/* ==========================================================================
   Design System — andrzejbula.eu
   Foundation: custom properties, reset, typography, utilities, buttons,
   scroll animations, responsive overrides.
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. CSS Custom Properties
   -------------------------------------------------------------------------- */

:root {
    /* Colors */
    --color-dark: #1a1a2e;
    --color-dark-light: #2d2d44;
    --color-dark-footer: #141425;
    --color-white: #ffffff;
    --color-off-white: #f5f5f0;
    --color-gold: #c9a84c;
    --color-gold-light: #d4b86a;
    --color-text: #333333;
    --color-text-muted: #6b6b7b;

    /* Typography */
    --font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-size-base: 17px;
    --font-size-small: 15px;
    --font-size-label: 13px;
    --font-size-h1: 64px;
    --font-size-h2: 40px;
    --font-size-h3: 24px;
    --line-height-base: 1.7;
    --line-height-heading: 1.1;

    /* Spacing (8px base scale) */
    --space-xs: 8px;
    --space-sm: 16px;
    --space-md: 24px;
    --space-lg: 32px;
    --space-xl: 48px;
    --space-2xl: 64px;
    --space-3xl: 96px;
    --space-4xl: 128px;

    /* Layout */
    --max-width: 1200px;
    --reading-width: 800px;
    --border-radius: 8px;
    --mobile-padding: 24px;

    /* Transitions */
    --transition-fast: 200ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 400ms ease;
}

/* --------------------------------------------------------------------------
   2. Reset / Base Styles
   -------------------------------------------------------------------------- */

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

body {
    margin: 0;
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-text);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3 {
    margin-top: 0;
    line-height: var(--line-height-heading);
}

h1 {
    font-size: var(--font-size-h1);
    font-weight: 800;
    letter-spacing: -0.02em;
}

h2 {
    font-size: var(--font-size-h2);
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.01em;
}

h3 {
    font-size: var(--font-size-h3);
    font-weight: 600;
    line-height: 1.3;
    letter-spacing: 0;
}

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

a:hover {
    color: var(--color-gold-light);
}

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

/* --------------------------------------------------------------------------
   3. Utility Classes
   -------------------------------------------------------------------------- */

/* Layout containers */

.container {
    max-width: var(--max-width);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--mobile-padding);
    padding-right: var(--mobile-padding);
}

.container--narrow {
    max-width: var(--reading-width);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--mobile-padding);
    padding-right: var(--mobile-padding);
}

/* Section label — gold uppercase with preceding dash */

.section-label {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: var(--color-gold);
    font-size: var(--font-size-label);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    line-height: 1.4;
    margin-bottom: var(--space-sm);
}

.section-label::before {
    content: '';
    display: inline-block;
    width: 24px;
    height: 2px;
    background-color: var(--color-gold);
    flex-shrink: 0;
}

/* Section padding */

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

/* Background colors */

.bg-white {
    background-color: var(--color-white);
}

.bg-off-white {
    background-color: var(--color-off-white);
}

.bg-dark {
    background-color: var(--color-dark);
}

.bg-dark-footer {
    background-color: var(--color-dark-footer);
}

/* Text colors */

.text-white {
    color: var(--color-white);
}

.text-gold {
    color: var(--color-gold);
}

.text-muted {
    color: var(--color-text-muted);
}

/* --------------------------------------------------------------------------
   4. Buttons
   -------------------------------------------------------------------------- */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border: 2px solid transparent;
    border-radius: var(--border-radius);
    font-family: var(--font-family);
    font-size: var(--font-size-small);
    font-weight: 600;
    line-height: 1.4;
    cursor: pointer;
    transition:
        background-color var(--transition-fast),
        color var(--transition-fast),
        border-color var(--transition-fast),
        transform var(--transition-fast);
    text-decoration: none;
}

.btn:hover {
    transform: scale(1.02);
}

.btn:active {
    transform: scale(0.98);
}

/* Gold filled button */

.btn--gold {
    background-color: var(--color-gold);
    color: var(--color-white);
    border-color: var(--color-gold);
}

.btn--gold:hover {
    background-color: var(--color-gold-light);
    border-color: var(--color-gold-light);
    color: var(--color-white);
}

/* Outline button */

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

.btn--outline:hover {
    background-color: var(--color-gold);
    color: var(--color-white);
    border-color: var(--color-gold);
}

/* --------------------------------------------------------------------------
   5. Scroll-Triggered Fade-In
   -------------------------------------------------------------------------- */

.fade-in {
    opacity: 0;
    transform: translateY(16px);
    transition:
        opacity var(--transition-slow),
        transform var(--transition-slow);
}

.fade-in.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* --------------------------------------------------------------------------
   6. Reduced Motion
   -------------------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .fade-in {
        opacity: 1;
        transform: none;
    }
}

/* --------------------------------------------------------------------------
   7. Responsive Typography
   -------------------------------------------------------------------------- */

/* Tablet — below 1200px */

@media (max-width: 1199px) {
    h1 {
        font-size: 48px;
    }
}

/* Mobile — below 768px */

@media (max-width: 767px) {
    h1 {
        font-size: 36px;
    }

    h2 {
        font-size: 32px;
    }

    .section-padding {
        padding-top: var(--space-2xl);
        padding-bottom: var(--space-2xl);
    }
}