/* ============================================================
   Music Practice Tracker — styles
   Dependency-free. Light + dark via prefers-color-scheme.
   ============================================================ */

/* ---- Theme tokens ---------------------------------------- */
:root {
  --bg:            #f2f4f8;
  --surface:       #ffffff;
  --surface-alt:   #f0f2f6;
  --text:          #1c2430;
  --text-muted:    #5c6675;
  --border:        #d5dae2;
  --border-strong: #b9c1cd;

  --primary:       #4f46e5;
  --primary-hover: #4338ca;
  --primary-text:  #ffffff;

  --danger:        #dc2626;
  --danger-hover:  #b91c1c;

  --focus-ring:    #4f46e5;
  --shadow:        0 1px 2px rgba(20, 30, 50, .06),
                   0 6px 20px rgba(20, 30, 50, .08);

  --radius:        10px;
  --radius-sm:     7px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:            #14151b;
    --surface:       #1d1f28;
    --surface-alt:   #262935;
    --text:          #e7eaf0;
    --text-muted:    #9aa4b4;
    --border:        #333747;
    --border-strong: #454a5d;

    --primary:       #6366f1;
    --primary-hover: #7c7ff5;
    --primary-text:  #ffffff;

    --danger:        #f87171;
    --danger-hover:  #ef4444;

    --focus-ring:    #818cf8;
    --shadow:        0 1px 2px rgba(0, 0, 0, .3),
                     0 6px 22px rgba(0, 0, 0, .4);
  }
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  padding: 1.5rem 1rem 4rem;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
  /* Never let the page scroll sideways on mobile. */
  overflow-x: hidden;
}

.app {
  max-width: 760px;
  margin: 0 auto;
}

/* ---- Header ----------------------------------------------- */
.app-header { margin-bottom: 1.5rem; }

h1 {
  margin: 0 0 .25rem;
  font-size: clamp(1.5rem, 4vw, 2rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.tagline {
  margin: 0;
  color: var(--text-muted);
  font-size: .95rem;
}

/* ---- Form ------------------------------------------------- */
.practice-form {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

/* Smart inputs wrap to one column on narrow screens. */
.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  min-width: 0; /* allow inputs to shrink instead of overflowing */
}

label {
  font-size: .85rem;
  font-weight: 600;
  color: var(--text-muted);
}

input[type="text"],
input[type="number"],
textarea {
  width: 100%;
  font: inherit;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: .55rem .65rem;
  transition: border-color .12s ease, box-shadow .12s ease;
}

input::placeholder,
textarea::placeholder { color: var(--text-muted); opacity: .8; }

input:focus-visible,
textarea:focus-visible {
  outline: none;
  border-color: var(--focus-ring);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--focus-ring) 30%, transparent);
}

/* Exercise Number Range group */
.range-group {
  margin: 0;
  padding: .9rem 1rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-alt);
}

.range-group legend {
  padding: 0 .4rem;
  font-size: .85rem;
  font-weight: 700;
  color: var(--text-muted);
}

.range-fields {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.range-fields .field { flex: 1 1 130px; }

/* ---- Buttons ---------------------------------------------- */
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

.btn {
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  padding: .6rem 1.1rem;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: background-color .12s ease, border-color .12s ease,
              color .12s ease, transform .04s ease;
}

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

.btn:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--focus-ring) 40%, transparent);
}

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

.btn-secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border-strong);
}
.btn-secondary:hover { background: var(--surface-alt); }

.btn-danger {
  background: transparent;
  color: var(--danger);
  border-color: var(--danger);
}
.btn-danger:hover {
  background: var(--danger);
  color: var(--primary-text);
}

/* ---- Progress + results ----------------------------------- */
.results { margin-top: 1.5rem; }

.progress-counter {
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: .75rem;
  min-height: 1.25em; /* reserve space so layout doesn't jump when filled */
}
.progress-counter:empty { margin-bottom: 0; }

.exercise-list {
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

/* ============================================================
   Exercise rows — built at runtime by app.js (NOT in the HTML).
   For each exercise app.js creates:

     <div class="exercise-row">
       <input type="checkbox" class="ex-check">          completion toggle
       <span class="ex-name"></span>                     e.g. "Exercise 12"
       <input type="text" class="ex-oneline">            comment (see below)
       <button type="button" class="ex-details">Edit</button>
     </div>

   app.js toggles the `.completed` modifier class on `.exercise-row`
   to strike through + dim the name. `.ex-oneline` is directly editable
   when the comment is a single line (or empty); typing there persists via
   the same throttle as the modal. It becomes `[readonly]` (greyed out,
   click-to-open) once the comment has a second line, since only the
   modal's textarea can hold multi-line text.
   ============================================================ */
.exercise-row {
  display: flex;
  align-items: center;
  gap: .7rem;
  padding: .55rem .7rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
}

.ex-check {
  flex: 0 0 auto;
  width: 1.15rem;
  height: 1.15rem;
  accent-color: var(--primary);
  cursor: pointer;
}

.ex-name {
  flex: 0 0 auto;
  font-weight: 600;
  white-space: nowrap;
}

/* Comment box: editable in place for single-line comments (normal input
   look). When locked (multi-line comment), the [readonly] rule below makes
   it look non-editable and clickable (opens the modal) with a pointer
   cursor. */
.ex-oneline {
  flex: 1 1 auto;
  min-width: 0;               /* lets it shrink so the row never overflows */
  text-overflow: ellipsis;
}
.ex-oneline[readonly] {
  background: var(--surface-alt);
  color: var(--text-muted);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
}
.ex-oneline[readonly]:hover {
  border-color: var(--border-strong);
  color: var(--text);
}
.ex-oneline[readonly]:empty::before,
.ex-oneline[readonly][value=""] { font-style: italic; }

.ex-details {
  flex: 0 0 auto;
  font: inherit;
  font-weight: 600;
  font-size: .9rem;
  cursor: pointer;
  padding: .4rem .75rem;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  transition: background-color .12s ease;
}
.ex-details:hover { background: var(--surface-alt); }
.ex-details:focus-visible,
.ex-check:focus-visible,
.ex-oneline:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--focus-ring) 40%, transparent);
}

/* Completed state: strike through + dim the exercise name. */
.exercise-row.completed .ex-name {
  text-decoration: line-through;
  color: var(--text-muted);
  opacity: .7;
}
.exercise-row.completed { background: var(--surface-alt); }

/* ---- Details modal (native <dialog>) ---------------------- */
.details-modal {
  width: min(92vw, 560px);
  max-height: 90vh;
  padding: 1.5rem;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 12px 48px rgba(0, 0, 0, .35);
}

.details-modal::backdrop {
  background: rgba(15, 20, 30, .55);
  backdrop-filter: blur(2px);
}

#modal-title {
  margin: 0 0 1rem;
  font-size: 1.25rem;
  line-height: 1.25;
}

.modal-completed {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  margin-bottom: 1rem;
}
.modal-completed #modal-check {
  width: 1.15rem;
  height: 1.15rem;
  accent-color: var(--primary);
  cursor: pointer;
}

.modal-comment-label { display: block; margin-bottom: .35rem; }

#modal-comment {
  width: 100%;
  min-height: 9rem;
  resize: vertical;
  line-height: 1.5;
}

.modal-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: .75rem;
  margin-top: 1.25rem;
}

/* ---- Motion preference ------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}