/* === DESIGN TOKENS === */
:root {
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);

  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  --font-body: 'Satoshi', 'Inter', sans-serif;
  --font-display: 'General Sans', 'Satoshi', sans-serif;
}

/* Dark theme (default for music tools) */
[data-theme="dark"] {
  --color-bg:             #111113;
  --color-surface:        #19191d;
  --color-surface-2:      #202026;
  --color-surface-offset: #1d1d22;
  --color-border:         #2e2e36;
  --color-border-hover:   #3f3f4a;
  --color-text:           #e0e0e4;
  --color-text-muted:     #8e8e98;
  --color-text-faint:     #5a5a64;
  --color-primary:        #4ecdc4;
  --color-primary-dim:    #3aada5;
  --color-primary-hover:  #6ee0d8;
  --color-primary-bg:     rgba(78, 205, 196, 0.08);
  --color-primary-bg-hover: rgba(78, 205, 196, 0.14);
  --color-error:          #f06292;
  --color-error-bg:       rgba(240, 98, 146, 0.1);
  --color-success:        #66bb6a;
  --color-success-bg:     rgba(102, 187, 106, 0.1);

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.4);
}

/* Light theme */
:root:not([data-theme]), [data-theme="light"] {
  --color-bg:             #f4f4f6;
  --color-surface:        #ffffff;
  --color-surface-2:      #fafafa;
  --color-surface-offset: #f0f0f3;
  --color-border:         #d8d8de;
  --color-border-hover:   #c0c0c8;
  --color-text:           #1a1a1e;
  --color-text-muted:     #6e6e78;
  --color-text-faint:     #a0a0a8;
  --color-primary:        #0e9a92;
  --color-primary-dim:    #098880;
  --color-primary-hover:  #12b5ab;
  --color-primary-bg:     rgba(14, 154, 146, 0.06);
  --color-primary-bg-hover: rgba(14, 154, 146, 0.12);
  --color-error:          #d32f5e;
  --color-error-bg:       rgba(211, 47, 94, 0.08);
  --color-success:        #2e7d32;
  --color-success-bg:     rgba(46, 125, 50, 0.08);

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme]) {
    --color-bg:             #f4f4f6;
    --color-surface:        #ffffff;
    --color-surface-2:      #fafafa;
    --color-surface-offset: #f0f0f3;
    --color-border:         #d8d8de;
    --color-border-hover:   #c0c0c8;
    --color-text:           #1a1a1e;
    --color-text-muted:     #6e6e78;
    --color-text-faint:     #a0a0a8;
    --color-primary:        #0e9a92;
    --color-primary-dim:    #098880;
    --color-primary-hover:  #12b5ab;
    --color-primary-bg:     rgba(14, 154, 146, 0.06);
    --color-primary-bg-hover: rgba(14, 154, 146, 0.12);
    --color-error:          #d32f5e;
    --color-error-bg:       rgba(211, 47, 94, 0.08);
    --color-success:        #2e7d32;
    --color-success-bg:     rgba(46, 125, 50, 0.08);

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  }
}

/* === BASE RESET === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  display: flex;
  flex-direction: column;
}

button { cursor: pointer; background: none; border: none; font: inherit; color: inherit; }
input, select { font: inherit; color: inherit; }
a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-hover); }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* === HEADER === */
.app-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-surface);
}

.header-inner {
  max-width: 720px;
  margin: 0 auto;
  padding: var(--space-4) var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo-group {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.logo-icon { color: var(--color-primary); }

.app-title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.version-tag {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  background: var(--color-surface-offset);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  font-weight: 500;
}

/* === MAIN === */
.app-main {
  max-width: 720px;
  width: 100%;
  margin: 0 auto;
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
  flex: 1;
}

/* === CARDS === */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: opacity var(--transition-interactive), border-color var(--transition-interactive);
}

.card.disabled {
  opacity: 0.45;
  pointer-events: none;
}

.card-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--color-border);
}

.card-header h2 {
  font-family: var(--font-display);
  font-size: var(--text-base);
  font-weight: 600;
}

.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-primary-bg);
  color: var(--color-primary);
  font-size: var(--text-xs);
  font-weight: 700;
  flex-shrink: 0;
}

.card-body {
  padding: var(--space-5);
}

/* === UPLOAD ZONE === */
.upload-zone {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-10) var(--space-6);
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition-interactive), background var(--transition-interactive);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.upload-zone:hover, .upload-zone.dragover {
  border-color: var(--color-primary);
  background: var(--color-primary-bg);
}

.upload-zone svg { color: var(--color-text-muted); }
.upload-text { font-weight: 500; color: var(--color-text); }
.upload-hint { font-size: var(--text-xs); color: var(--color-text-faint); }

.file-info { margin-top: var(--space-3); }

.file-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  background: var(--color-primary-bg);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--color-primary);
}

.file-badge svg { flex-shrink: 0; color: var(--color-primary); }

.file-meta {
  color: var(--color-text-muted);
  font-size: var(--text-xs);
}

.btn-clear {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  padding: 0 var(--space-1);
  line-height: 1;
  transition: color var(--transition-interactive);
}
.btn-clear:hover { color: var(--color-error); }

/* === FORM CONTROLS === */
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

.form-row:last-child { margin-bottom: 0; }

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.form-group label {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
}

.optional {
  font-weight: 400;
  color: var(--color-text-faint);
}

select, input[type="number"] {
  appearance: none;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text);
  transition: border-color var(--transition-interactive);
  width: 100%;
}

select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12' fill='none'%3E%3Cpath d='M3 4.5L6 7.5L9 4.5' stroke='%238e8e98' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
  padding-right: var(--space-8);
}

select:hover, input[type="number"]:hover {
  border-color: var(--color-border-hover);
}

select:focus, input[type="number"]:focus {
  border-color: var(--color-primary);
  outline: none;
  box-shadow: 0 0 0 2px var(--color-primary-bg);
}

select:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.range-input-group {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.range-input-group input { flex: 1; }

.note-label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-primary-bg);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  min-width: 3em;
  text-align: center;
  white-space: nowrap;
}

/* === DATA PREVIEW === */
.data-preview {
  margin-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-4);
}

.data-preview h3 {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
}

.preview-scroll {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}

table {
  border-collapse: collapse;
  width: 100%;
  font-size: var(--text-xs);
}

th, td {
  padding: var(--space-1) var(--space-3);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}

th {
  background: var(--color-surface-offset);
  font-weight: 600;
  color: var(--color-text-muted);
  position: sticky;
  top: 0;
}

td { color: var(--color-text); }

tr:last-child td { border-bottom: none; }

/* Highlight mapped columns */
th.col-pitch, td.col-pitch { color: var(--color-primary); }
th.col-velocity, td.col-velocity { color: var(--color-primary-dim); }

/* === DURATION PREVIEW === */
.duration-preview, .scale-preview {
  margin-top: var(--space-4);
  padding: var(--space-3) var(--space-4);
  background: var(--color-surface-offset);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
}

.duration-preview strong, .scale-preview strong {
  color: var(--color-primary);
  font-weight: 600;
}

.scale-preview {
  margin-top: var(--space-2);
}

.scale-notes {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-top: var(--space-2);
}

.scale-note {
  font-size: var(--text-xs);
  font-weight: 500;
  padding: 2px 6px;
  background: var(--color-primary-bg);
  color: var(--color-primary);
  border-radius: var(--radius-sm);
  font-family: 'JetBrains Mono', monospace;
}

/* === GENERATE === */
.generate-info {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.6;
}

.btn-generate {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  background: var(--color-primary);
  color: #111;
  font-weight: 600;
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: background var(--transition-interactive), transform var(--transition-interactive);
}

.btn-generate:hover:not(:disabled) {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
}

.btn-generate:active:not(:disabled) {
  transform: translateY(0);
}

.btn-generate:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* === MESSAGES === */
.error-msg {
  margin-top: var(--space-3);
  padding: var(--space-3) var(--space-4);
  background: var(--color-error-bg);
  color: var(--color-error);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  font-weight: 500;
}

.success-msg {
  margin-top: var(--space-3);
  padding: var(--space-3) var(--space-4);
  background: var(--color-success-bg);
  color: var(--color-success);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  font-weight: 500;
}

.hidden { display: none; }

/* === FOOTER === */
.app-footer {
  max-width: 720px;
  width: 100%;
  margin: 0 auto;
  padding: var(--space-6);
  text-align: center;
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.app-footer a {
  color: var(--color-text-faint);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.app-footer a:hover { color: var(--color-primary); }

/* === RESPONSIVE === */
@media (max-width: 600px) {
  .app-main { padding: var(--space-4); gap: var(--space-4); }

  .form-row {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }

  .header-inner { padding: var(--space-3) var(--space-4); }

  .card-body { padding: var(--space-4); }

  .upload-zone { padding: var(--space-6) var(--space-4); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}