/* ═══════════════════════════════════════════════════════════════
   MsgPack Converter — Editorial / Magazine Style (Split View)
   ═══════════════════════════════════════════════════════════════ */

/* ── Design Tokens ── */
:root {
  /* Palette: Warm parchment & ink */
  --bg: #faf8f5;
  --bg-subtle: #f3f0eb;
  --surface: #ffffff;
  --border: #e8e4de;
  --border-light: #f0ece6;

  --ink: #1a1714;
  --ink-secondary: #6b6560;
  --ink-tertiary: #a09a93;
  --accent: #c8553d;
  --accent-hover: #b04430;
  --accent-subtle: rgba(200, 85, 61, 0.08);

  --success: #3d8b6e;
  --error: #c8553d;

  /* Typography */
  --font-serif: "Playfair Display", "Georgia", serif;
  --font-sans: "DM Sans", "Helvetica Neue", sans-serif;
  --font-mono: "JetBrains Mono", "Consolas", monospace;

  /* Scale */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.5rem;
  --text-2xl: 2rem;

  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;

  /* Transitions */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --duration: 0.4s;
  --duration-fast: 0.2s;

  /* Layout */
  --max-width: 1200px;
  --radius: 2px;
}

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

html,
body {
  height: 100%; /* Full height for single page feel */
  overflow-x: hidden;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  color: var(--ink);
  background-color: var(--bg);
  display: flex;
  flex-direction: column;
}

::selection {
  background-color: var(--accent-subtle);
  color: var(--ink);
}

/* ═══════════════════════════════════════════════════════════════
   COMPACT HEADER
   ═══════════════════════════════════════════════════════════════ */
.compact-header {
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  flex-shrink: 0;
  animation: fadeIn 0.8s var(--ease-out) both;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-title {
  font-family: var(--font-serif);
  font-size: var(--text-xl);
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.title-light {
  font-weight: 400;
  font-style: italic;
  color: var(--ink-secondary);
  font-size: 0.9em;
}

/* ── Header Actions ── */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.github-link {
  color: var(--ink);
  opacity: 0.6;
  transition:
    opacity 0.2s ease,
    transform 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.github-link:hover {
  opacity: 1;
  transform: translateY(-1px);
}

.star-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 6px 12px;
  border-radius: 100px; /* Pill shape */
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 500;
  color: var(--ink);
  text-decoration: none;
  transition: all 0.2s ease;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.03);
}

.star-btn svg {
  color: var(--ink-secondary);
  transition:
    color 0.2s ease,
    fill 0.2s ease;
}

.star-btn:hover {
  border-color: var(--ink-secondary);
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
  transform: translateY(-1px);
}

.star-btn:hover svg {
  fill: #e3b341;
  color: #e3b341;
}

/* ═══════════════════════════════════════════════════════════════
   MAIN STAGE (Split View)
   ═══════════════════════════════════════════════════════════════ */
.converter-stage {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr auto 1fr; /* MsgPack | Actions | JSON */
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
  animation: fadeInUp 0.8s var(--ease-out) 0.2s both;
  overflow: hidden; /* Avoid double scrollbars within main */
}

/* ── Panel ── */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  height: 100%;
  transition:
    border-color var(--duration) var(--ease-out),
    box-shadow var(--duration) var(--ease-out);
  overflow: hidden;
}

.panel:focus-within {
  border-color: var(--ink-tertiary);
  box-shadow: 0 0 0 3px var(--accent-subtle);
}

.panel-header {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-subtle);
  flex-shrink: 0;
}

.panel-label {
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--ink-secondary);
}

.code-textarea {
  flex: 1; /* Fill remaining height */
  padding: var(--space-md);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.6;
  color: var(--ink);
  background: transparent;
  border: none;
  outline: none;
  resize: none; /* Layout handles resizing */
}

.code-textarea::placeholder {
  color: var(--ink-tertiary);
  font-style: italic;
  opacity: 0.6;
}

.panel-footer {
  padding: var(--space-xs) var(--space-md);
  border-top: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: space-between; /* Button left, Error right (or vice versa) */
  background: var(--surface);
  min-height: 48px;
  flex-shrink: 0;
}

/* ── Actions Column ── */
.col-actions {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: var(--space-md);
  padding: var(--space-sm) 0;
}

.action-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  width: 120px;
  padding: 12px 0;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  background: var(--ink);
  color: var(--bg);
  cursor: pointer;
  transition: all var(--duration) var(--ease-out);
}

.action-btn:hover {
  background: var(--accent);
  border-color: var(--accent);
  transform: scale(1.02);
  box-shadow: 0 4px 12px rgba(200, 85, 61, 0.2);
}

.action-btn:active {
  transform: scale(0.98);
}

/* ── Format Selector ── */
.format-selector {
  display: flex;
  gap: 2px;
  background: rgba(0, 0, 0, 0.03);
  padding: 2px;
  border-radius: 2px;
}

.format-btn {
  border: none;
  background: transparent;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--ink-tertiary);
  cursor: pointer;
  border-radius: 2px;
  transition: all 0.2s ease;
}

.format-btn:hover {
  color: var(--ink);
}
.format-btn.active {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

/* ── Small Buttons ── */
.small-btn {
  border: 1px solid var(--border);
  background: transparent;
  padding: 4px 10px;
  font-size: var(--text-xs);
  color: var(--ink-tertiary);
  cursor: pointer;
  border-radius: 2px;
  transition: all 0.2s ease;
}

.small-btn:hover {
  border-color: var(--ink-secondary);
  color: var(--ink);
}

.small-btn.copied {
  border-color: var(--success);
  color: var(--success);
  background: rgba(61, 139, 110, 0.05);
}

/* ── Error Message ── */
.error-message {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--error);
  opacity: 0;
  transition: opacity 0.3s ease;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 200px;
  text-align: right;
}

.error-message.visible {
  opacity: 1;
}

/* ── Footer ── */
.site-footer {
  text-align: center;
  padding: var(--space-sm);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  font-size: var(--text-xs);
  color: var(--ink-tertiary);
}

/* ── Animations ── */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ── Responsive ── */
@media (max-width: 800px) {
  .converter-stage {
    grid-template-columns: 1fr; /* Stack vertically on mobile */
    grid-template-rows: 1fr auto 1fr;
    overflow-y: auto; /* Scroll on mobile */
  }

  .col-actions {
    flex-direction: row;
    padding: var(--space-xs) 0;
  }

  .panel {
    min-height: 300px; /* Ensure height on mobile */
  }
}