@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=Space+Grotesk:wght@700;800&display=swap');

:root {
  --bg: #f1f5f9;
  --bg-card: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;
  --primary: #ffc451;
  --border: #e2e8f0;
  --radius: 0.75rem;
  --col-bg: #f8fafc;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1117;
    --bg-card: #1a1d27;
    --text: #f1f1f1;
    --text-muted: #9ca3af;
    --border: #2a2d3e;
    --col-bg: #13151f;
  }
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', sans-serif;
  margin: 0;
  min-height: 100vh;
}

/* Back to Main */
.back-to-main {
  display: inline-flex;
  align-items: center;
  gap: .375rem;
  padding: .375rem .875rem;
  border: 1.5px solid rgba(255,196,81,0.3);
  border-radius: .5rem;
  font-size: .8125rem;
  font-weight: 600;
  color: #ffc451;
  background: rgba(255,196,81,0.08);
  text-decoration: none;
  transition: all .2s;
  white-space: nowrap;
}
.back-to-main:hover { background: #ffc451; color: #000; }

/* Header */
.header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
  gap: 1rem;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.header-title-group h1 {
  font-size: 1rem;
  font-weight: 800;
  margin: 0 0 0.1rem;
  color: var(--text);
}

.header-title-group p {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin: 0;
}

.header-center {
  flex: 1;
  max-width: 320px;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* Search Input */
.search-input-board {
  width: 100%;
  padding: 0.45rem 0.875rem;
  border: 1.5px solid var(--border);
  border-radius: 0.5rem;
  background: var(--bg);
  color: var(--text);
  font-size: 0.8rem;
  font-family: 'Inter', sans-serif;
  outline: none;
  transition: border-color 0.15s;
}

.search-input-board:focus {
  border-color: var(--primary);
}

.search-input-board::placeholder {
  color: var(--text-muted);
}

/* Filter Bar */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.5rem;
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.3rem 0.875rem;
  border: 1.5px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  font-family: 'Inter', sans-serif;
  transition: all 0.15s;
}

.filter-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.filter-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #000;
}

/* Board Stats Bar */
.board-stats-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem 1.5rem;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted);
}

.board-stat-item {
  white-space: nowrap;
}

.board-stat-sep {
  color: var(--border);
}

.overdue-stat {
  color: #ef4444;
}

.btn-add {
  background: var(--primary);
  color: #000;
  border: none;
  border-radius: 0.5rem;
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
  font-weight: 700;
  cursor: pointer;
  font-family: 'Inter', sans-serif;
  transition: background 0.15s, transform 0.1s;
  white-space: nowrap;
}

.btn-add:hover {
  background: #e6b048;
  transform: translateY(-1px);
}

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

/* Board */
.board {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  padding: 1.5rem;
  min-height: calc(100vh - 140px);
  align-items: start;
}

/* Column */
.column {
  background: var(--col-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  min-height: 400px;
  transition: border-color 0.15s, background 0.15s;
}

.column.drag-over {
  border-color: var(--primary);
  background: rgba(255, 196, 81, 0.05);
}

.col-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
}

.col-title {
  font-size: 0.8rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text);
}

.col-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.col-count {
  background: var(--border);
  border-radius: 999px;
  padding: 0.1rem 0.5rem;
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--text-muted);
}

.col-add {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 1rem;
  padding: 0.25rem;
  transition: color 0.15s;
  line-height: 1;
}

.col-add:hover {
  color: var(--primary);
}

/* Card */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 0.875rem;
  margin-bottom: 0.625rem;
  cursor: grab;
  transition: box-shadow 0.15s, transform 0.15s, border-color 0.15s;
  border-bottom: 3px solid transparent;
  user-select: none;
  position: relative;
}

.card:last-child {
  margin-bottom: 0;
}

.card:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  transform: translateY(-1px);
}

.card:active {
  cursor: grabbing;
  box-shadow: 0 8px 24px rgba(0,0,0,0.15);
}

.card.dragging {
  opacity: 0.4;
  transform: rotate(2deg);
  box-shadow: 0 12px 32px rgba(0,0,0,0.2);
}

.card.high    { border-bottom-color: #ef4444; }
.card.medium  { border-bottom-color: #ffc451; }
.card.low     { border-bottom-color: #34d399; }

/* Overdue card */
.card.overdue {
  border-left: 3px solid #ef4444;
}

.card-title {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.375rem;
  line-height: 1.4;
}

.card-desc {
  font-size: 0.72rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 0.625rem;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.25rem;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  flex-wrap: wrap;
}

.priority-badge {
  font-size: 0.62rem;
  font-weight: 700;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.priority-badge.high   { background: rgba(239,68,68,0.1);   color: #ef4444; }
.priority-badge.medium { background: rgba(255,196,81,0.15); color: #b8860b; }
.priority-badge.low    { background: rgba(52,211,153,0.1);  color: #10b981; }

.due-date {
  font-size: 0.62rem;
  color: var(--text-muted);
  font-weight: 500;
}

.due-date.overdue-date {
  color: #ef4444;
  font-weight: 700;
}

.card-actions {
  display: flex;
  gap: 0.25rem;
}

.card-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.75rem;
  padding: 0.2rem 0.3rem;
  transition: color 0.15s;
  border-radius: 0.25rem;
}

.card-btn:hover        { color: var(--primary); background: rgba(255,196,81,0.1); }
.card-btn.delete:hover { color: #ef4444; background: rgba(239,68,68,0.1); }

/* Drop zone indicator */
.drop-placeholder {
  border: 2px dashed rgba(255,196,81,0.4);
  border-radius: 0.5rem;
  height: 60px;
  margin-bottom: 0.625rem;
  background: rgba(255,196,81,0.03);
}

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
  backdrop-filter: blur(2px);
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: all;
}

.modal {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 1.5rem;
  width: 100%;
  max-width: 440px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
  transform: scale(0.95);
  transition: transform 0.2s;
  border: 1px solid var(--border);
}

.modal-overlay.open .modal {
  transform: scale(1);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.25rem;
}

.modal h2 {
  font-size: 0.95rem;
  font-weight: 700;
  margin: 0;
  color: var(--text);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 1.1rem;
  padding: 0.2rem;
  transition: color 0.15s;
  line-height: 1;
}

.modal-close:hover {
  color: var(--text);
}

.form-group {
  margin-bottom: 0.875rem;
}

.form-group label {
  display: block;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 0.625rem 0.75rem;
  border: 1.5px solid var(--border);
  border-radius: 0.5rem;
  background: var(--bg-card);
  color: var(--text);
  font-size: 0.82rem;
  box-sizing: border-box;
  outline: none;
  transition: border-color 0.15s;
  font-family: 'Inter', sans-serif;
  -webkit-appearance: none;
  appearance: none;
}

.form-group textarea {
  resize: vertical;
  min-height: 80px;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--primary);
}

.modal-btns {
  display: flex;
  gap: 0.5rem;
  justify-content: flex-end;
  margin-top: 1.25rem;
}

.btn-cancel {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.8rem;
  cursor: pointer;
  font-family: 'Inter', sans-serif;
  transition: border-color 0.15s;
}

.btn-cancel:hover {
  border-color: var(--text-muted);
}

.btn-save {
  padding: 0.5rem 1.25rem;
  background: var(--primary);
  color: #000;
  border: none;
  border-radius: 0.5rem;
  font-size: 0.8rem;
  font-weight: 700;
  cursor: pointer;
  font-family: 'Inter', sans-serif;
  transition: background 0.15s;
}

.btn-save:hover {
  background: #e6b048;
}

/* Empty column state */
.col-empty {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--text-muted);
  font-size: 0.72rem;
  border: 2px dashed var(--border);
  border-radius: 0.5rem;
}

/* Toast */
.toast {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  background: #1a1d27;
  color: #f1f1f1;
  border: 1px solid #2a2d3e;
  border-radius: var(--radius);
  padding: 0.75rem 1.25rem;
  font-size: 0.8rem;
  font-weight: 600;
  z-index: 9999;
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
  opacity: 0;
  transform: translateY(8px);
  transition: all 0.3s ease;
  pointer-events: none;
}

.toast.show {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 900px) {
  .board { grid-template-columns: repeat(2, 1fr); }
  .header-center { display: none; }
  .header { padding: 0.75rem 1rem; gap: 0.5rem; flex-wrap: wrap; }
  .header-right { gap: 0.5rem; }
  .filter-bar { gap: 0.375rem; padding: 0.5rem 1rem; overflow-x: auto; }
  .board-stats-bar { padding: 0.375rem 1rem; font-size: 0.72rem; flex-wrap: wrap; gap: 0.5rem; }
}

@media (max-width: 600px) {
  .board { grid-template-columns: 1fr; padding: 0.75rem; gap: 0.75rem; }
  .header { flex-wrap: wrap; }
  .header-title-group h1 { font-size: 1rem; }
  .header-title-group p  { display: none; }
  .btn-add { padding: 0.4rem 0.75rem; font-size: 0.78rem; }
  .back-to-main { font-size: 0.72rem; padding: 0.3rem 0.625rem; }
  .filter-btn { padding: 0.3rem 0.625rem; font-size: 0.72rem; }
  .column { border-radius: 0.625rem; }
  .card-list { gap: 0.5rem; }
  .card { padding: 0.875rem; }
  .modal { width: 95vw; padding: 1.25rem; }
}

@media (max-width: 380px) {
  .header-right { gap: 0.375rem; }
  .back-to-main { display: none; }
  .board-stats-bar .board-stat-sep { display: none; }
}