/* ═══════════════════════════════════════════
   MF Enterprise — Design System
   Porsche-inspired premium dark theme
   ═══════════════════════════════════════════ */

:root {
  /* ── Colors ── */
  --color-bg:             #0e0e12;
  --color-bg-elevated:    #16161c;
  --color-bg-footer:      #0a0a0e;
  --color-surface:        #1c1c24;
  --color-border:         rgba(255, 255, 255, 0.08);
  --color-text:           #ffffff;
  --color-text-secondary: rgba(255, 255, 255, 0.65);
  --color-text-tertiary:  rgba(255, 255, 255, 0.40);

  /* ── Typography ── */
  --font-family:          'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI',
                          Roboto, Helvetica, Arial, sans-serif;
  --font-weight-regular:  400;
  --font-weight-medium:   500;
  --font-weight-semibold: 600;
  --font-weight-bold:     700;
  --font-weight-black:    900;

  --text-xs:              clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm:              clamp(0.8125rem, 0.78rem + 0.2vw, 0.875rem);
  --text-base:            clamp(0.9375rem, 0.875rem + 0.3vw, 1.0625rem);
  --text-lg:              clamp(1.0625rem, 0.95rem + 0.5vw, 1.25rem);
  --text-xl:              clamp(1.25rem, 1rem + 1vw, 1.75rem);
  --text-2xl:             clamp(1.75rem, 1.25rem + 2vw, 2.75rem);
  --text-3xl:             clamp(2.25rem, 1.5rem + 3vw, 3.75rem);
  --text-display:         clamp(2.75rem, 1.75rem + 4vw, 5rem);

  --leading-tight:        1.1;
  --leading-snug:         1.25;
  --leading-normal:       1.6;
  --leading-relaxed:      1.8;

  --tracking-tight:       -0.02em;
  --tracking-normal:      0;
  --tracking-wide:        0.04em;
  --tracking-wider:       0.08em;
  --tracking-widest:      0.14em;

  /* ── Spacing (fluid) ── */
  --space-xs:             clamp(0.5rem, 0.4rem + 0.25vw, 0.75rem);
  --space-sm:             clamp(0.75rem, 0.6rem + 0.5vw, 1.25rem);
  --space-md:             clamp(1.25rem, 1rem + 1vw, 2rem);
  --space-lg:             clamp(2rem, 1.5rem + 2vw, 3.5rem);
  --space-xl:             clamp(3rem, 2rem + 3vw, 5rem);
  --space-2xl:            clamp(4rem, 2.5rem + 5vw, 8rem);
  --space-3xl:            clamp(6rem, 4rem + 6vw, 12rem);

  --padding-x:            clamp(1.25rem, 1rem + 2vw, 4rem);
  --max-width:            1320px;

  /* ── 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:        0.15s;
  --duration-short:       0.25s;
  --duration-moderate:    0.4s;
  --duration-slow:        0.6s;

  /* ── Layout ── */
  --header-height:        clamp(64px, 5vw, 88px);
}

/* ── Reset ── */

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-weight: var(--font-weight-regular);
  background-color: var(--color-bg);
  color: var(--color-text);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  padding-top: var(--header-height);
}

::selection {
  background-color: rgba(255, 255, 255, 0.15);
  color: var(--color-text);
}

/* ── Header ── */

.site-header-wrapper {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background-color: rgba(14, 14, 18, 0.85);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--color-border);
  transition: transform var(--duration-moderate) var(--ease-out);
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--padding-x);
  height: var(--header-height);
}

.site-logo {
  font-size: var(--text-sm);
  font-weight: var(--font-weight-black);
  letter-spacing: var(--tracking-widest);
  color: var(--color-text);
  text-decoration: none;
  text-transform: uppercase;
  transition: opacity var(--duration-short) var(--ease-out);
}

.site-logo:hover {
  opacity: 0.8;
}

.site-nav {
  display: flex;
  gap: var(--space-lg);
  align-items: center;
}

.site-nav a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  letter-spacing: var(--tracking-wide);
  position: relative;
  transition: color var(--duration-short) var(--ease-out);
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--color-text);
}

.site-nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background-color: var(--color-text);
  transition: width var(--duration-moderate) var(--ease-out);
}

.site-nav a:hover::after,
.site-nav a.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-text);
  cursor: pointer;
  width: 28px;
  height: 28px;
  padding: 0;
  align-items: center;
  justify-content: center;
}

/* ── Main Content ── */

main {
  flex: 1;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--padding-x);
}

/* ── Hero Section ── */

.hero {
  padding: var(--space-2xl) 0 var(--space-xl);
}

.hero h1 {
  font-size: var(--text-display);
  font-weight: var(--font-weight-bold);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  margin-bottom: var(--space-lg);
}

.hero p {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-regular);
  line-height: var(--leading-relaxed);
  color: var(--color-text-secondary);
  max-width: 52ch;
}

.hero-image {
  margin-top: var(--space-xl);
  overflow: hidden;
}

.hero-image img {
  width: 100%;
  height: auto;
  display: block;
  aspect-ratio: 21 / 9;
  object-fit: cover;
  transition: transform var(--duration-slow) var(--ease-out);
}

.hero-image:hover img {
  transform: scale(1.02);
}

/* ── Page Content (Subpages) ── */

.page-content {
  padding: var(--space-3xl) 0 var(--space-2xl);
}

.page-content h1 {
  font-size: var(--text-3xl);
  font-weight: var(--font-weight-bold);
  letter-spacing: var(--tracking-tight);
  line-height: var(--leading-tight);
  margin-bottom: var(--space-md);
}

.page-content p {
  color: var(--color-text-secondary);
  font-size: var(--text-lg);
  line-height: var(--leading-relaxed);
  max-width: 52ch;
}

.page-content a {
  color: var(--color-text);
  text-decoration-color: var(--color-text-tertiary);
  text-underline-offset: 3px;
  transition: text-decoration-color var(--duration-short) var(--ease-out);
}

.page-content a:hover {
  text-decoration-color: var(--color-text);
}

/* ── Ventures Grid ── */

.ventures-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  margin-top: var(--space-xl);
  background-color: var(--color-border);
  border: 1px solid var(--color-border);
}

.venture-card {
  background-color: var(--color-bg);
  padding: var(--space-lg) var(--space-md);
  text-decoration: none;
  color: inherit;
  transition: background-color var(--duration-short) var(--ease-out);
}

a.venture-card:hover {
  background-color: var(--color-bg-elevated);
}

.venture-card h2 {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  letter-spacing: var(--tracking-tight);
  margin-bottom: var(--space-xs);
}

.venture-card p {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: var(--leading-normal);
}

@media (max-width: 768px) {
  .ventures-grid {
    grid-template-columns: 1fr;
  }
}

/* ── Footer ── */

.site-footer {
  background-color: var(--color-bg-footer);
  margin-top: auto;
  border-top: 1px solid var(--color-border);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-xl) var(--padding-x);
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
}

.footer-info p {
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--color-text-secondary);
  letter-spacing: var(--tracking-wide);
}

.footer-info .footer-email {
  margin-top: var(--space-md);
}

.footer-info .footer-email a {
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--duration-short) var(--ease-out);
}

.footer-info .footer-email a:hover {
  color: var(--color-text);
}

.footer-info .nipc {
  margin-top: var(--space-md);
  font-size: var(--text-xs);
  color: var(--color-text-tertiary);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
}


/* ── Mobile Nav Overlay ── */

.site-nav-mobile {
  display: none;
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(14, 14, 18, 0.97);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-xl);
  z-index: 99;
}

.site-nav-mobile.open {
  display: flex;
}

.site-nav-mobile a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: var(--text-xl);
  font-weight: var(--font-weight-semibold);
  letter-spacing: var(--tracking-wide);
  transition: color var(--duration-short) var(--ease-out);
}

.site-nav-mobile a:hover {
  color: var(--color-text);
}

/* ── Responsive ── */

@media (max-width: 768px) {
  .site-nav {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .footer-inner {
    flex-direction: column;
    gap: var(--space-lg);
    align-items: flex-start;
  }
}