/* ============================================================
   BSF DESIGN SYSTEM — BASE
   Premium dark theme with gold accents
   ============================================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Outfit:wght@300;400;500;600;700;800;900&display=swap');

/* --- Design Tokens --- */
:root {
    /* Colors */
    --color-bg-primary: #050505;
    --color-bg-secondary: #0a0a0a;
    --color-bg-tertiary: #111111;
    --color-bg-card: #141414;
    --color-bg-card-hover: #1a1a1a;
    --color-bg-elevated: #1e1e1e;

    --color-gold: #c9a84c;
    --color-gold-light: #dfc06a;
    --color-gold-dark: #a08535;
    --color-gold-muted: rgba(201, 168, 76, 0.15);
    --color-gold-glow: rgba(201, 168, 76, 0.3);

    --color-white: #ffffff;
    --color-white-90: rgba(255, 255, 255, 0.9);
    --color-white-70: rgba(255, 255, 255, 0.7);
    --color-white-50: rgba(255, 255, 255, 0.5);
    --color-white-30: rgba(255, 255, 255, 0.3);
    --color-white-10: rgba(255, 255, 255, 0.1);
    --color-white-05: rgba(255, 255, 255, 0.05);

    --color-success: #22c55e;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-info: #3b82f6;

    /* Glass */
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-bg-hover: rgba(255, 255, 255, 0.06);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-border-hover: rgba(201, 168, 76, 0.3);

    /* Typography */
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;

    --fs-display: clamp(3rem, 6vw, 5.5rem);
    --fs-h1: clamp(2.2rem, 4vw, 3.5rem);
    --fs-h2: clamp(1.8rem, 3vw, 2.8rem);
    --fs-h3: clamp(1.3rem, 2vw, 1.75rem);
    --fs-h4: clamp(1.1rem, 1.5vw, 1.35rem);
    --fs-body: 1rem;
    --fs-body-lg: 1.125rem;
    --fs-small: 0.875rem;
    --fs-xs: 0.75rem;

    --fw-light: 300;
    --fw-normal: 400;
    --fw-medium: 500;
    --fw-semibold: 600;
    --fw-bold: 700;
    --fw-extrabold: 800;
    --fw-black: 900;

    --lh-tight: 1.1;
    --lh-snug: 1.25;
    --lh-normal: 1.5;
    --lh-relaxed: 1.7;

    --ls-tight: -0.02em;
    --ls-normal: 0;
    --ls-wide: 0.05em;
    --ls-wider: 0.1em;
    --ls-widest: 0.2em;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;
    --space-5xl: 8rem;

    /* Layout */
    --container-max: 1280px;
    --container-narrow: 960px;
    --container-wide: 1440px;

    /* Borders */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.6);
    --shadow-gold: 0 4px 24px rgba(201, 168, 76, 0.15);
    --shadow-gold-lg: 0 8px 40px rgba(201, 168, 76, 0.2);

    /* Transitions */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);

    --duration-fast: 200ms;
    --duration-normal: 350ms;
    --duration-slow: 500ms;
    --duration-slower: 800ms;

    /* Z-index scale */
    --z-base: 1;
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-fixed: 300;
    --z-overlay: 400;
    --z-modal: 500;
    --z-toast: 600;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-body);
    font-size: var(--fs-body);
    font-weight: var(--fw-normal);
    line-height: var(--lh-normal);
    color: var(--color-white-90);
    background-color: var(--color-bg-primary);
    overflow-x: hidden;
    min-height: 100vh;
}

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

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

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

ul, ol {
    list-style: none;
}

button, input, select, textarea {
    font-family: inherit;
    font-size: inherit;
    color: inherit;
    border: none;
    outline: none;
    background: none;
}

button {
    cursor: pointer;
}

::selection {
    background: var(--color-gold);
    color: var(--color-bg-primary);
}

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-white-10);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-gold-dark);
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: var(--fw-bold);
    line-height: var(--lh-tight);
    color: var(--color-white);
    letter-spacing: var(--ls-tight);
}

h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }
h4 { font-size: var(--fs-h4); }

p {
    color: var(--color-white-70);
    line-height: var(--lh-relaxed);
}

.text-gold { color: var(--color-gold); }
.text-white { color: var(--color-white); }
.text-muted { color: var(--color-white-50); }

/* --- Layout --- */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-xl);
}

.container--narrow {
    max-width: var(--container-narrow);
}

.container--wide {
    max-width: var(--container-wide);
}

.section {
    padding: var(--space-5xl) 0;
    position: relative;
}

.section--alt {
    background: var(--color-bg-secondary);
}

/* Section heading group */
.section-header {
    text-align: center;
    margin-bottom: var(--space-4xl);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.section-label {
    display: inline-block;
    font-family: var(--font-heading);
    font-size: var(--fs-xs);
    font-weight: var(--fw-semibold);
    letter-spacing: var(--ls-widest);
    text-transform: uppercase;
    color: var(--color-gold);
    margin-bottom: var(--space-md);
    position: relative;
    padding: var(--space-xs) var(--space-lg);
    border: 1px solid var(--color-gold-muted);
    border-radius: var(--radius-full);
    background: var(--color-gold-muted);
}

.section-title {
    margin-bottom: var(--space-lg);
}

.section-subtitle {
    font-size: var(--fs-body-lg);
    color: var(--color-white-50);
    line-height: var(--lh-relaxed);
}

/* Decorative gold line */
.gold-line {
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
    border-radius: var(--radius-full);
    margin: var(--space-lg) auto;
}

.gold-line--left {
    margin-left: 0;
}

/* --- Grid System --- */
.grid {
    display: grid;
    gap: var(--space-xl);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .grid-4, .grid-3, .grid-2 {
        grid-template-columns: 1fr;
    }

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

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

/* --- Visibility --- */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Scroll reveal animation triggers */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity var(--duration-slow) var(--ease-out),
                transform var(--duration-slow) var(--ease-out);
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 100ms; }
.reveal-delay-2 { transition-delay: 200ms; }
.reveal-delay-3 { transition-delay: 300ms; }
.reveal-delay-4 { transition-delay: 400ms; }
.reveal-delay-5 { transition-delay: 500ms; }
.reveal-delay-6 { transition-delay: 600ms; }