:root {
  --bg-1: #0b0013;
  --bg-2: #1a0026;
  --panel: rgba(255, 255, 255, 0.04);
  --glass-border: rgba(255, 255, 255, 0.06);
  --accent: #b47dff;
  --accent-2: #7a48ff;
  --muted: #bdb2cf;
  --white: #f6f3ff;
  --glass-shadow: 0 12px 40px rgba(8, 4, 20, 0.6);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}
html,
body {
  height: 100%;
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI",
    Roboto, "Helvetica Neue", Arial;
  background: linear-gradient(180deg, var(--bg-1), var(--bg-2));
  color: var(--white);
}
.stars {
  position: fixed;
  inset: 0;
  z-index: 0;
  display: block;
}

.topbar {
  position: relative;
  z-index: 3;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 28px;
  gap: 12px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}

.title {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.2px;
}
.subtitle {
  font-size: 13px;
  color: var(--muted);
}

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

.lang-toggle-switch {
  position: relative;
  width: 68px;
  height: 32px;
}

.lang-toggle-checkbox {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.lang-toggle-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 10px;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  cursor: pointer;
  position: relative;
  transition: background-color 0.2s ease;
}

.lang-toggle-label::after {
  content: "";
  position: absolute;
  top: 2px;
  left: 3px;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  transition: transform 0.25s ease-in-out;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.4);
}

.lang-toggle-checkbox:checked + .lang-toggle-label::after {
  transform: translateX(34px);
}

.lang-toggle-label span {
  font-size: 11px;
  font-weight: 700;
  color: var(--muted);
  z-index: 1;
  transition: color 0.25s ease-in-out;
}

.lang-toggle-checkbox:not(:checked) + .lang-toggle-label .lang-label-en,
.lang-toggle-checkbox:checked + .lang-toggle-label .lang-label-id {
  color: var(--white);
}

.tiny {
  padding: 6px 9px;
  border-radius: 10px;
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(6px);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
}
.tiny:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--white);
}

.main-grid {
  position: relative;
  z-index: 3;
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 28px;
  padding: 28px;
  align-items: stretch;
  min-height: calc(100vh - 170px);
}

.panel {
  background: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0.02),
    rgba(255, 255, 255, 0.01)
  );
  border-radius: var(--radius);
  padding: 20px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}
.panel-title {
  margin: 0 0 6px 0;
  font-size: 16px;
  color: var(--white);
}

.converter-panel .field {
  display: block;
  margin-top: 12px;
}
.field-label {
  display: block;
  margin-bottom: 8px;
  font-size: 13px;
  color: var(--muted);
}
input {
  width: 100%;
  padding: 16px 14px;
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.03);
  background: rgba(255, 255, 255, 0.02);
  color: var(--white);
  font-size: 16px;
  outline: none;
  transition: box-shadow 0.18s, transform 0.12s;
}
input::placeholder {
  color: rgba(255, 255, 255, 0.25);
}
input:focus {
  box-shadow: 0 8px 30px rgba(124, 58, 237, 0.06);
  transform: translateY(-3px);
  background: rgba(255, 255, 255, 0.03);
}
.footer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 16px;
}
.note {
  color: var(--muted);
  font-size: 13px;
  padding-right: 12px;
}
.btn-secondary {
  padding: 8px 12px;
  border-radius: 10px;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.04);
  color: var(--muted);
  cursor: pointer;
  white-space: nowrap;
}

.explanation-panel {
  display: flex;
  flex-direction: column;
  gap: 12px;
  overflow: hidden;
}
.explain-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}
.status {
  display: flex;
  gap: 8px;
  align-items: center;
}
.lang-badge {
  font-size: 12px;
  padding: 6px 8px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
}

.loader {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 3px solid rgba(255, 255, 255, 0.06);
  border-top-color: var(--accent);
  animation: spin 1s linear infinite;
}
.hidden {
  display: none;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.explain-content {
  flex-grow: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 12px;
  border-radius: 10px;
  background: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0.01),
    rgba(0, 0, 0, 0.02)
  );
  border: 1px solid rgba(255, 255, 255, 0.02);
  color: #efe9ff;
  line-height: 1.6;
  white-space: pre-wrap;
  word-wrap: break-word;
}
.explain-content .line {
  margin: 6px 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, monospace;
  font-size: 14px;
}
.explain-content .heading {
  font-weight: 700;
  margin-bottom: 8px;
}

.char {
  display: inline-block;
}
.cursor {
  display: inline-block;
  width: 10px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  margin-left: 8px;
  border-radius: 3px;
  animation: blink 1s steps(1) infinite;
  vertical-align: middle;
  height: 14px;
}
@keyframes blink {
  50% {
    opacity: 0;
  }
}

.footer {
  position: relative;
  z-index: 3;
  text-align: center;
  padding: 18px;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 920px) {
  .main-grid {
    grid-template-columns: 1fr 360px;
  }
}

@media (max-width: 800px) {
  .main-grid {
    grid-template-columns: 1fr;
    padding: 18px;
  }
  .explanation-panel {
    order: 2;
  }
  .converter-panel {
    order: 1;
  }
}

@media (max-width: 400px) {
  .topbar {
    flex-wrap: wrap;
  }
}

.explain-content::-webkit-scrollbar {
  width: 10px;
}
.explain-content::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  border-radius: 10px;
}
.lang-selector {
  display: flex;
  border: 1px solid #4a4a4a;
  border-radius: 20px;
  background-color: #222;
  overflow: hidden;
}

.lang-option {
  background-color: transparent;
  border: none;
  padding: 8px 24px;
  cursor: pointer;
  color: #999;
  font-size: 16px;
  font-weight: bold;
  transition: all 0.3s ease;
}

.lang-option.active {
  background-color: #5f3dc4;
  color: white;
}

.btn-primary {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  color: #0b0013;
  font-weight: 600;
  border: 1px solid rgba(255, 255, 255, 0.01);
  box-shadow: 0 4px 15px rgba(122, 72, 255, 0.1);
}
.btn-primary:hover {
  color: var(--white);
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  box-shadow: 0 6px 20px rgba(122, 72, 255, 0.15);
}