/* ==========================================================
   BeatCharts — styles.css
   ========================================================== */

/* ── Custom Properties ─────────────────────────────────── */
:root {
  --green:     #00FF87;
  --black:     #000000;
  --gray-900:  #0d0d0d;
  --gray-800:  #1a1a1a;
  --gray-700:  #2a2a2a;
  --gray-500:  #4d4d4d;
  --gray-400:  #666666;
  --gray-300:  #999999;
  --gray-100:  #cccccc;
  --white:     #f5f5f0;

  --font-display: 'Bebas Neue', 'Anton', sans-serif;
  --font-mono:    'JetBrains Mono', 'Space Mono', monospace;
  --font-body:    'Inter', sans-serif;
  --font-jp:      'Noto Sans JP', sans-serif;

  --header-h:  56px;
  --filter-h:  48px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background: var(--black);
  color: var(--white);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  cursor: pointer;
  background: none;
  border: none;
  font-family: inherit;
}

/* ── Header ────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(0, 0, 0, 0.94);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--gray-800);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 24px;
}

.logo {
  font-family: 'Big Shoulders Display', sans-serif;
  font-weight: 900;
  font-size: 24px;
  letter-spacing: 0.01em;
  color: var(--white);
  flex-shrink: 0;
  line-height: 1;
}

/* Nav */
.site-nav {
  display: flex;
  align-items: center;
  gap: 2px;
  flex: 1;
}

.nav-tab {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--gray-400);
  padding: 6px 12px;
  border-radius: 3px;
  transition: color 0.15s, background 0.15s;
}

.nav-tab:hover {
  color: var(--white);
  background: rgba(255, 255, 255, 0.05);
}

.nav-tab.active {
  color: var(--green);
  background: rgba(0, 255, 135, 0.08);
}

.nav-link {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--gray-400);
  padding: 6px 12px;
  border-radius: 3px;
  transition: color 0.15s, background 0.15s;
}

.nav-link:hover {
  color: var(--white);
  background: rgba(255, 255, 255, 0.05);
}

/* PRODUCERS — dimmed (coming soon) */
.nav-dim {
  opacity: 0.4;
  pointer-events: none;
}

/* Top-right badge */
.index-badge {
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--gray-400);
  border: 1px solid var(--gray-700);
  padding: 4px 9px;
  border-radius: 2px;
  flex-shrink: 0;
  white-space: nowrap;
}

/* ── Hero ──────────────────────────────────────────────── */
.hero {
  padding: 48px 24px 32px;
  border-bottom: 1px solid var(--gray-800);
}

.hero-inner {
  max-width: 1200px;
  margin: 0 auto;
}

.chart-period-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--green);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.chart-title {
  font-family: var(--font-display);
  font-size: clamp(72px, 12vw, 160px);
  font-style: italic;
  line-height: 0.88;
  letter-spacing: -0.02em;
  color: var(--white);
  margin-bottom: 20px;
}

.chart-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--gray-400);
  text-transform: uppercase;
  line-height: 1;
}

.meta-sep {
  color: var(--gray-700);
}

/* ── Filter Bar ────────────────────────────────────────── */
.filter-bar-wrapper {
  position: sticky;
  top: var(--header-h);
  z-index: 90;
  background: var(--gray-900);
  border-bottom: 1px solid var(--gray-800);
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 10px 24px;
  height: var(--filter-h);
}

.filter-bar {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: none;
  flex: 1;
  padding-bottom: 1px;
}

.filter-bar::-webkit-scrollbar {
  display: none;
}

.filter-chip {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  white-space: nowrap;
  padding: 5px 11px;
  border: 1px solid var(--gray-700);
  border-radius: 2px;
  color: var(--gray-400);
  background: transparent;
  transition: border-color 0.12s, color 0.12s, background 0.12s;
  flex-shrink: 0;
}

.filter-chip:hover {
  border-color: var(--gray-400);
  color: var(--white);
}

.filter-chip.active {
  background: var(--green);
  border-color: var(--green);
  color: var(--black);
}

.filter-count {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--gray-400);
  flex-shrink: 0;
  white-space: nowrap;
}

/* ── Chart Main ────────────────────────────────────────── */
.chart-main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px 80px;
}

/* Column header row */
.chart-header-row {
  display: grid;
  grid-template-columns: 56px 72px 1fr 130px 48px;
  gap: 12px;
  align-items: center;
  padding: 10px 16px;
  border-bottom: 1px solid var(--gray-800);
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--gray-500);
  text-transform: uppercase;
}

.col-plays { text-align: right; }

/* ── Chart Row ─────────────────────────────────────────── */
.chart-list {
  display: flex;
  flex-direction: column;
}

.chart-row {
  display: grid;
  grid-template-columns: 56px 72px 1fr 130px 48px;
  gap: 12px;
  align-items: center;
  padding: 12px 16px;
  border-bottom: 1px solid var(--gray-800);
  transition: background 0.1s;
  min-height: 68px;
}

.chart-row:hover {
  background: rgba(255, 255, 255, 0.025);
}

/* Rank number */
.rank-num {
  font-family: var(--font-display);
  font-size: 30px;
  font-style: italic;
  letter-spacing: -0.02em;
  line-height: 1;
  color: var(--gray-700);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
}

.chart-row.rank-top .rank-num {
  color: var(--green);
}

/* Trend badge below rank */
.rank-trend {
  font-family: var(--font-mono);
  font-size: 8px;
  font-style: normal;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1;
}

.trend-new  { color: var(--green); }
.trend-up   { color: #5bc8f5; }
.trend-down { color: #f56b5b; }
.trend-same { color: var(--gray-500); }

/* Thumbnail placeholder */
.thumb {
  width: 64px;
  height: 36px;
  border-radius: 2px;
  overflow: hidden;
  flex-shrink: 0;
}

.thumb-inner {
  width: 100%;
  height: 100%;
  position: relative;
}

/* Thin green left-edge accent on placeholder */
.thumb-inner::after {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--green);
  opacity: 0.25;
}

/* Track info */
.track-info {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.track-title {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  color: var(--white);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  line-height: 1.3;
}

.track-channel {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--gray-400);
  letter-spacing: 0.04em;
}

.track-sub {
  display: flex;
  align-items: center;
  gap: 8px;
}

.track-date {
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--gray-700);
  letter-spacing: 0.04em;
}

.genre-tag {
  font-family: var(--font-mono);
  font-size: 8px;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 2px 6px;
  border: 1px solid var(--gray-700);
  border-radius: 2px;
  color: var(--gray-500);
  white-space: nowrap;
  flex-shrink: 0;
}

/* Plays count */
.plays-cell {
  text-align: right;
}

.plays-count {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--white);
  letter-spacing: -0.02em;
  display: block;
  line-height: 1.2;
}

.plays-label {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: 0.1em;
  color: var(--gray-500);
  display: block;
  margin-top: 2px;
}

/* Play button */
.play-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--gray-700);
  border-radius: 50%;
  color: var(--gray-400);
  transition: border-color 0.15s, color 0.15s, background 0.15s;
  justify-self: center;
  flex-shrink: 0;
}

.play-btn:hover {
  border-color: var(--green);
  color: var(--green);
  background: rgba(0, 255, 135, 0.08);
}

.play-btn svg {
  width: 13px;
  height: 13px;
  fill: currentColor;
  margin-left: 1px; /* optical centering for triangle */
}

/* No results state */
.no-results {
  padding: 64px 16px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--gray-500);
  text-transform: uppercase;
}

/* ── About Section ─────────────────────────────────────── */
.about-section {
  background: var(--gray-900);
  border-top: 1px solid var(--gray-800);
  padding: 72px 24px;
}

.about-inner {
  max-width: 1200px;
  margin: 0 auto;
}

.about-title {
  font-family: var(--font-display);
  font-size: 56px;
  font-style: italic;
  color: var(--white);
  letter-spacing: 0.02em;
  margin-bottom: 48px;
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 40px 48px;
}

.about-block h3 {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--green);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.about-block p {
  font-size: 13px;
  line-height: 1.75;
  color: var(--gray-300);
  font-family: var(--font-jp);
}

.about-block a {
  color: var(--green);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ── Footer ────────────────────────────────────────────── */
.site-footer {
  padding: 20px 24px;
  border-top: 1px solid var(--gray-800);
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--gray-500);
}

/* ── Responsive ────────────────────────────────────────── */
@media (max-width: 768px) {
  .header-inner {
    padding: 0 16px;
    gap: 10px;
  }

  .index-badge {
    display: none;
  }

  .nav-link.nav-dim {
    display: none;
  }

  .hero {
    padding: 32px 16px 24px;
  }

  .filter-bar-wrapper {
    padding: 10px 16px;
  }

  .chart-main {
    padding: 0 0 64px;
  }

  .chart-header-row {
    display: none;
  }

  /* Mobile grid: hide plays label, tighten columns */
  .chart-row {
    grid-template-columns: 44px 56px 1fr 80px 36px;
    gap: 8px;
    padding: 10px 16px;
    min-height: 60px;
  }

  .rank-num {
    font-size: 24px;
  }

  .thumb {
    width: 56px;
    height: 32px;
  }

  .track-title {
    font-size: 12px;
  }

  .genre-tag {
    display: none;
  }

  .plays-count {
    font-size: 12px;
  }

  .about-section {
    padding: 48px 16px;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}

@media (max-width: 480px) {
  .chart-row {
    grid-template-columns: 38px 52px 1fr 68px 32px;
    gap: 6px;
    padding: 8px 12px;
  }

  .thumb {
    width: 52px;
    height: 29px;
  }

  .plays-count {
    font-size: 11px;
  }

  .plays-label {
    display: none;
  }

  .nav-tab {
    font-size: 10px;
    padding: 5px 8px;
  }
}