/* =========================================
   Root Variables
========================================= */
:root {
  color-scheme: light dark;
  --bg: #050712;
  --card-bg: rgba(10, 10, 20, 0.96);
  --card-border: rgba(255, 255, 255, 0.06);
  --accent: #10b981;
  --accent-soft: rgba(16, 185, 129, 0.12);
  --accent-strong: #22c55e;
  --error: #f97373;
  --text-main: #e5e7eb;
  --text-muted: #9ca3af;
  --chip-bg: rgba(55, 65, 81, 0.7);

  --start-color: #2779bd;
  --target-color: #c53030;
  --path-color: #22c55e;
  --neighbor-color: #9ca3af;
}

/* =========================================
   Base
========================================= */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  color: var(--text-main);

  background:
    radial-gradient(circle at 10% 10%, #111827 0, transparent 50%),
    radial-gradient(circle at 90% 90%, #111827 0, transparent 55%),
    radial-gradient(circle at 20% 80%, #0f766e 0, transparent 45%),
    var(--bg);

  padding: 2rem;
  display: flex;
  justify-content: center;
}

.page {
  width: 100%;
  max-width: 1400px;
}

/* =========================================
   Header
========================================= */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

h1 {
  margin: 0;
  font-size: 1.8rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.logo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, #ffffff, var(--accent));
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.9);
}
.search-ticker {
  min-height: 20px;   /* forces it to occupy space */
  display: block;
}
.header-subtitle {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.header-left {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.header-badges {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}

.badge {
  padding: 0.12rem 0.5rem;
  border-radius: 999px;
  font-size: 0.7rem;
  background: rgba(31, 41, 55, 0.7);
  border: 1px solid rgba(75, 85, 99, 0.9);
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.badge-accent {
  background: var(--accent-soft);
  border-color: rgba(16, 185, 129, 0.4);
  color: var(--accent-strong);
}

.actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

#searchTicker,
#searchWarning {
  opacity: 0;
  transition: opacity 0.35s ease-in-out;
}

#searchTicker.visible,
#searchWarning.visible {
  opacity: 1;
  transition: opacity 0.35s ease-in-out;
}


.error-box {
  background: #3b0c0c;
  color: #ffbaba;
  border: 1px solid #b00000;
  padding: 10px 14px;
  border-radius: 6px;
  white-space: pre-wrap;
}

.info-box {
  background: #0c1f3b;
  color: #d0e5ff;
  padding: 10px 14px;
  border-radius: 6px;
  margin-bottom: 8px;
}

#spinner {
  opacity: 0;
  transition: opacity 0.25s ease-in-out;
}

#spinner.visible {
  opacity: 1;
}



/* =========================================
   Buttons
========================================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 0.85rem;
  border-radius: 999px;
  text-decoration: none;
  cursor: pointer;
  font-size: 0.85rem;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(15, 23, 42, 0.9);
  color: var(--text-main);
  transition: 0.15s ease;
  backdrop-filter: blur(10px);
}


.btn:hover {
  background: rgba(31, 41, 55, 0.9);
  transform: translateY(-1px);
  border-color: rgba(148, 163, 184, 0.5);
}

.btn-primary {
  background: linear-gradient(135deg, #22c55e, #0ea5e9);
  color: #0b1120;
  border: none;
  font-weight: 600;
  box-shadow: 0 6px 18px rgba(45, 212, 191, 0.4);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #4ade80, #38bdf8);
  box-shadow: 0 10px 24px rgba(45, 212, 191, 0.55);
}

.btn-ghost {
  background: transparent;
  border: 1px solid rgba(148, 163, 184, 0.35);
  color: var(--text-muted);
}

.btn-ghost:hover {
  background: rgba(15, 23, 42, 0.85);
  color: var(--text-main);
}

/* =========================================
   Cards & Layout
========================================= */
.layout {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 1.5rem;
}

@media (max-width: 900px) {
  .layout {
    grid-template-columns: 1fr;
  }
}

.card {
  background: var(--card-bg);
  border-radius: 18px;
  border: 1px solid var(--card-border);
  padding: 1.25rem;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(18px);
}

.card-title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 600;
}

.card-subtitle {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 0.9rem;
}

/* =========================================
   Form
========================================= */
.row {
  display: grid;
  gap: 0.75rem;
}

@media (min-width: 700px) {
  .row {
    grid-template-columns: 1fr 1fr;
  }
}

input[type="text"],
input[type="number"],
#startArtist,
#targetArtist,
#playlistName {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.7);
  background: rgba(15, 23, 42, 0.9);
  font-size: 0.88rem;
  color: var(--text-main);
}

input:focus {
  border-color: rgba(45, 212, 191, 0.8);
  box-shadow: 0 0 0 1px rgba(45, 212, 191, 0.75);
}

.muted {
  color: var(--text-muted);
  font-size: 0.78rem;

  display: block;
  width: 100%;
}

/* =========================================
   Autocomplete
========================================= */
.autocomplete-container {
  position: relative;
}

.autocomplete-list {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  right: 0;
  display: none;
  max-height: 260px;
  overflow-y: auto;
  background: rgba(15, 23, 42, 0.98);
  border-radius: 14px;
  border: 1px solid rgba(55, 65, 81, 0.9);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
  z-index: 50;
}

.autocomplete-item {
  padding: 0.42rem 0.55rem;
  border-radius: 10px;
  font-size: 0.86rem;
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
  cursor: pointer;
}

.autocomplete-item:hover,
.autocomplete-item[aria-selected="true"] {
  background: rgba(31, 41, 55, 0.95);
}

/* =========================================
   Graph
========================================= */
#graph-card {
  padding: 0.7rem;
  position: relative;
}

#graph {
  height: min(82vh, 880px);
  width: 100%;
  border-radius: 16px;
  border: 1px solid rgba(55, 65, 81, 0.9);
  background: #202436;
  overflow: hidden;
}

#edge-tooltip {
  position: absolute;
  display: none;
  background: rgba(15, 23, 42, 0.98);
  border: 1px solid rgba(55, 65, 81, 0.95);
  padding: 6px;
  border-radius: 12px;
  pointer-events: none;
  z-index: 999;
  max-width: 260px;
}

#edge-tooltip img {
  width: 110px;
  height: 110px;
  border-radius: 10px;
  object-fit: cover;
  display: block;
  margin: auto;
}

/* Graph Controls */
#graph-controls {
  display: flex;
  justify-content: space-between;
  margin-top: 0.75rem;
  gap: 1rem;
  width: 100%;
}

.graph-controls-left,
.graph-controls-right {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex: 1;
}

/* Jump Dropdown */
#nodeSelect {
  padding: 0.45rem 0.7rem;
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.7);
  background: rgba(15, 23, 42, 0.95);
  color: var(--text-main);
  width: 330px;
}

/* Legend */
.legend-item {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.18rem 0.45rem;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(55, 65, 81, 0.9);
  font-size: 0.7rem;
  color: var(--text-muted);
}

.legend-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.legend-start { background: var(--start-color); }
.legend-target { background: var(--target-color); }
.legend-path { background: var(--path-color); }
.legend-neighbor { background: var(--neighbor-color); }


/*
For Maching Learning
*/

.coming-soon-container {
  max-width: 900px;
  margin: 4rem auto;
  text-align: center;
  padding: 2rem;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 10px;
}

.coming-soon-container h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.donation-msg {
  margin-top: 0.5rem;
  font-size: 1.2rem;
  opacity: 0.85;
}

.coming-img-wrapper {
  margin-top: 2rem;
}

.coming-img {
  max-width: 400px;
  width: 100%;
  border-radius: 10px;
  opacity: 0.9;
  border: 1px solid var(--card-border);
}

.arrow-wrapper {
  margin-top: 2rem;
  font-size: 2rem;
  color: var(--accent);
  user-select: none;
}

.arrow {
  font-size: 3rem;
  animation: bounce 1.4s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(8px); }
}

.arrow-text {
  margin-top: 0.5rem;
  font-size: 1rem;
}