/* Kanban board design system -------------------------------------------- */

:root {
  color-scheme: light;

  /* Palette */
  --color-bg: #f5f7fb;
  --color-bg-elevated: #ffffff;
  --color-surface: #eef1f7;
  --color-surface-strong: #e3e8f2;
  --color-border: #d8deea;
  --color-border-strong: #bcc6da;
  --color-text: #16192b;
  --color-text-muted: #5c6480;
  --color-text-inverse: #ffffff;

  --color-accent: #4c5cf5;
  --color-accent-strong: #3947e0;
  --color-accent-soft: #e6e9ff;
  --color-danger: #cf2f45;
  --color-danger-soft: #fdeaee;
  --color-focus: #1f6feb;

  /* Column accents */
  --color-column-todo: #6366f1;
  --color-column-todo-soft: #eceefe;
  --color-column-in_progress: #b45309;
  --color-column-in_progress-soft: #fdf1dc;
  --color-column-done: #15803d;
  --color-column-done-soft: #e3f7ea;

  /* Priority accents */
  --color-priority-high: #cf2f45;
  --color-priority-high-soft: #fdeaee;
  --color-priority-normal: #2563eb;
  --color-priority-normal-soft: #e6efff;
  --color-priority-low: #4b5563;
  --color-priority-low-soft: #eceef2;

  /* Due-date states */
  --color-due-overdue: #b42318;
  --color-due-overdue-soft: #fee4e2;
  --color-due-today: #9a6700;
  --color-due-today-soft: #fff1cc;
  --color-due-upcoming: #175cd3;
  --color-due-upcoming-soft: #e6efff;
  --color-due-none: #475467;
  --color-due-none-soft: #eaecf0;
  --color-due-completed: #067647;
  --color-due-completed-soft: #d1fadf;

  /* Spacing scale */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;

  /* Typography scale */
  --font-sans: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  --text-xs: 0.72rem;
  --text-sm: 0.82rem;
  --text-md: 0.95rem;
  --text-lg: 1.15rem;
  --text-xl: 1.6rem;

  /* Radii, shadows, motion */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-pill: 999px;
  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06), 0 1px 3px rgba(16, 24, 40, 0.08);
  --shadow-md: 0 4px 12px rgba(16, 24, 40, 0.1);
  --shadow-lg: 0 18px 32px rgba(16, 24, 40, 0.18);
  --transition: 160ms cubic-bezier(0.2, 0, 0.2, 1);
}

[data-theme="dark"] {
  color-scheme: dark;

  --color-bg: #0f1220;
  --color-bg-elevated: #1a1f33;
  --color-surface: #161a2b;
  --color-surface-strong: #202744;
  --color-border: #2a3150;
  --color-border-strong: #3b456b;
  --color-text: #eef1fb;
  --color-text-muted: #9aa3c4;
  --color-text-inverse: #0f1220;

  --color-accent: #8b95ff;
  --color-accent-strong: #a3abff;
  --color-accent-soft: #232a4d;
  --color-danger: #ff8095;
  --color-danger-soft: #3a1d27;
  --color-focus: #8ab4ff;

  --color-column-todo: #a5b4fc;
  --color-column-todo-soft: #222a4d;
  --color-column-in_progress: #fbbf24;
  --color-column-in_progress-soft: #3a2e12;
  --color-column-done: #4ade80;
  --color-column-done-soft: #12321f;

  --color-priority-high: #ff8095;
  --color-priority-high-soft: #3a1d27;
  --color-priority-normal: #93b4ff;
  --color-priority-normal-soft: #1d2a4a;
  --color-priority-low: #b8c0d4;
  --color-priority-low-soft: #242a3d;

  --color-due-overdue: #fda29b;
  --color-due-overdue-soft: #4a1d24;
  --color-due-today: #fedf89;
  --color-due-today-soft: #44340f;
  --color-due-upcoming: #a4cafe;
  --color-due-upcoming-soft: #1d2a4a;
  --color-due-none: #c7cedd;
  --color-due-none-soft: #2a3145;
  --color-due-completed: #75e0a7;
  --color-due-completed-soft: #123d2a;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow-md: 0 6px 16px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 20px 36px rgba(0, 0, 0, 0.55);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: var(--text-md);
  line-height: 1.5;
  color: var(--color-text);
  background:
    radial-gradient(1200px 500px at 12% -8%, var(--color-accent-soft), transparent 60%),
    var(--color-bg);
}

h1, h2, h3 { margin: 0; line-height: 1.25; }

/* Header ---------------------------------------------------------------- */

.app-header {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  align-items: center;
  justify-content: space-between;
  padding: var(--space-5) var(--space-6) var(--space-4);
}

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

.brand-mark {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-accent), #8b5cf6);
  color: #fff;
  font-size: var(--text-lg);
  box-shadow: var(--shadow-md);
}

.brand h1 { font-size: var(--text-xl); letter-spacing: -0.02em; }
.brand p { margin: 0; font-size: var(--text-sm); color: var(--color-text-muted); }

[hidden] { display: none !important; }

.header-actions { display: flex; align-items: center; gap: var(--space-2); }

.user-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-pill);
  background: var(--color-surface-strong);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  max-width: 16rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Controls -------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.5rem 0.9rem;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  background: var(--color-surface-strong);
  color: var(--color-text);
  font: inherit;
  font-size: var(--text-sm);
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), border-color var(--transition);
}

.btn:hover { background: var(--color-border); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn-primary { background: var(--color-accent); color: #fff; }
.btn-primary:hover { background: var(--color-accent-strong); }

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

.btn-danger { background: var(--color-danger-soft); color: var(--color-danger); }
.btn-danger:hover { background: var(--color-danger); color: #fff; }

.btn-provider {
  width: 100%;
  padding: 0.7rem 1rem;
  background: var(--color-accent);
  color: #fff;
}

.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 30px;
  height: 30px;
  padding: 0;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-text-muted);
  font-size: var(--text-md);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

.icon-btn:hover { background: var(--color-surface-strong); color: var(--color-text); }
.icon-btn.danger:hover { background: var(--color-danger); color: #fff; }
.icon-btn svg { width: 16px; height: 16px; display: block; pointer-events: none; }

input, textarea, select {
  padding: 0.55rem 0.7rem;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  color: var(--color-text);
  font: inherit;
  font-size: var(--text-sm);
}

textarea { resize: vertical; min-height: 3.5rem; }

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

/* Composer -------------------------------------------------------------- */

.composer {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin: 0 var(--space-6) var(--space-5);
  padding: var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  box-shadow: var(--shadow-sm);
}

.composer input[name="title"] { flex: 2 1 16rem; }
.composer input[name="description"] { flex: 3 1 20rem; }

/* Teams ------------------------------------------------------------------ */

.teams-panel {
  margin: 0 var(--space-6) var(--space-5);
  padding: var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  box-shadow: var(--shadow-sm);
}

.teams-heading {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.teams-heading h2 { font-size: var(--text-lg); }
.teams-heading p, .team-item p, .team-empty {
  margin: var(--space-1) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

.team-create-form, .team-member-form {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  align-items: center;
}

.team-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: var(--space-3);
  margin-top: var(--space-4);
}

.team-empty { grid-column: 1 / -1; }

.team-item {
  padding: var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
}

.team-item h3 { font-size: var(--text-md); }
.team-member-form { margin-top: var(--space-3); }
.team-member-form input { min-width: 0; flex: 1 1 10rem; }

/* Board ----------------------------------------------------------------- */

.board {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-4);
  align-items: start;
  padding: 0 var(--space-6) var(--space-7);
}

.column {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  min-height: 12rem;
  padding: var(--space-3);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--column-accent, var(--color-accent));
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  transition: background var(--transition), border-color var(--transition);
}

.column[data-status="todo"] { --column-accent: var(--color-column-todo); --column-accent-soft: var(--color-column-todo-soft); }
.column[data-status="in_progress"] { --column-accent: var(--color-column-in_progress); --column-accent-soft: var(--color-column-in_progress-soft); }
.column[data-status="done"] { --column-accent: var(--color-column-done); --column-accent-soft: var(--color-column-done-soft); }

.column-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-1);
}

.column-header h2 {
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--column-accent);
}

.count-badge {
  margin-left: auto;
  min-width: 1.6rem;
  padding: 0 var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--column-accent-soft);
  color: var(--column-accent);
  font-size: var(--text-xs);
  font-weight: 700;
  text-align: center;
}

.cards {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  min-height: 4.5rem;
  padding: var(--space-1);
  border-radius: var(--radius-md);
  transition: background var(--transition), box-shadow var(--transition);
}

.column.drop-target .cards {
  background: var(--column-accent-soft);
  box-shadow: inset 0 0 0 2px var(--column-accent);
}

.empty-state {
  display: grid;
  place-items: center;
  min-height: 4.5rem;
  padding: var(--space-4) var(--space-3);
  border: 1px dashed var(--color-border-strong);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  text-align: center;
}

/* Cards ----------------------------------------------------------------- */

.card {
  position: relative;
  padding: var(--space-3) var(--space-3) var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--priority-color, var(--color-priority-normal));
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  box-shadow: var(--shadow-sm);
  cursor: grab;
  transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
}

.card[data-priority="high"] { --priority-color: var(--color-priority-high); }
.card[data-priority="normal"] { --priority-color: var(--color-priority-normal); }
.card[data-priority="low"] { --priority-color: var(--color-priority-low); }

.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.card:active { cursor: grabbing; }
.card.dragging { opacity: 0.45; box-shadow: var(--shadow-lg); }
.card.grabbed { box-shadow: 0 0 0 2px var(--color-focus), var(--shadow-lg); }

.card-top { display: flex; align-items: center; gap: var(--space-2); margin-bottom: var(--space-2); }
.card-actions { display: flex; gap: var(--space-1); margin-left: auto; }

.card-title { font-size: var(--text-md); font-weight: 650; overflow-wrap: anywhere; }
.card-desc {
  margin: var(--space-2) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  overflow-wrap: anywhere;
}

.card-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  margin-top: var(--space-3);
  font-size: var(--text-xs);
}

.due-status {
  display: inline-flex;
  align-items: center;
  min-height: 1.5rem;
  padding: 0.1rem 0.55rem;
  border-radius: var(--radius-pill);
  font-weight: 700;
}

.due-status[data-due-status="overdue"] { background: var(--color-due-overdue-soft); color: var(--color-due-overdue); }
.due-status[data-due-status="due-today"] { background: var(--color-due-today-soft); color: var(--color-due-today); }
.due-status[data-due-status="upcoming"] { background: var(--color-due-upcoming-soft); color: var(--color-due-upcoming); }
.due-status[data-due-status="no-due-date"] { background: var(--color-due-none-soft); color: var(--color-due-none); }
.due-status[data-due-status="completed"] { background: var(--color-due-completed-soft); color: var(--color-due-completed); }

.due-date { color: var(--color-text-muted); font-variant-numeric: tabular-nums; }

.shared-team {
  display: inline-flex;
  align-items: center;
  min-height: 1.5rem;
  padding: 0.1rem 0.55rem;
  border-radius: var(--radius-pill);
  background: var(--color-accent-soft);
  color: var(--color-accent-strong);
  font-weight: 700;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 0.1rem 0.55rem;
  border-radius: var(--radius-pill);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.pill[data-priority="high"] { background: var(--color-priority-high-soft); color: var(--color-priority-high); }
.pill[data-priority="normal"] { background: var(--color-priority-normal-soft); color: var(--color-priority-normal); }
.pill[data-priority="low"] { background: var(--color-priority-low-soft); color: var(--color-priority-low); }

.drop-placeholder {
  height: 3rem;
  border: 2px dashed var(--column-accent, var(--color-accent));
  border-radius: var(--radius-md);
  background: var(--column-accent-soft, var(--color-accent-soft));
}

.card-edit { display: flex; flex-direction: column; gap: var(--space-2); }
.card-edit-row { display: flex; gap: var(--space-2); align-items: center; }
.card-edit-row .btn { flex: 0 0 auto; }

.card-hint {
  margin-top: var(--space-2);
  color: var(--color-text-muted);
  font-size: var(--text-xs);
}

/* Utility --------------------------------------------------------------- */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.toast {
  position: fixed;
  left: 50%;
  bottom: var(--space-5);
  transform: translateX(-50%);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  background: var(--color-text);
  color: var(--color-text-inverse);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-lg);
}

.toast[hidden] { display: none; }
.toast.error { background: var(--color-danger); color: #fff; }

.help-bar {
  margin: 0 var(--space-6) var(--space-5);
  color: var(--color-text-muted);
  font-size: var(--text-xs);
}

kbd {
  padding: 0.05rem 0.35rem;
  border: 1px solid var(--color-border-strong);
  border-bottom-width: 2px;
  border-radius: var(--radius-sm);
  background: var(--color-surface-strong);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.95em;
}

/* Login screen ---------------------------------------------------------- */

.login-page { display: grid; place-items: center; min-height: 100vh; padding: var(--space-5); }

.login-card {
  width: min(24rem, 100%);
  padding: var(--space-6);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  box-shadow: var(--shadow-lg);
  text-align: center;
}

.login-mark { font-size: 2.5rem; color: var(--color-accent); }
.login-lead { color: var(--color-text-muted); }
.login-actions { display: flex; flex-direction: column; gap: var(--space-2); margin: var(--space-5) 0 var(--space-4); }
.login-note { color: var(--color-text-muted); font-size: var(--text-xs); }
.login-error {
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  background: var(--color-danger-soft);
  color: var(--color-danger);
  font-size: var(--text-sm);
}

/* Responsive ------------------------------------------------------------ */

@media (max-width: 960px) {
  .board { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .app-header { padding: var(--space-4) var(--space-4) var(--space-3); }
  .composer, .help-bar { margin-inline: var(--space-4); }
  .teams-panel { margin-inline: var(--space-4); }
  .board {
    grid-template-columns: minmax(0, 1fr);
    padding: 0 var(--space-4) var(--space-6);
  }
  .composer input, .composer select, .composer .btn { flex: 1 1 100%; }
  .team-create-form, .team-member-form { width: 100%; }
  .team-create-form input, .team-create-form .btn, .team-member-form input, .team-member-form .btn { flex: 1 1 100%; }
  .user-chip { max-width: 100%; }
  .card-edit-row { flex-wrap: wrap; }
  .card-edit-row input, .card-edit-row select { flex: 1 1 8rem; }
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .card:hover { transform: none; }
}