/* ============================================================
   AI STUDY PLANNER — style.css
   Theme: Midnight Navy × Amber × Editorial Typography
   ============================================================ */

/* ── CSS Variables ───────────────────────────────────────── */
:root {
  --bg:          #0a0e1a;
  --bg-card:     #111827;
  --bg-card-2:   #161d2e;
  --border:      rgba(255,255,255,0.07);
  --border-hl:   rgba(255,255,255,0.14);

  --accent:      #f5a623;
  --accent-dim:  rgba(245,166,35,0.15);
  --accent-glow: rgba(245,166,35,0.35);

  --green:       #3ecf8e;
  --green-dim:   rgba(62,207,142,0.12);
  --red:         #ef4444;
  --red-dim:     rgba(239,68,68,0.12);

  --priority-low:    #3ecf8e;
  --priority-medium: #f5a623;
  --priority-high:   #ef4444;

  --text-primary:   #f0f4ff;
  --text-secondary: #8892aa;
  --text-muted:     #4a5568;

  --font-display: 'Playfair Display', Georgia, serif;
  --font-body:    'DM Sans', system-ui, sans-serif;

  --radius:    14px;
  --radius-sm: 8px;
  --shadow:    0 4px 24px rgba(0,0,0,0.4);
  --shadow-lg: 0 12px 48px rgba(0,0,0,0.6);

  --transition: 0.22s cubic-bezier(0.4,0,0.2,1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* ── Background Orbs ─────────────────────────────────────── */
.bg-orb {
  position: fixed;
  border-radius: 50%;
  filter: blur(90px);
  pointer-events: none;
  z-index: 0;
  animation: drift 12s ease-in-out infinite alternate;
}
.orb-1 {
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(245,166,35,0.12) 0%, transparent 70%);
  top: -150px; left: -150px;
  animation-delay: 0s;
}
.orb-2 {
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(62,207,142,0.07) 0%, transparent 70%);
  bottom: -200px; right: -200px;
  animation-delay: -4s;
}
.orb-3 {
  width: 350px; height: 350px;
  background: radial-gradient(circle, rgba(99,102,241,0.08) 0%, transparent 70%);
  top: 40%; left: 55%;
  animation-delay: -8s;
}
@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to   { transform: translate(30px, 20px) scale(1.05); }
}

/* ── App Wrapper ─────────────────────────────────────────── */
.app-wrapper {
  position: relative;
  z-index: 1;
  max-width: 1240px;
  margin: 0 auto;
  padding: 36px 24px 64px;
}

/* ── Header ──────────────────────────────────────────────── */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
  flex-wrap: wrap;
  gap: 16px;
}
.header-left { display: flex; align-items: center; gap: 16px; }
.logo-mark {
  width: 52px; height: 52px;
  background: linear-gradient(135deg, var(--accent), #e08b10);
  border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 24px var(--accent-glow);
}
.logo-icon {
  font-size: 24px;
  color: #0a0e1a;
  line-height: 1;
}
.app-title {
  font-family: var(--font-display);
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 900;
  letter-spacing: -0.5px;
  color: var(--text-primary);
  line-height: 1;
}
.app-title .accent { color: var(--accent); }
.app-tagline {
  font-size: 12px;
  color: var(--text-secondary);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-top: 4px;
  font-weight: 300;
}

.header-stats { display: flex; gap: 10px; }
.stat-pill {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 10px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 40px;
  min-width: 72px;
}
.stat-pill.accent-pill {
  background: var(--accent-dim);
  border-color: rgba(245,166,35,0.25);
}
.stat-num {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
}
.accent-pill .stat-num { color: var(--accent); }
.stat-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--text-secondary);
  margin-top: 2px;
}

/* ── Progress Section ────────────────────────────────────── */
.progress-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 28px;
  position: relative;
  overflow: hidden;
}
.progress-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(245,166,35,0.03) 0%, transparent 60%);
  pointer-events: none;
}
.progress-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}
.progress-label {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--text-secondary);
}
.progress-pct {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  transition: color var(--transition);
}
.progress-track {
  width: 100%;
  height: 10px;
  background: rgba(255,255,255,0.05);
  border-radius: 100px;
  overflow: visible;
  position: relative;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #e08b10, var(--accent), #ffd166);
  border-radius: 100px;
  width: 0%;
  transition: width 0.6s cubic-bezier(0.34,1.56,0.64,1);
  position: relative;
  z-index: 1;
}
.progress-glow {
  position: absolute;
  top: 50%; left: 0;
  transform: translateY(-50%);
  height: 20px;
  background: var(--accent);
  border-radius: 100px;
  width: 0%;
  filter: blur(8px);
  opacity: 0.4;
  transition: width 0.6s cubic-bezier(0.34,1.56,0.64,1);
}
.progress-sublabel {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 10px;
  font-style: italic;
  transition: color var(--transition);
}

/* ── Main Grid ───────────────────────────────────────────── */
.main-grid {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 24px;
  align-items: start;
}
@media (max-width: 860px) {
  .main-grid { grid-template-columns: 1fr; }
}

/* ── Panel Base ──────────────────────────────────────────── */
.add-panel,
.tasks-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  position: relative;
  overflow: hidden;
}
.add-panel::after {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), #ffd166);
  border-radius: var(--radius) var(--radius) 0 0;
}
.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}
.panel-title {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}
.panel-icon {
  width: 32px; height: 32px;
  border: 1.5px solid var(--accent);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: var(--accent);
  font-size: 18px;
  font-weight: 300;
}

/* ── Form ────────────────────────────────────────────────── */
.form-group { margin-bottom: 18px; }
.form-label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin-bottom: 8px;
}
.form-input {
  width: 100%;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 14px;
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
  -webkit-appearance: none;
}
.form-input::placeholder { color: var(--text-muted); }
.form-input:focus {
  border-color: var(--accent);
  background: rgba(245,166,35,0.05);
  box-shadow: 0 0 0 3px rgba(245,166,35,0.12);
}
.form-textarea { resize: vertical; min-height: 80px; }

/* Date input color fix */
input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(0.7) sepia(1) saturate(3) hue-rotate(5deg);
  cursor: pointer;
}

/* ── Priority Group ──────────────────────────────────────── */
.priority-group {
  display: flex;
  gap: 8px;
}
.priority-option { cursor: pointer; }
.priority-option input[type="radio"] { display: none; }
.priority-badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.5px;
  border: 1.5px solid transparent;
  transition: all var(--transition);
  cursor: pointer;
  user-select: none;
}
.priority-badge.low    { color: var(--priority-low);    border-color: rgba(62,207,142,0.3);  background: transparent; }
.priority-badge.medium { color: var(--priority-medium); border-color: rgba(245,166,35,0.3);  background: transparent; }
.priority-badge.high   { color: var(--priority-high);   border-color: rgba(239,68,68,0.3);   background: transparent; }

.priority-option input:checked + .priority-badge.low    { background: var(--green-dim); border-color: var(--priority-low);    box-shadow: 0 0 12px rgba(62,207,142,0.2); }
.priority-option input:checked + .priority-badge.medium { background: var(--accent-dim); border-color: var(--priority-medium); box-shadow: 0 0 12px rgba(245,166,35,0.2); }
.priority-option input:checked + .priority-badge.high   { background: var(--red-dim);    border-color: var(--priority-high);   box-shadow: 0 0 12px rgba(239,68,68,0.2); }

/* ── Add Button ──────────────────────────────────────────── */
.add-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 24px;
  background: linear-gradient(135deg, #e08b10, var(--accent));
  border: none;
  border-radius: var(--radius-sm);
  color: #0a0e1a;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.5px;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
  box-shadow: 0 4px 20px rgba(245,166,35,0.3);
  margin-top: 4px;
}
.add-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(245,166,35,0.45);
}
.add-btn:active { transform: translateY(0); }
.btn-icon { font-size: 18px; transition: transform var(--transition); }
.add-btn:hover .btn-icon { transform: translateX(4px); }

/* ── Error Message ───────────────────────────────────────── */
.error-msg {
  font-size: 12px;
  color: var(--red);
  margin-top: 10px;
  min-height: 18px;
  text-align: center;
  font-weight: 500;
  letter-spacing: 0.3px;
}

/* ── Tasks Panel Header ──────────────────────────────────── */
.tasks-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 12px;
}
.filter-group { display: flex; gap: 6px; }
.filter-btn {
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  font-family: var(--font-body);
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}
.filter-btn:hover { border-color: var(--border-hl); color: var(--text-primary); }
.filter-btn.active {
  background: var(--accent-dim);
  border-color: rgba(245,166,35,0.35);
  color: var(--accent);
}

/* ── Task Cards ──────────────────────────────────────────── */
.tasks-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.task-card {
  background: var(--bg-card-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  position: relative;
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  animation: slideIn 0.3s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes slideIn {
  from { opacity: 0; transform: translateY(14px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}
.task-card:hover {
  transform: translateY(-3px);
  border-color: var(--border-hl);
  box-shadow: var(--shadow);
}
.task-card.completed {
  opacity: 0.6;
  background: rgba(62,207,142,0.03);
  border-color: rgba(62,207,142,0.12);
}
.task-card.completed:hover { opacity: 0.8; }

/* Priority stripe */
.task-card::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 4px;
  border-radius: var(--radius) 0 0 var(--radius);
  background: var(--accent);
}
.task-card[data-priority="low"]::before    { background: var(--priority-low); }
.task-card[data-priority="medium"]::before { background: var(--priority-medium); }
.task-card[data-priority="high"]::before   { background: var(--priority-high); }

/* Checkbox */
.task-check {
  flex-shrink: 0;
  width: 22px; height: 22px;
  border: 2px solid var(--border-hl);
  border-radius: 6px;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: all var(--transition);
  margin-top: 2px;
  background: transparent;
}
.task-check:hover { border-color: var(--green); box-shadow: 0 0 10px rgba(62,207,142,0.2); }
.task-card.completed .task-check {
  background: var(--green);
  border-color: var(--green);
  box-shadow: 0 0 14px rgba(62,207,142,0.35);
}
.task-check-icon {
  color: #0a0e1a;
  font-size: 13px;
  font-weight: 900;
  opacity: 0;
  transform: scale(0);
  transition: all var(--transition);
}
.task-card.completed .task-check-icon {
  opacity: 1;
  transform: scale(1);
}

/* Task body */
.task-body { flex: 1; min-width: 0; }
.task-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 6px;
}
.task-subject {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--accent);
}
.task-priority-tag {
  font-size: 10px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 10px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
}
.task-priority-tag.low    { color: var(--priority-low);    background: var(--green-dim); }
.task-priority-tag.medium { color: var(--priority-medium); background: var(--accent-dim); }
.task-priority-tag.high   { color: var(--priority-high);   background: var(--red-dim); }

.task-desc {
  font-size: 14px;
  color: var(--text-primary);
  line-height: 1.5;
  margin-bottom: 10px;
  word-break: break-word;
}
.task-card.completed .task-desc {
  text-decoration: line-through;
  color: var(--text-secondary);
}

.task-deadline {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 3px 10px;
  background: rgba(255,255,255,0.04);
  border-radius: 12px;
  border: 1px solid var(--border);
}
.task-deadline.overdue {
  color: var(--red);
  background: var(--red-dim);
  border-color: rgba(239,68,68,0.2);
}
.task-deadline.due-soon {
  color: var(--accent);
  background: var(--accent-dim);
  border-color: rgba(245,166,35,0.2);
}

/* Task actions */
.task-actions {
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: flex-end;
  flex-shrink: 0;
}
.task-action-btn {
  width: 30px; height: 30px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 13px;
  transition: all var(--transition);
  color: var(--text-secondary);
}
.task-action-btn.delete:hover {
  background: var(--red-dim);
  border-color: rgba(239,68,68,0.3);
  color: var(--red);
  transform: scale(1.1);
}

/* ── Empty State ─────────────────────────────────────────── */
.empty-state {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 24px;
  text-align: center;
}
.empty-state.visible { display: flex; }
.empty-icon { font-size: 48px; margin-bottom: 16px; opacity: 0.6; }
.empty-title {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  color: var(--text-secondary);
  margin-bottom: 8px;
}
.empty-sub {
  font-size: 13px;
  color: var(--text-muted);
  max-width: 260px;
  line-height: 1.6;
}

/* ── Modal ───────────────────────────────────────────────── */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(6px);
  z-index: 100;
  display: none;
  align-items: center;
  justify-content: center;
  animation: fadeIn 0.2s ease;
}
.modal-overlay.open { display: flex; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal {
  background: var(--bg-card);
  border: 1px solid var(--border-hl);
  border-radius: var(--radius);
  padding: 36px 32px;
  text-align: center;
  max-width: 340px;
  width: 90%;
  animation: modalPop 0.3s cubic-bezier(0.34,1.56,0.64,1);
  box-shadow: var(--shadow-lg);
}
@keyframes modalPop {
  from { opacity: 0; transform: scale(0.88); }
  to   { opacity: 1; transform: scale(1); }
}
.modal-icon { font-size: 32px; margin-bottom: 12px; }
.modal-title {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
}
.modal-body {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}
.modal-actions { display: flex; gap: 10px; }
.modal-btn {
  flex: 1;
  padding: 11px;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  border: 1px solid var(--border);
  transition: all var(--transition);
}
.modal-btn.cancel {
  background: transparent;
  color: var(--text-secondary);
}
.modal-btn.cancel:hover {
  border-color: var(--border-hl);
  color: var(--text-primary);
}
.modal-btn.confirm {
  background: var(--red);
  color: #fff;
  border-color: var(--red);
  box-shadow: 0 4px 14px rgba(239,68,68,0.3);
}
.modal-btn.confirm:hover {
  background: #dc2626;
  box-shadow: 0 6px 20px rgba(239,68,68,0.45);
  transform: translateY(-1px);
}

/* ── Toast ───────────────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--bg-card);
  border: 1px solid var(--border-hl);
  color: var(--text-primary);
  padding: 12px 24px;
  border-radius: 40px;
  font-size: 13px;
  font-weight: 600;
  z-index: 200;
  opacity: 0;
  transition: all 0.35s cubic-bezier(0.34,1.56,0.64,1);
  white-space: nowrap;
  box-shadow: var(--shadow-lg);
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
.toast.success { border-color: rgba(62,207,142,0.4); color: var(--green); }
.toast.error   { border-color: rgba(239,68,68,0.4);  color: var(--red); }
.toast.info    { border-color: rgba(245,166,35,0.4);  color: var(--accent); }

/* ── Scrollbar ───────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.18); }

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 600px) {
  .app-wrapper { padding: 20px 16px 48px; }
  .header { margin-bottom: 20px; }
  .progress-section { padding: 18px 20px; }
  .add-panel, .tasks-panel { padding: 20px 18px; }
  .task-card { padding: 14px 16px; }
  .filter-group { gap: 4px; }
  .filter-btn { padding: 5px 10px; font-size: 11px; }
  .priority-group { flex-wrap: wrap; }
}