/* ========================================
   MAIN.CSS – Core Variables & Base Styles
   ======================================== */

:root {
    /* Deeper Purple Theme */
    --primary: #6D28D9;          /* deeper purple */
    --primary-dark: #4C1D95;
    --primary-light: #8B5CF6;
    --primary-gradient: linear-gradient(135deg, #6D28D9 0%, #7C3AED 50%, #EC4899 100%);

    --secondary: #EC4899;
    --secondary-dark: #BE185D;
    --secondary-light: #F472B6;

    --background: #FFFFFF;
    --background-secondary: #F8FAFC;
    --surface: #F1F5F9;

    --text: #0F172A;
    --text-secondary: #475569;
    --text-muted: #94A3B8;
    --text-inverse: #FFFFFF;

    --border: #E2E8F0;
    --border-light: #F1F5F9;
    --border-soft: rgba(15, 23, 42, 0.07);

    /* Glass surface tokens — used for the ambient background look */
    --glass-bg: rgba(255, 255, 255, 0.6);
    --glass-bg-strong: rgba(255, 255, 255, 0.78);
    --glass-border: rgba(255, 255, 255, 0.5);

    --shadow-sm: 0 2px 8px rgba(15,23,42,0.04);
    --shadow: 0 6px 18px rgba(15,23,42,0.06);
    --shadow-md: 0 10px 28px rgba(15,23,42,0.07);
    --shadow-lg: 0 18px 40px rgba(15,23,42,0.09);
    --shadow-xl: 0 28px 60px rgba(15,23,42,0.11);

    --radius-sm: 12px;
    --radius: 20px;
    --radius-lg: 28px;
    --radius-xl: 36px;
    --radius-pill: 999px;

    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);

    --font-xs: 0.75rem;
    --font-sm: 0.875rem;
    --font-base: 1rem;
    --font-lg: 1.125rem;
    --font-xl: 1.25rem;
    --font-2xl: 1.5rem;
    --font-3xl: 1.875rem;
    --font-4xl: 2.25rem;
    --font-5xl: 3rem;
    --font-6xl: 3.75rem;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--background);
    color: var(--text);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    position: relative;
    overflow-x: hidden;
}

/* 3D background canvas (Three.js) — sits behind everything, fixed to viewport */
#bg-3d {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    display: block;
    pointer-events: none;
}

/* Ambient gradient-mesh background, sits behind every section on every page.
   Now layered just above the 3D canvas as a soft brand-colored wash. */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background-image:
        radial-gradient(ellipse 60% 50% at 12% 8%, rgba(109, 40, 217, 0.07), transparent 60%),
        radial-gradient(ellipse 55% 45% at 90% 12%, rgba(236, 72, 153, 0.06), transparent 60%),
        radial-gradient(ellipse 60% 55% at 50% 95%, rgba(139, 92, 246, 0.06), transparent 60%);
    transition: opacity 0.3s;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Typography - more refined */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 0.5rem;
    color: var(--text);
}
h1 { font-size: var(--font-5xl); letter-spacing: -0.02em; }
h2 { font-size: var(--font-4xl); letter-spacing: -0.01em; }
h3 { font-size: var(--font-3xl); }
h4 { font-size: var(--font-2xl); }
p { margin-bottom: 1rem; color: var(--text-secondary); }

a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }

/* Buttons - refined */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.7rem 1.6rem;
    border-radius: var(--radius-pill);
    font-weight: 600;
    font-size: var(--font-base);
    cursor: pointer;
    transition: var(--transition);
    border: none;
    text-align: center;
    line-height: 1.4;
    justify-content: center;
}
.btn i { font-size: 1.1em; }
.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 6px 16px rgba(109, 40, 217, 0.25);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 24px rgba(109, 40, 217, 0.32);
    color: white;
}
.btn-secondary {
    background: var(--secondary);
    color: white;
    box-shadow: 0 6px 16px rgba(236, 72, 153, 0.25);
}
.btn-secondary:hover {
    background: var(--secondary-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 24px rgba(236, 72, 153, 0.32);
    color: white;
}
.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 1.5px solid var(--primary);
}
.btn-outline:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}
.btn-light {
    background: white;
    color: var(--primary);
}
.btn-light:hover {
    background: rgba(255,255,255,0.9);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    color: var(--primary-dark);
}
.btn-large { padding: 0.9rem 2.25rem; font-size: var(--font-lg); }
.btn-sm { padding: 0.45rem 1.15rem; font-size: var(--font-sm); }

/* Cards */
.card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: var(--transition);
    border: 1px solid var(--border-soft);
    box-shadow: var(--shadow-sm);
}
.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
    border-color: var(--primary-light);
}

/* Grid */
.grid {
    display: grid;
    gap: 1.5rem;
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Section Headers */
.section-header {
    margin-bottom: 3rem;
}
.section-title {
    font-size: var(--font-4xl);
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline-block;
}
.section-subtitle {
    font-size: var(--font-xl);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Utilities */
.text-center { text-align: center; }
.gradient-text {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.mt-5 { margin-top: 3rem; }
.mt-4 { margin-top: 2rem; }
.mb-4 { margin-bottom: 2rem; }

/* Responsive */
@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    h1 { font-size: var(--font-4xl); }
    h2 { font-size: var(--font-3xl); }
    .section-title { font-size: var(--font-3xl); }
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .container { padding: 0 1rem; }
    .btn-large { padding: 0.75rem 1.5rem; font-size: var(--font-base); }
}
@media (max-width: 480px) {
    h1 { font-size: var(--font-3xl); }
    .card { padding: 1rem; }
}