/* ========================================
   LCSU — Main CSS (Design System)
   ======================================== */

/* ── CSS Custom Properties ─────────────── */
:root {
    --lcsu-primary: #38BDF8;
    --lcsu-primary-dark: #0EA5E9;
    --lcsu-primary-light: #BAE6FD;
    --lcsu-primary-ultra: #E0F2FE;
    --lcsu-white: #FFFFFF;
    --lcsu-surface: #F8FAFC;
    --lcsu-text: #0F172A;
    --lcsu-text-secondary: #64748B;
    --lcsu-border: #E2E8F0;
    --lcsu-dark: #1E293B;
    --lcsu-shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --lcsu-shadow: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
    --lcsu-shadow-md: 0 10px 25px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.05);
    --lcsu-shadow-lg: 0 20px 50px -10px rgba(0,0,0,0.1);
    --lcsu-shadow-glow: 0 0 30px rgba(56,189,248,0.15);
    --lcsu-radius: 12px;
    --lcsu-radius-lg: 16px;
    --lcsu-radius-xl: 24px;
    --lcsu-radius-full: 9999px;
    --lcsu-font: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --lcsu-transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --lcsu-container: 1200px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--lcsu-font);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--lcsu-text);
    background: var(--lcsu-white);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--lcsu-text);
}
h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.25rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }
h4 { font-size: 1.125rem; }

p { margin-bottom: 1rem; }

/* ── Container ─────────────────────────── */
.lcsu-container {
    width: 100%;
    max-width: var(--lcsu-container);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ── Section ───────────────────────────── */
.lcsu-section {
    padding: 5rem 0;
}
.lcsu-section--surface { background: var(--lcsu-surface); }
.lcsu-section--dark { background: var(--lcsu-dark); color: var(--lcsu-white); }

.lcsu-section__header {
    text-align: center;
    margin-bottom: 3.5rem;
}
.lcsu-section__badge {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    background: var(--lcsu-primary-ultra);
    color: var(--lcsu-primary-dark);
    font-size: 0.8125rem;
    font-weight: 600;
    padding: 0.375rem 1rem;
    border-radius: var(--lcsu-radius-full);
    margin-bottom: 1rem;
    letter-spacing: 0.025em;
}
.lcsu-section__title {
    margin-bottom: 0.75rem;
}
.lcsu-section__subtitle {
    color: var(--lcsu-text-secondary);
    font-size: 1.0625rem;
    max-width: 600px;
    margin: 0 auto;
}

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

/* ── Utility ───────────────────────────── */
.lcsu-text-center { text-align: center; }
.lcsu-text-gradient {
    background: linear-gradient(135deg, var(--lcsu-primary-dark), var(--lcsu-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.lcsu-sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    border: 0;
}