*,
*::before,
*::after {
  box-sizing: border-box;
}

:root {
  --bg: #fafafa;
  --fg: #1a1a1a;
  --muted: #666;
  --border: #d0d0d0;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --surface: #fff;
  --drop-bg: #f0f4ff;
  --drop-border: #93b4f8;
  --code-bg: #f5f5f5;
  --success: #16a34a;
  --radius: 8px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f0f0f;
    --fg: #e5e5e5;
    --muted: #999;
    --border: #333;
    --accent: #60a5fa;
    --accent-hover: #93bbfd;
    --surface: #1a1a1a;
    --drop-bg: #111827;
    --drop-border: #3b5998;
    --code-bg: #1e1e1e;
    --success: #4ade80;
  }
}

html {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.5;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Hero section */
.hero {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 3rem 1rem;
  text-align: center;
}

.hero-content {
  max-width: 720px;
  margin: 0 auto;
}

.hero h1 {
  margin: 0 0 0.5rem;
  font-size: 2.5rem;
  letter-spacing: -0.02em;
}

.tagline {
  font-size: 1.25rem;
  color: var(--muted);
  margin: 0 0 0.75rem;
}

.description {
  color: var(--muted);
  margin: 0 0 1.5rem;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

.description a {
  color: var(--accent);
  text-decoration: none;
}

.description a:hover {
  text-decoration: underline;
}

.hero-links {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  border-radius: 6px;
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
  transition: background 0.15s, transform 0.1s;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: var(--fg);
  color: var(--bg);
}

.btn-primary:hover {
  background: var(--muted);
}

.btn-secondary {
  background: var(--surface);
  color: var(--fg);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: var(--drop-bg);
  border-color: var(--accent);
}

/* Main content */
main {
  max-width: 720px;
  width: 100%;
  margin: 0 auto;
  padding: 0 1rem 2rem;
  flex: 1;
}

.section {
  padding: 2rem 0;
  border-bottom: 1px solid var(--border);
}

.section:last-child {
  border-bottom: none;
}

h2 {
  font-size: 1.5rem;
  margin: 0 0 0.5rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.1rem;
  margin: 1.25rem 0 0.5rem;
}

.section-intro {
  color: var(--muted);
  margin: 0 0 1.25rem;
}

/* Drop zone */
#drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 1rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
  background: var(--surface);
}

#drop-zone:hover,
#drop-zone:focus-visible {
  border-color: var(--accent);
  background: var(--drop-bg);
  outline: none;
}

#drop-zone.drag-over {
  border-color: var(--drop-border);
  background: var(--drop-bg);
  border-style: solid;
}

.drop-zone-content svg {
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.drop-zone-content p {
  margin: 0.25rem 0;
}

.hint {
  font-size: 0.85rem;
  color: var(--muted);
}

/* Preview */
#preview-container {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.5rem;
  display: flex;
  justify-content: center;
}

#preview-canvas {
  max-width: 100%;
  max-height: 400px;
  border-radius: 4px;
}

/* Results */
.result-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  margin-bottom: 0.75rem;
}

.result-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.result-type {
  font-weight: 600;
  font-size: 0.85rem;
  background: var(--accent);
  color: #fff;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
}

.result-size {
  font-size: 0.8rem;
  color: var(--muted);
}

/* View tabs */
.view-tabs {
  display: flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 0.5rem;
  width: fit-content;
}

.view-tab {
  padding: 0.3rem 0.75rem;
  font-size: 0.8rem;
  background: var(--surface);
  border: none;
  border-right: 1px solid var(--border);
  color: var(--fg);
  cursor: pointer;
  font-family: inherit;
}

.view-tab:last-child {
  border-right: none;
}

.view-tab.active {
  background: var(--accent);
  color: #fff;
}

.view-tab:hover:not(.active) {
  background: var(--drop-bg);
}

/* Data display & code blocks */
.result-data {
  position: relative;
}

.data-content {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.75rem;
  font-family: "SF Mono", "Cascadia Code", "Fira Code", Menlo, Consolas, monospace;
  font-size: 0.85rem;
  white-space: pre-wrap;
  word-break: break-all;
  overflow-x: auto;
  max-height: 400px;
  overflow-y: auto;
  line-height: 1.6;
}

pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1rem;
  margin: 0.75rem 0;
  overflow-x: auto;
}

pre code {
  font-family: "SF Mono", "Cascadia Code", "Fira Code", Menlo, Consolas, monospace;
  font-size: 0.85rem;
  line-height: 1.6;
}

code {
  font-family: "SF Mono", "Cascadia Code", "Fira Code", Menlo, Consolas, monospace;
  font-size: 0.9em;
  background: var(--code-bg);
  padding: 0.15rem 0.35rem;
  border-radius: 4px;
}

pre code {
  background: none;
  padding: 0;
}

.copy-btn {
  position: absolute;
  top: 0.35rem;
  right: 0.35rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.25rem 0.5rem;
  font-size: 0.75rem;
  cursor: pointer;
  color: var(--fg);
  font-family: inherit;
  display: flex;
  align-items: center;
  gap: 0.3rem;
  transition: background 0.15s;
}

.copy-btn:hover {
  background: var(--drop-bg);
}

.copy-btn.copied {
  color: var(--success);
  border-color: var(--success);
}

/* Hex dump styling */
.hex-line {
  display: flex;
  gap: 0;
}

.hex-offset {
  color: var(--muted);
  min-width: 6ch;
  user-select: none;
}

.hex-bytes {
  min-width: 25ch;
  letter-spacing: 0.05em;
}

.hex-ascii {
  color: var(--muted);
}

/* No results / errors */
#no-results p,
#error-section p {
  padding: 1rem;
  border-radius: var(--radius);
  text-align: center;
}

#no-results p {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--muted);
}

#error-section p {
  background: #fef2f2;
  border: 1px solid #fca5a5;
  color: #991b1b;
}

@media (prefers-color-scheme: dark) {
  #error-section p {
    background: #2d1b1b;
    border-color: #7f1d1d;
    color: #fca5a5;
  }
}

/* Formats grid */
.formats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.format-group {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
}

.format-group h3 {
  margin: 0 0 0.5rem;
  font-size: 0.9rem;
  color: var(--accent);
}

.format-group ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.format-group li {
  font-size: 0.9rem;
  padding: 0.15rem 0;
  color: var(--fg);
}

/* Install tabs */
.install-tabs {
  display: flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin: 1rem 0;
  width: fit-content;
}

.install-tab {
  padding: 0.5rem 1.25rem;
  font-size: 0.9rem;
  background: var(--surface);
  border: none;
  border-right: 1px solid var(--border);
  color: var(--fg);
  cursor: pointer;
  font-family: inherit;
  font-weight: 500;
}

.install-tab:last-child {
  border-right: none;
}

.install-tab.active {
  background: var(--accent);
  color: #fff;
}

.install-tab:hover:not(.active) {
  background: var(--drop-bg);
}

.install-content {
  animation: fadeIn 0.2s ease-out;
}

.install-content p {
  margin: 0.75rem 0;
}

.install-content a {
  color: var(--accent);
  text-decoration: none;
}

.install-content a:hover {
  text-decoration: underline;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Footer */
footer {
  text-align: center;
  padding: 1.5rem 1rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}

footer a {
  color: var(--accent);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* Loading state */
#drop-zone.loading {
  opacity: 0.6;
  pointer-events: none;
}

/* Responsive */
@media (max-width: 480px) {
  .hero {
    padding: 2rem 1rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .tagline {
    font-size: 1.1rem;
  }

  .hero-links {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 200px;
    justify-content: center;
  }

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