */
    --space-2xl: 4rem;     /* 64px */
    --space-3xl: 6rem;     /* 96px */

    /* Border radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* Shadows gradient */
    --shadow-primary: 0 10px 40px rgba(102, 126, 234, 0.3);
    --shadow-secondary: 0 10px 40px rgba(79, 172, 254, 0.3);
    --shadow-accent: 0 10px 40px rgba(250, 112, 154, 0.3);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.15);

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* ========== BASE STYLES ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background: var(--color-bg-light);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

.gradient-body {
    position: relative;
}

.gradient-body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(240, 147, 251, 0.05) 100%);
    pointer-events: none;
    z-index: -1;
}

/* ========== TYPOGRAPHY ========== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-md);
}

h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
}

h2 {
    font-size: clamp(2rem, 4vw, 3rem);
}

h3 {
    font-size: clamp(1.5rem, 3vw, 2rem);
}

h4 {
    font-size: clamp(1.25rem, 2.5vw, 1.5rem);
}

h5 {
    font-size: clamp(1.125rem, 2vw, 1.25rem);
}

h6 {
    font-size: 1rem;
}

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

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

/* ========== CONTAINER & LAYOUT ========== */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.container-fluid {
    width: 100%;
    padding: 0 var(--space-lg);
}

.section {
    padding: var(--space-3xl) 0;
}

.section-sm {
    padding: var(--space-2xl) 0;
}

.section-lg {
    padding: calc(var(--space-3xl) * 1.5) 0;
}

/* ========== GRADIENT UTILITIES ========== */
.gradient-bg-primary {
    background: var(--gradient-primary);
}

.gradient-bg-secondary {
    background: var(--gradient-secondary);
}

.gradient-bg-accent {
    background: var(--gradient-accent);
}

.gradient-bg-success {
    background: var(--gradient-success);
}

.gradient-text-primary {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.gradient-text-secondary {
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.gradient-text-accent {
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ========== GLASS MORPHISM ========== */
.glass-effect {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: var(--glass-shadow);
    border-radius: var(--radius-lg);
}

.glass-effect-dark {
    background: rgba(26, 26, 46, 0.7);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* ========== BUTTONS ========== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-lg);
    border: none;
    border-radius: var(--radius-full);
    font-family: var(--font-primary);
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

.btn-gradient-primary {
    background: var(--gradient-primary);
    background-size: 200% 200%;
    color: var(--color-white);
    box-shadow: var(--shadow-primary);
}

.btn-gradient-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 50px rgba(102, 126, 234, 0.4);
    background-position: right center;
}

.btn-gradient-secondary {
    background: var(--gradient-secondary);
    background-size: 200% 200%;
    color: var(--color-white);
    box-shadow: var(--shadow-secondary);
}

.btn-gradient-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 50px rgba(79, 172, 254, 0.4);
    background-position: right center;
}

.btn-gradient-accent {
    background: var(--gradient-accent);
    background-size: 200% 200%;
    color: var(--color-white);
    box-shadow: var(--shadow-accent);
}

.btn-gradient-accent:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 50px rgba(250, 112, 154, 0.4);
    background-position: right center;
}

.btn-gradient-success {
    background: var(--gradient-success);
    background-size: 200% 200%;
    color: var(--color-white);
    box-shadow: 0 10px 40px rgba(86, 171, 47, 0.3);
}

.btn-gradient-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 50px rgba(86, 171, 47, 0.4);
    background-position: right center;
}

.btn-outline {
    background: transparent;
    color: var(--color-text-primary);
    border: 2px solid transparent;
    background-image: linear-gradient(white, white), var(--gradient-primary);
    background-origin: border-box;
    background-clip: padding-box, border-box;
}

.btn-outline:hover {
    background-image: var(--gradient-primary), var(--gradient-primary);
    color: var(--color-white);
    transform: translateY(-2px);
}

.btn-block {
    width: 100%;
    display: flex;
}

/* ========== ANIMATIONS ========== */
@keyframes gradient-shift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

.gradient-animated {
    background-size: 200% 200%;
    animation: gradient-shift 3s ease infinite;
}

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

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

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

.float-animation {
    animation: float 3s ease-in-out infinite;
}

/* ========== SCROLL TO TOP ========== */
.scroll-to-top {
    position: fixed;
    bottom: var(--space-lg);
    right: var(--space-lg);
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border: none;
    border-radius: 50%;
    color: var(--color-white);
    font-size: 1.25rem;
    cursor: pointer;
    box-shadow: var(--shadow-primary);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    z-index: 1000;
}

.scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 50px rgba(102, 126, 234, 0.4);
}

/* ========== UTILITY CLASSES ========== */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--space-xs); }
.mb-2 { margin-bottom: var(--space-sm); }
.mb-3 { margin-bottom: var(--space-md); }
.mb-4 { margin-bottom: var(--space-lg); }
.mb-5 { margin-bottom: var(--space-xl); }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--space-xs); }
.mt-2 { margin-top: var(--space-sm); }
.mt-3 { margin-top: var(--space-md); }
.mt-4 { margin-top: var(--space-lg); }
.mt-5 { margin-top: var(--space-xl); }

.required {
    color: #f857a6;
    font-weight: bold;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 768px) {
    :root {
        --space-3xl: 4rem;
        --space-2xl: 3rem;
    }

    .container {
        padding: 0 var(--space-md);
    }

    .scroll-to-top {
        bottom: var(--space-md);
        right: var(--space-md);
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
}