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

/* Color palette using CSS variables for easy tweaks */
:root {
  --color-bg: #0a192f;
  --color-card: #112240;
  --color-accent: #64ffda;
  --color-text-primary: #e6f1ff;
  --color-text-secondary: #8892b0;
  --color-button-bg: #112240;
  --color-button-hover: #0a192f;
}

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.6;
}

header {
  text-align: center;
  padding: 4rem 1rem;
  background: linear-gradient(135deg, #0f2537 0%, #112e42 100%);
}

header h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
  color: var(--color-accent);
}

header p {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
}

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem;
}

/* Card styles for sections */
.card {
  background-color: var(--color-card);
  border-radius: 8px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: 0 10px 30px -15px rgba(2, 12, 27, 0.7);
}

.card h2 {
  margin-bottom: 1rem;
  color: var(--color-accent);
}

/* Mode selection buttons */
#mode-selection {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

button {
  padding: 0.75rem 2rem;
  font-size: 1.125rem;
  border: 2px solid var(--color-accent);
  border-radius: 4px;
  background-color: transparent;
  color: var(--color-accent);
  cursor: pointer;
  transition: background-color 0.3s ease, color 0.3s ease;
}

button:hover {
  background-color: var(--color-accent);
  color: #0a192f;
}

.hidden {
  display: none;
}

label {
  display: block;
  margin-top: 1rem;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

input[type="text"],
input[type="file"] {
  width: 100%;
  padding: 0.5rem 0.75rem;
  margin-top: 0.5rem;
  border: 1px solid var(--color-accent);
  border-radius: 4px;
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  font-size: 1rem;
}

input[type="text"]::placeholder {
  color: var(--color-text-secondary);
}

code {
  display: inline-block;
  background-color: #0d253e;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  color: var(--color-accent);
  font-size: 0.9rem;
  word-break: break-all;
}

progress {
  width: 100%;
  height: 16px;
  margin-top: 1rem;
  appearance: none;
  overflow: hidden;
  border-radius: 4px;
  background-color: #223550;
}

progress::-webkit-progress-bar {
  background-color: #223550;
}

progress::-webkit-progress-value {
  background-color: var(--color-accent);
}

progress::-moz-progress-bar {
  background-color: var(--color-accent);
}

#downloadLinkContainer a {
  display: inline-block;
  margin-top: 1rem;
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
}

#downloadLinkContainer a:hover {
  text-decoration: underline;
}

/* Utility and layout classes for copy‑paste signalling UI */
.kv {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
  gap: 0.5rem;
  flex-wrap: wrap;
}
.kv span {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
}
.grid2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 1rem;
}
textarea {
  width: 100%;
  min-height: 100px;
  margin-top: 0.5rem;
  padding: 0.5rem;
  border: 1px solid var(--color-accent);
  border-radius: 4px;
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  font-family: monospace;
  resize: vertical;
}
button.btn.sm {
  padding: 0.35rem 0.75rem;
  font-size: 0.75rem;
  margin-top: 0.25rem;
  border-radius: 3px;
}
.divider {
  height: 1px;
  background-color: var(--stroke);
  margin: 1.5rem 0;
}
.progress {
  width: 100%;
  height: 8px;
  background-color: #223550;
  border-radius: 4px;
  overflow: hidden;
  margin-top: 1rem;
}
.progress div {
  height: 100%;
  width: 0;
  background-color: var(--color-accent);
  transition: width 0.2s ease;
}
.muted {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  margin-top: 0.5rem;
}
.btn.primary {
  background-color: var(--color-accent);
  color: #0a192f;
  border-color: var(--color-accent);
}
.btn.disabled {
  opacity: 0.5;
  pointer-events: none;
}