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

:root {
  /* Backgrounds */
  --bg-deep: #0a0a0f;
  --bg-surface: #111118;
  --bg-elevated: #1a1a24;
  --bg-glass: rgba(17, 17, 24, 0.75);

  /* Text */
  --text-primary: #f0eef6;
  --text-secondary: rgba(240, 238, 246, 0.7);
  --text-muted: rgba(240, 238, 246, 0.4);

  /* Category colors */
  --cat-alkali-metal: #e84393;
  --cat-alkaline-earth: #fd9644;
  --cat-transition-metal: #4a9ef5;
  --cat-post-transition: #26c6da;
  --cat-metalloid: #2ed573;
  --cat-nonmetal: #a29bfe;
  --cat-halogen: #feca57;
  --cat-noble-gas: #ff6b6b;
  --cat-lanthanide: #f368e0;
  --cat-actinide: #ff9ff3;

  /* Glass */
  --glass-border: rgba(240, 238, 246, 0.08);
  --glass-blur: 16px;

  /* Sizing */
  --cell-size: clamp(42px, 4vw, 64px);
  --cell-gap: 3px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;

  /* Fonts */
  --font-display: 'Oxanium', cursive;
  --font-body: 'Outfit', sans-serif;
  --font-mono: 'Fira Code', monospace;

  color-scheme: dark;
}

html {
  font-family: var(--font-body);
  background: var(--bg-deep);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100dvh;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 50% 50%, rgba(74, 158, 245, 0.03) 0%, transparent 70%),
    repeating-radial-gradient(
      circle at 0 0,
      transparent 0,
      transparent 9px,
      rgba(240, 238, 246, 0.012) 9px,
      rgba(240, 238, 246, 0.012) 10px
    ),
    var(--bg-deep);
}

/* === App shell === */
.app {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  padding: 1.5rem;
  gap: 1.5rem;
  max-width: 1440px;
  margin: 0 auto;
}

/* === Controls header === */
.controls {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, var(--text-primary) 0%, rgba(162, 155, 254, 0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.controls-right {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

/* === Table wrapper === */
.table-wrapper {
  flex: 1;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  padding-bottom: 2rem;
}

/* === Periodic Table Grid === */
.periodic-table {
  display: grid;
  grid-template-columns: repeat(18, var(--cell-size));
  grid-template-rows: repeat(7, var(--cell-size)) calc(var(--cell-size) * 0.4) repeat(2, var(--cell-size));
  gap: var(--cell-gap);
  width: fit-content;
}

/* === Element Cell === */
.element-cell {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: var(--cell-size);
  height: var(--cell-size);
  border-radius: var(--radius-sm);
  border: 1px solid var(--glass-border);
  background: var(--bg-surface);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, opacity 0.3s ease, filter 0.3s ease;
  overflow: hidden;
  user-select: none;
}

.element-cell .atomic-number {
  position: absolute;
  top: 2px;
  left: 3px;
  font-family: var(--font-mono);
  font-size: clamp(0.45rem, 0.7vw, 0.6rem);
  color: var(--text-muted);
  line-height: 1;
}

.element-cell .symbol {
  font-family: var(--font-mono);
  font-size: clamp(0.85rem, 1.4vw, 1.2rem);
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.1;
}

.element-cell .name {
  font-family: var(--font-body);
  font-size: clamp(0.35rem, 0.55vw, 0.48rem);
  font-weight: 400;
  color: var(--text-secondary);
  line-height: 1;
  max-width: 90%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.element-cell .mass {
  font-family: var(--font-mono);
  font-size: clamp(0.32rem, 0.48vw, 0.42rem);
  color: var(--text-muted);
  line-height: 1;
  margin-top: 1px;
}

/* === Lanthanide / Actinide labels === */
.series-label {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding-right: 8px;
  font-family: var(--font-mono);
  font-size: clamp(0.45rem, 0.6vw, 0.55rem);
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

/* === Category Color Coding === */
.element-cell[data-category="alkali-metal"] {
  --cat-color: var(--cat-alkali-metal);
  background: linear-gradient(135deg, rgba(232, 67, 147, 0.18), rgba(232, 67, 147, 0.06));
  border-color: rgba(232, 67, 147, 0.25);
}
.element-cell[data-category="alkaline-earth"] {
  --cat-color: var(--cat-alkaline-earth);
  background: linear-gradient(135deg, rgba(253, 150, 68, 0.18), rgba(253, 150, 68, 0.06));
  border-color: rgba(253, 150, 68, 0.25);
}
.element-cell[data-category="transition-metal"] {
  --cat-color: var(--cat-transition-metal);
  background: linear-gradient(135deg, rgba(74, 158, 245, 0.18), rgba(74, 158, 245, 0.06));
  border-color: rgba(74, 158, 245, 0.25);
}
.element-cell[data-category="post-transition"] {
  --cat-color: var(--cat-post-transition);
  background: linear-gradient(135deg, rgba(38, 198, 218, 0.18), rgba(38, 198, 218, 0.06));
  border-color: rgba(38, 198, 218, 0.25);
}
.element-cell[data-category="metalloid"] {
  --cat-color: var(--cat-metalloid);
  background: linear-gradient(135deg, rgba(46, 213, 115, 0.18), rgba(46, 213, 115, 0.06));
  border-color: rgba(46, 213, 115, 0.25);
}
.element-cell[data-category="nonmetal"] {
  --cat-color: var(--cat-nonmetal);
  background: linear-gradient(135deg, rgba(162, 155, 254, 0.18), rgba(162, 155, 254, 0.06));
  border-color: rgba(162, 155, 254, 0.25);
}
.element-cell[data-category="halogen"] {
  --cat-color: var(--cat-halogen);
  background: linear-gradient(135deg, rgba(254, 202, 87, 0.18), rgba(254, 202, 87, 0.06));
  border-color: rgba(254, 202, 87, 0.25);
}
.element-cell[data-category="noble-gas"] {
  --cat-color: var(--cat-noble-gas);
  background: linear-gradient(135deg, rgba(255, 107, 107, 0.18), rgba(255, 107, 107, 0.06));
  border-color: rgba(255, 107, 107, 0.25);
}
.element-cell[data-category="lanthanide"] {
  --cat-color: var(--cat-lanthanide);
  background: linear-gradient(135deg, rgba(243, 104, 224, 0.18), rgba(243, 104, 224, 0.06));
  border-color: rgba(243, 104, 224, 0.25);
}
.element-cell[data-category="actinide"] {
  --cat-color: var(--cat-actinide);
  background: linear-gradient(135deg, rgba(255, 159, 243, 0.18), rgba(255, 159, 243, 0.06));
  border-color: rgba(255, 159, 243, 0.25);
}

/* Category accent stripe */
.element-cell::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 2px;
  height: 100%;
  background: var(--cat-color, transparent);
  opacity: 0.6;
}

/* === Hover State === */
.element-cell:hover {
  transform: scale(1.25);
  z-index: 10;
  box-shadow:
    0 0 16px rgba(0, 0, 0, 0.4),
    0 0 24px color-mix(in srgb, var(--cat-color, #4a9ef5) 35%, transparent);
}

/* === Tooltip === */
.tooltip {
  position: fixed;
  z-index: 100;
  min-width: 200px;
  max-width: 260px;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  background: rgba(17, 17, 24, 0.92);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--glass-border);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
  pointer-events: none;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.15s ease, transform 0.15s ease;
}

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

.tooltip-header {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 8px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--glass-border);
}

.tooltip-symbol {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--cat-color, var(--text-primary));
}

.tooltip-name {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
}

.tooltip-number {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-muted);
  margin-left: auto;
}

.tooltip-row {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  color: var(--text-secondary);
  padding: 2px 0;
}

.tooltip-row span:first-child {
  color: var(--text-muted);
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.tooltip-category {
  display: inline-block;
  margin-top: 6px;
  padding: 2px 8px;
  border-radius: 99px;
  font-size: 0.6rem;
  font-weight: 500;
  letter-spacing: 0.03em;
  color: var(--cat-color, var(--text-secondary));
  border: 1px solid color-mix(in srgb, var(--cat-color, #888) 30%, transparent);
  background: color-mix(in srgb, var(--cat-color, #888) 8%, transparent);
}

/* === Modal === */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.modal-card {
  position: relative;
  width: 90%;
  max-width: 440px;
  background: rgba(17, 17, 24, 0.95);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.6);
  overflow: hidden;
  transform: scale(0.92);
  transition: transform 0.25s ease;
}

.modal-overlay.open .modal-card {
  transform: scale(1);
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 2;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--glass-border);
  border-radius: 50%;
  color: var(--text-secondary);
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.modal-close:hover {
  background: rgba(255, 255, 255, 0.12);
  color: var(--text-primary);
}

.modal-accent {
  height: 4px;
  background: var(--cat-color, var(--cat-transition-metal));
}

.modal-header {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 24px 24px 0;
}

.modal-symbol-block {
  width: 72px;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 600;
  color: var(--text-primary);
  border: 1px solid color-mix(in srgb, var(--cat-color, #888) 30%, transparent);
  background: color-mix(in srgb, var(--cat-color, #888) 12%, transparent);
}

.modal-title-group {
  flex: 1;
}

.modal-element-name {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
}

.modal-element-sub {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.modal-body {
  padding: 20px 24px 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.modal-info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.modal-info-item {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--glass-border);
}

.modal-info-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.modal-info-value {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text-primary);
}

.modal-fun-fact {
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--cat-color, #888) 6%, transparent);
  border-left: 3px solid var(--cat-color, var(--cat-transition-metal));
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--text-secondary);
  font-style: italic;
}

/* === Search === */
.search-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.search-icon {
  position: absolute;
  left: 10px;
  color: var(--text-muted);
  pointer-events: none;
}

.search-input {
  width: 220px;
  padding: 8px 32px 8px 32px;
  font-family: var(--font-body);
  font-size: 0.8rem;
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--glass-border);
  border-radius: 99px;
  outline: none;
  transition: border-color 0.2s, background 0.2s, width 0.3s;
}

.search-input::placeholder {
  color: var(--text-muted);
}

.search-input:focus {
  border-color: rgba(162, 155, 254, 0.4);
  background: rgba(255, 255, 255, 0.06);
}

.search-clear {
  position: absolute;
  right: 6px;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  border-radius: 50%;
  transition: color 0.2s, background 0.2s;
}

.search-clear:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.08);
}

/* === Dimmed / Matched states === */
.element-cell.dimmed {
  opacity: 0.08;
  filter: grayscale(1);
  pointer-events: none;
}

.element-cell.matched {
  animation: matchPulse 0.3s ease;
}

@keyframes matchPulse {
  0% { box-shadow: 0 0 0 0 rgba(162, 155, 254, 0.4); }
  50% { box-shadow: 0 0 12px 2px rgba(162, 155, 254, 0.25); }
  100% { box-shadow: none; }
}

/* === Category Filter Buttons === */
.category-filters {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  align-items: center;
}

.cat-btn {
  padding: 5px 12px;
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--glass-border);
  border-radius: 99px;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.cat-btn:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-primary);
}

.cat-btn.active {
  color: var(--btn-color, var(--text-primary));
  border-color: color-mix(in srgb, var(--btn-color, var(--text-primary)) 50%, transparent);
  background: color-mix(in srgb, var(--btn-color, var(--text-primary)) 12%, transparent);
  box-shadow: 0 0 12px color-mix(in srgb, var(--btn-color, var(--text-primary)) 20%, transparent);
}

.cat-btn[data-cat="all"] {
  --btn-color: var(--text-primary);
}

/* === Temperature Control === */
.temp-control {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
}

.temp-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  white-space: nowrap;
}

.temp-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 180px;
  height: 4px;
  border-radius: 2px;
  background: linear-gradient(90deg, #4a9ef5 0%, #a29bfe 25%, #fd9644 60%, #ff6b6b 100%);
  outline: none;
  cursor: pointer;
}

.temp-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--text-primary);
  border: 2px solid var(--bg-deep);
  box-shadow: 0 0 8px rgba(162, 155, 254, 0.4);
  cursor: pointer;
  transition: box-shadow 0.2s;
}

.temp-slider::-webkit-slider-thumb:hover {
  box-shadow: 0 0 14px rgba(162, 155, 254, 0.6);
}

.temp-slider::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--text-primary);
  border: 2px solid var(--bg-deep);
  box-shadow: 0 0 8px rgba(162, 155, 254, 0.4);
  cursor: pointer;
}

.temp-display {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-primary);
  min-width: 60px;
  text-align: center;
}

.temp-presets {
  display: flex;
  gap: 4px;
}

.temp-preset {
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.temp-preset:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.08);
}

.temp-preset.active {
  color: var(--text-primary);
  border-color: rgba(162, 155, 254, 0.4);
  background: rgba(162, 155, 254, 0.1);
}

/* === State indicators on cells === */
.element-cell .state-dot {
  position: absolute;
  bottom: 2px;
  right: 3px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  transition: all 0.3s ease;
}

.element-cell .state-dot.solid {
  background: var(--text-primary);
}

.element-cell .state-dot.liquid {
  background: var(--cat-color, #4a9ef5);
  box-shadow: 0 0 4px var(--cat-color, #4a9ef5);
}

.element-cell .state-dot.gas {
  background: transparent;
  border: 1px solid var(--text-secondary);
}

.element-cell .state-dot.unknown {
  width: 5px;
  height: 1px;
  border-radius: 0;
  background: var(--text-muted);
}

/* === Responsive === */
@media (max-width: 1199px) {
  :root {
    --cell-size: clamp(38px, 3.5vw, 52px);
  }

  .temp-slider {
    width: 140px;
  }

  .search-input {
    width: 180px;
  }
}

@media (max-width: 899px) {
  :root {
    --cell-size: 44px;
  }

  .app {
    padding: 1rem;
    gap: 1rem;
  }

  .controls {
    flex-direction: column;
    align-items: stretch;
  }

  .controls-right {
    justify-content: stretch;
  }

  .search-input {
    width: 100%;
  }

  .search-wrap {
    flex: 1;
  }

  .temp-control {
    flex-wrap: wrap;
    justify-content: center;
  }

  .category-filters {
    overflow-x: auto;
    flex-wrap: nowrap;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

  .category-filters::-webkit-scrollbar {
    display: none;
  }

  .periodic-table {
    min-width: calc(18 * 44px + 17 * 3px);
  }
}

@media (max-width: 479px) {
  :root {
    --cell-size: 40px;
  }

  .element-cell .name {
    display: none;
  }

  .element-cell .mass {
    display: none;
  }

  .temp-presets {
    width: 100%;
    justify-content: center;
  }

  .modal-card {
    width: 96%;
    max-height: 90dvh;
    overflow-y: auto;
  }

  .modal-info-grid {
    grid-template-columns: 1fr;
  }

  .periodic-table {
    min-width: calc(18 * 40px + 17 * 3px);
  }
}

/* === Load Animation === */
@keyframes cellFadeIn {
  from {
    opacity: 0;
    transform: scale(0.85) translateY(4px);
  }
  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

.element-cell {
  animation: cellFadeIn 0.4s ease both;
}

/* === Focus ring for keyboard nav === */
.element-cell:focus-visible {
  outline: 2px solid var(--cat-color, var(--cat-transition-metal));
  outline-offset: 1px;
  z-index: 5;
}

/* === Selection highlight === */
::selection {
  background: rgba(162, 155, 254, 0.3);
  color: var(--text-primary);
}