/* Reset & Core Design System */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-weight: 400 !important; /* Strict Requirement: Font Weight ONLY 400 across entire site */
}

:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-text-main: #000000;
  --color-text-white: #ffffff;
  --color-overlay: rgba(0, 0, 0, 0.25);
  
  /* Fonts */
  --font-sans: 'IBM Plex Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;
  
  /* Strict Font Sizes: 40px and 20px (with responsive fluid clamping for mobile adaptability) */
  --font-size-40: clamp(24px, 2.5vw, 40px);
  --font-size-20: clamp(14px, 1.3vw, 20px);
  
  /* Layout Spacing (Strict Grid Padding 50px) */
  --page-padding: 50px;
  --grid-gap-50: 50px;
  --margin-mt-150: 150px;
  --margin-mb-500: 500px;
}

@media (max-width: 768px) {
  :root {
    --page-padding: 24px;
    --grid-gap-50: 30px;
    --margin-mt-150: 80px;
    --margin-mb-500: 160px;
  }
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--color-bg);
  color: var(--color-text-main);
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text-main);
  line-height: 1.4;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Site Container using CSS Grid */
.site-container {
  display: grid;
  grid-template-columns: 1fr;
  width: 100%;
  min-height: 100vh;
}

/* ==========================================================================
   Part 1: Hero Section (100vh, Slideshow background, Logo w100%, Linktree text)
   ========================================================================== */
.hero-section {
  position: relative;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  display: grid;
  grid-template-rows: 1fr;
  grid-template-columns: 1fr;
  align-items: center;
  justify-items: center;
  overflow: hidden;
  padding: var(--page-padding);
}

/* Background Slideshow */
.hero-slideshow {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

.hero-slideshow .slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover; /* Responsive image fit */
  object-position: center;
  opacity: 0;
  transition: opacity 1.2s ease-in-out;
  pointer-events: none;
}

.hero-slideshow .slide.active {
  opacity: 1;
}

/* Overlay dark tint for contrast */
.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--color-overlay);
  z-index: 2;
  pointer-events: none;
}

/* Hero Content Grid Overlay */
.hero-content {
  position: relative;
  z-index: 3;
  width: 100%;
  height: 100%;
  display: grid;
  grid-template-rows: 1fr auto;
  align-items: end; /* Pinned to bottom */
  justify-items: center;
  padding-bottom: 10px;
}

.logo-wrapper {
  grid-row: 1;
  width: 100%;
  display: grid;
  place-items: center;
  align-self: end; /* Pinned to hero bottom */
  margin-bottom: 8px; /* Small margin */
}

/* Logo 100% width fit grid div */
.hero-logo {
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: contain;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.15));
}

.desktop-logo {
  display: block;
}

.mobile-logo-stack {
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.mobile-logo-stack .logo-part {
  max-width: 80%;
  height: auto;
}

/* <LINKTREE DOWNBELOW> text - Only on Desktop */
.linktree-downbelow {
  grid-row: 2;
  font-family: var(--font-mono);
  font-size: var(--font-size-20);
  color: var(--color-text-white);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 8px; /* Small margin */
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
  user-select: none;
}

@media (max-width: 768px) {
  .linktree-downbelow {
    display: none; /* Requirement: Only on desktop */
  }

  .desktop-logo {
    display: none;
  }

  .mobile-logo-stack {
    display: flex;
  }
}

/* ==========================================================================
   Part 2: Links Section (IBM Plex Mono, Font 40px, Margin 50px, Gap 50px)
   ========================================================================== */
.links-section {
  padding: 0 var(--page-padding);
  margin: 50px 0;
  width: 100%;
}

.links-grid {
  display: grid;
  /* Desktop grid layout: 3 columns matching Figma */
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: var(--grid-gap-50);
  align-items: start;
  font-family: var(--font-mono);
  font-size: var(--font-size-40);
  line-height: 1.3;
}

.grid-col {
  word-break: break-word;
}

.brand-title, .linktree-title {
  color: var(--color-text-main);
  text-transform: uppercase;
}

.social-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.social-link {
  color: var(--color-text-main);
  text-decoration: underline;
  text-underline-offset: 6px;
  text-decoration-thickness: 1.5px;
  transition: opacity 0.2s ease, text-decoration-color 0.2s ease, transform 0.2s ease;
  display: inline-block;
}

.social-link:hover {
  opacity: 0.65;
  transform: translateX(4px);
}

.social-link .arrow {
  display: inline-block;
  margin-left: 2px;
  font-size: 0.9em;
}

/* Responsive links layout for Tablet & Mobile */
@media (max-width: 1024px) {
  .links-grid {
    grid-template-columns: 1fr 1fr;
  }

  .social-links-col {
    grid-column: 1 / -1;
    margin-top: 20px;
  }
}

@media (max-width: 600px) {
  .links-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

/* ==========================================================================
   Part 3: Statement Section (IBM Plex Sans JP 40px, mt-150, mb-500)
   ========================================================================== */
.statement-section {
  padding: 0 var(--page-padding);
  margin-top: var(--margin-mt-150);
  margin-bottom: var(--margin-mb-500);
  width: 100%;
}

.statement-container {
  display: grid;
  grid-template-columns: 1fr;
  max-width: 100%;
}

.statement-text {
  font-family: var(--font-sans);
  font-size: var(--font-size-40);
  line-height: 1.45;
  color: var(--color-text-main);
  letter-spacing: -0.01em;
}

/* ==========================================================================
   Part 4: Footer Copyright Section (IBM Plex Mono 20px)
   ========================================================================== */
.site-footer {
  padding: 10px var(--page-padding) 16px var(--page-padding);
  width: 100%;
  display: grid;
  place-items: center;
}

.copyright-text {
  font-family: var(--font-mono);
  font-size: var(--font-size-20);
  color: var(--color-text-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-align: center;
}