:root {
  --bg: #0f1728;
  --card: rgba(20, 33, 56, 0.9);
  --ink: #eaf2ff;
  --ink-dim: #9cb0d4;
  --stroke: rgba(156, 176, 212, 0.28);
  --ok: #33d194;
  --err: #ff7a7a;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--ink);
  background: radial-gradient(1200px 520px at 10% -8%, #223b65 0%, var(--bg) 60%), var(--bg);
}

.app {
  max-width: 1320px;
  margin: 0 auto;
  padding: 22px;
  display: grid;
  grid-template-columns: 480px 1fr;
  gap: 16px;
}

.panel {
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: 18px;
  backdrop-filter: blur(5px);
}

.controls,
.helper {
  padding: 18px;
  display: grid;
  gap: 12px;
  align-content: start;
}

.header-row {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.lang-picker {
  min-width: 160px;
}

h1,
h2,
h3 {
  margin: 0;
}

h1 {
  font-size: 42px;
  line-height: 1.08;
}

h2 {
  font-size: 38px;
  line-height: 1.08;
}

h3 {
  font-size: 24px;
}

.sub {
  margin: 0;
  font-size: 17px;
  color: var(--ink-dim);
}

label {
  display: grid;
  gap: 6px;
  color: var(--ink-dim);
  font-size: 16px;
}

input,
select,
button {
  width: 100%;
  border-radius: 12px;
  border: 1px solid var(--stroke);
  background: rgba(9, 15, 27, 0.55);
  color: var(--ink);
  padding: 10px 12px;
  font-size: 24px;
}

button {
  border: none;
  font-weight: 700;
  cursor: pointer;
  background: linear-gradient(90deg, #1a8cff, #05bca8);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.grid3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.advanced {
  border: 1px solid var(--stroke);
  border-radius: 12px;
  padding: 10px;
  display: grid;
  gap: 10px;
}

.advanced > summary {
  font-weight: 700;
  cursor: pointer;
}

.instruction-list {
  margin: 0;
  padding-left: 24px;
  display: grid;
  gap: 10px;
  color: #d9e6ff;
  font-size: 20px;
  line-height: 1.5;
}

.result-card {
  border: 1px solid var(--stroke);
  border-radius: 12px;
  background: rgba(8, 12, 21, 0.45);
  padding: 12px;
}

pre {
  margin: 8px 0 0;
  padding: 10px;
  border: 1px solid var(--stroke);
  border-radius: 10px;
  background: rgba(8, 12, 21, 0.5);
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 14px;
  line-height: 1.45;
  color: #c9d7f0;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
}

code {
  background: rgba(7, 12, 21, 0.55);
  border: 1px solid var(--stroke);
  border-radius: 6px;
  padding: 1px 6px;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
}

@media (max-width: 1120px) {
  .app {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  h1 {
    font-size: 34px;
  }

  h2 {
    font-size: 30px;
  }

  .grid3 {
    grid-template-columns: 1fr;
  }

  .header-row {
    flex-direction: column;
  }
}