/*
============================================================
BASE.CSS - DARK THEME
============================================================
*/
:root {
    --bg-primary:    #080d1a;
    --bg-secondary:  #0c1120;
    --bg-card:       #101828;
    --bg-card-hover: #141f30;

    --primary:       #4ade80;
    --primary-light: #86efac;
    --primary-dark:  #22c55e;
    --accent:        #22d3ee;
    --accent-purple: #a78bfa;

    --text-primary:   #f1f5f9;
    --text-secondary: #94a3b8;
    --text-tertiary:  #475569;

    --border-light:  rgba(255, 255, 255, 0.07);
    --border-medium: rgba(255, 255, 255, 0.13);

    --shadow-sm:  0 1px 4px rgba(0,0,0,0.5);
    --shadow-md:  0 4px 16px rgba(0,0,0,0.6);
    --shadow-lg:  0 10px 40px rgba(0,0,0,0.7);
    --shadow-xl:  0 20px 60px rgba(0,0,0,0.8);
    --glow-green: 0 0 30px rgba(74,222,128,0.25);
    --glow-cyan:  0 0 30px rgba(34,211,238,0.20);

    --section-padding: 90px;
    --container-padding: 24px;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 72px;
}

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

body {
    overflow-x: hidden;
    width: 100%;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
    pointer-events: none;
    z-index: 0;
    opacity: 0.4;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--container-padding);
    position: relative;
    z-index: 1;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

h1 { font-size: clamp(2.25rem, 5vw, 3.75rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.5rem);  letter-spacing: -0.01em; margin-bottom: 1rem; }
h3 { font-size: clamp(1.15rem, 2.5vw, 1.5rem); }

p {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

/* Section */
.section {
    padding: var(--section-padding) 0;
    position: relative;
}

.section h2 {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
    display: block;
}

.section h2::after {
    content: '';
    position: absolute;
    bottom: -12px;
    left: 50%;
    transform: translateX(-50%);
    width: 44px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    border-radius: 2px;
}

a {
    text-decoration: none;
    color: var(--primary);
    transition: color 0.25s ease;
}

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

button, .btn {
    cursor: pointer;
    border: none;
    font-family: inherit;
    font-weight: 600;
    transition: all 0.25s ease;
}

/* Scroll Reveal */
.reveal {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

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

.reveal-delay-1 { transition-delay: 0.08s; }
.reveal-delay-2 { transition-delay: 0.16s; }
.reveal-delay-3 { transition-delay: 0.24s; }
.reveal-delay-4 { transition-delay: 0.32s; }

/* Skip link */
.skip-link {
    position: absolute;
    top: -100px;
    left: 1rem;
    background: var(--primary);
    color: #000;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    font-weight: 600;
    z-index: 9999;
}

.skip-link:focus { top: 1rem; }

/* Animations */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* ── Tablet (≤ 1024px) ── */
@media (max-width: 1024px) {
    :root { --section-padding: 72px; }
}

/* ── Mobile (≤ 768px) ── */
@media (max-width: 768px) {
    :root {
        --section-padding: 56px;
        --container-padding: 20px;
    }

    .section h2 { margin-bottom: 2.25rem; }

    .reveal-delay-1 { transition-delay: 0.05s; }
    .reveal-delay-2 { transition-delay: 0.10s; }
    .reveal-delay-3 { transition-delay: 0.15s; }
    .reveal-delay-4 { transition-delay: 0.20s; }
}

/* ── Small mobile (≤ 480px) ── */
@media (max-width: 480px) {
    :root { --container-padding: 16px; }
}

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