/* ============================================
   STK AI Venture Builder - Design System
   Dark Mode First | Data-Driven Aesthetic
   ============================================ */

:root {
    /* === COLOR PALETTE === */
    /* Base - Dark Tech */
    --color-obsidian: #050505;
    --color-midnight: #0a0f1c;
    --color-deep-space: #0d1117;
    --color-slate: #161b22;

    /* STK Brand - Deep Blue */
    --color-stk-blue: #084888;
    --color-stk-blue-light: #0a5aa8;
    --color-stk-blue-dark: #063666;

    /* Accents for Data/AI Context */
    --color-cyan-bright: #00d9ff;
    --color-purple-electric: #bc13fe;

    /* Neutrals */
    --color-text-primary: #e6edf3;
    --color-text-secondary: #8d96a0;
    --color-text-tertiary: #575e66;
    --color-border: rgba(255, 255, 255, 0.08);
    --color-border-bright: rgba(8, 72, 136, 0.3);

    /* === TYPOGRAPHY === */
    --font-display: 'Exo 2', sans-serif;
    --font-body: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Courier New', monospace;

    /* Font Sizes - Fluid Scale */
    --text-xs: 0.75rem;
    /* 12px */
    --text-sm: 0.875rem;
    /* 14px */
    --text-base: 1rem;
    /* 16px */
    --text-lg: 1.125rem;
    /* 18px */
    --text-xl: 1.25rem;
    /* 20px */
    --text-2xl: 1.5rem;
    /* 24px */
    --text-3xl: 1.875rem;
    /* 30px */
    --text-4xl: 2.25rem;
    /* 36px */
    --text-5xl: 3rem;
    /* 48px */
    --text-6xl: 3.75rem;
    /* 60px */

    /* Line Heights */
    --leading-tight: 1.2;
    --leading-normal: 1.5;
    --leading-relaxed: 1.75;

    /* === SPACING === */
    --space-1: 0.25rem;
    /* 4px */
    --space-2: 0.5rem;
    /* 8px */
    --space-3: 0.75rem;
    /* 12px */
    --space-4: 1rem;
    /* 16px */
    --space-5: 1.5rem;
    /* 24px */
    --space-6: 2rem;
    /* 32px */
    --space-8: 3rem;
    /* 48px */
    --space-10: 4rem;
    /* 64px */
    --space-12: 6rem;
    /* 96px */
    --space-16: 8rem;
    /* 128px */

    /* === GLASSMORPHISM === */
    --glass-bg: rgba(22, 27, 34, 0.6);
    --glass-bg-heavy: rgba(22, 27, 34, 0.85);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-blur: 20px;
    --glass-blur-heavy: 40px;

    /* === SHADOWS & GLOWS === */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.6);

    --glow-blue: 0 0 20px rgba(8, 72, 136, 0.4);
    --glow-blue-strong: 0 0 40px rgba(8, 72, 136, 0.6), 0 0 80px rgba(8, 72, 136, 0.3);
    --glow-cyan: 0 0 20px rgba(0, 217, 255, 0.3);

    /* === TRANSITIONS === */
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

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

    /* === GRADIENTS === */
    --gradient-mesh:
        radial-gradient(at 0% 0%, rgba(8, 72, 136, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(188, 19, 254, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(0, 217, 255, 0.08) 0px, transparent 50%),
        radial-gradient(at 0% 100%, rgba(8, 72, 136, 0.12) 0px, transparent 50%);

    --gradient-blue: linear-gradient(135deg, var(--color-stk-blue) 0%, var(--color-stk-blue-dark) 100%);
    --gradient-blue-bright: linear-gradient(135deg, var(--color-stk-blue-light) 0%, var(--color-stk-blue) 100%);
    --gradient-border: linear-gradient(135deg, rgba(8, 72, 136, 0.5), rgba(0, 217, 255, 0.3));
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-body);
    font-size: var(--text-base);
    line-height: var(--leading-normal);
    color: var(--color-text-primary);
    background-color: var(--color-obsidian);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    /* Prevent horizontal scroll on mobile */
}

/* Animated mesh gradient background */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -2;
    background: var(--gradient-mesh);
    animation: mesh-flow 15s ease-in-out infinite;
}

/* Subtle grid pattern overlay */
body::after {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -1;
    background-image:
        linear-gradient(var(--color-border) 1px, transparent 1px),
        linear-gradient(90deg, var(--color-border) 1px, transparent 1px);
    background-size: 40px 40px;
    opacity: 0.3;
    animation: grid-flow 20s linear infinite;
}

@keyframes mesh-flow {
    0% {
        background-position: 0% 0%, 100% 0%, 50% 100%, 100% 100%;
    }

    25% {
        background-position: 100% 25%, 75% 50%, 25% 75%, 50% 25%;
    }

    50% {
        background-position: 50% 50%, 0% 100%, 100% 50%, 0% 50%;
    }

    75% {
        background-position: 25% 75%, 50% 25%, 75% 25%, 100% 75%;
    }

    100% {
        background-position: 0% 100%, 100% 0%, 50% 100%, 100% 100%;
    }
}

@keyframes grid-flow {
    from {
        background-position: 0 0;
    }

    to {
        background-position: 40px 40px;
    }
}

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: var(--leading-tight);
    color: var(--color-text-primary);
}

h1 {
    font-size: var(--text-6xl);
}

h2 {
    font-size: var(--text-4xl);
}

h3 {
    font-size: var(--text-2xl);
}

h4 {
    font-size: var(--text-xl);
}

p {
    color: var(--color-text-secondary);
    line-height: var(--leading-relaxed);
}

.text-mono {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    letter-spacing: -0.02em;
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.container {
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

.section {
    padding-top: var(--space-16);
    padding-bottom: var(--space-16);
}

/* Glassmorphism Card */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition-smooth);
}

.glass-card:hover {
    background: var(--glass-bg-heavy);
    border-color: rgba(8, 72, 136, 0.5);
    box-shadow: var(--glow-blue);
    /* Removed transform: translateY(-4px) to prevent border clipping */
}

/* Gradient Border Effect */
.gradient-border {
    position: relative;
    background: var(--glass-bg);
    border-radius: var(--radius-lg);
}

.gradient-border::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    padding: 1px;
    background: var(--gradient-border);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    pointer-events: none;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-4) var(--space-6);
    font-family: var(--font-body);
    font-size: var(--text-base);
    font-weight: 600;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-smooth);
}

.btn-primary {
    background: var(--gradient-blue-bright);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    box-shadow: var(--glow-blue-strong);
    transform: translateY(-2px);
}

.btn-ghost {
    background: transparent;
    border: 1px solid var(--color-border-bright);
    color: var(--color-text-primary);
}

.btn-ghost:hover {
    background: rgba(8, 72, 136, 0.1);
    border-color: var(--color-stk-blue);
}

/* Ripple Effect for Mobile */
.ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.4);
    width: 20px;
    height: 20px;
    transform: translate(-50%, -50%);
    pointer-events: none;
    animation: ripple-animation 0.6s ease-out;
}

@keyframes ripple-animation {
    from {
        transform: translate(-50%, -50%) scale(0);
        opacity: 1;
    }

    to {
        transform: translate(-50%, -50%) scale(15);
        opacity: 0;
    }
}

/* Tags/Pills */
.tag {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 500;
    color: var(--color-cyan-bright);
    background: rgba(0, 217, 255, 0.1);
    border: 1px solid rgba(0, 217, 255, 0.2);
    border-radius: var(--radius-full);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* ============================================
   ANIMATIONS
   ============================================ */

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

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

@keyframes glow-pulse {

    0%,
    100% {
        box-shadow: var(--glow-blue);
    }

    50% {
        box-shadow: var(--glow-blue-strong);
    }
}

.fade-in-up {
    opacity: 0;
    animation: fadeInUp 0.8s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* Stagger animation delays for sequential elements */
.fade-in-up:nth-child(1) {
    animation-delay: 0.1s;
}

.fade-in-up:nth-child(2) {
    animation-delay: 0.2s;
}

.fade-in-up:nth-child(3) {
    animation-delay: 0.3s;
}

.fade-in-up:nth-child(4) {
    animation-delay: 0.4s;
}

.fade-in-up:nth-child(5) {
    animation-delay: 0.5s;
}

.fade-in-up:nth-child(6) {
    animation-delay: 0.6s;
}

/* ============================================
   RESPONSIVE TYPOGRAPHY
   ============================================ */

@media (max-width: 768px) {
    :root {
        --text-6xl: 2.5rem;
        /* 40px */
        --text-5xl: 2rem;
        /* 32px */
        --text-4xl: 1.75rem;
        /* 28px */
    }

    .container {
        padding-left: var(--space-4);
        padding-right: var(--space-4);
    }

    .section {
        padding-top: var(--space-10);
        padding-bottom: var(--space-10);
    }
}