/* css/assign.css – Modern, polished assignment maker */

:root {
  --assign-accent: #009688;
  --assign-accent-soft: rgba(0, 150, 136, 0.08);
  --assign-surface: #ffffff;
  --assign-bg: #f5f7f9;
  --assign-border: #e8ecf1;
  --assign-text: #1f2933;
  --assign-text-secondary: #6b7280;
  --assign-shadow: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.03);
  --assign-shadow-lg: 0 20px 40px -12px rgba(0,0,0,0.08), 0 8px 20px -8px rgba(0,0,0,0.04);
  --assign-radius: 1.25rem;
  --assign-radius-sm: 0.85rem;
  --assign-radius-xs: 0.6rem;
  --assign-transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
  --assign-accent: #14b8a6;
  --assign-accent-soft: rgba(20, 184, 166, 0.12);
  --assign-surface: #1a252c;
  --assign-bg: #0f181e;
  --assign-border: #263238;
  --assign-text: #e2e8f0;
  --assign-text-secondary: #8899a6;
  --assign-shadow: 0 1px 3px rgba(0,0,0,0.2);
  --assign-shadow-lg: 0 20px 40px -12px rgba(0,0,0,0.3);
}

/* ===== Layout ===== */
.assign-main {
  padding: 2rem 1.5rem 3rem;
  background: var(--assign-bg);
  min-height: calc(100vh - 60px);
  display: flex;
  justify-content: center;
}

.assign-container {
  width: 100%;
  max-width: 820px;
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

/* ===== Glass Card ===== */
.glass-card {
  background: var(--assign-surface);
  border: 1px solid var(--assign-border);
  border-radius: var(--assign-radius);
  box-shadow: var(--assign-shadow);
  transition: box-shadow var(--assign-transition), border-color var(--assign-transition);
}

.glass-card:hover {
  box-shadow: var(--assign-shadow-lg);
  border-color: rgba(0, 150, 136, 0.2);
}

/* ===== Input Card ===== */
.assign-input-card {
  padding: 2rem 2rem 1.75rem;
}

.card-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.75rem;
}

.card-header-icon {
  width: 48px;
  height: 48px;
  border-radius: 0.9rem;
  background: linear-gradient(135deg, var(--assign-accent), #26a69a);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.card-header h2 {
  margin: 0;
  font-size: 1.35rem;
  font-weight: 650;
  color: var(--assign-text);
  letter-spacing: -0.01em;
}

.card-subtitle {
  margin: 0.15rem 0 0;
  font-size: 0.88rem;
  color: var(--assign-text-secondary);
}

/* ===== Form ===== */
.assign-form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-group label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--assign-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1.5px solid var(--assign-border);
  border-radius: var(--assign-radius-sm);
  background: var(--assign-bg);
  color: var(--assign-text);
  font-family: inherit;
  font-size: 0.93rem;
  outline: none;
  transition: all var(--assign-transition);
  resize: vertical;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--assign-accent);
  box-shadow: 0 0 0 4px var(--assign-accent-soft);
  background: var(--assign-surface);
}

.form-group select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  padding-right: 2.5rem;
}

/* ===== Textarea with attachment button ===== */
.topic-group {
  position: relative;
}

.textarea-wrapper {
  position: relative;
}

.textarea-wrapper textarea {
  padding-right: 3.5rem;
  min-height: 100px;
}

.attach-btn {
  position: absolute;
  bottom: 0.75rem;
  right: 0.75rem;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--assign-accent);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  transition: all var(--assign-transition);
  box-shadow: 0 4px 12px rgba(0, 150, 136, 0.3);
  z-index: 2;
}

.attach-btn:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 16px rgba(0, 150, 136, 0.45);
}

.attach-btn:active {
  transform: scale(0.95);
}

/* File chip */
.file-chip {
  margin-top: 0.5rem;
  padding: 0.5rem 0.85rem;
  background: var(--assign-accent-soft);
  border: 1px solid rgba(0, 150, 136, 0.2);
  border-radius: 2rem;
  font-size: 0.82rem;
  color: var(--assign-accent);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 500;
  animation: fadeIn 0.3s ease;
}

.file-chip .remove-file {
  background: none;
  border: none;
  color: var(--assign-accent);
  cursor: pointer;
  font-size: 1rem;
  padding: 0;
  line-height: 1;
  opacity: 0.7;
  transition: opacity 0.2s;
}

.file-chip .remove-file:hover {
  opacity: 1;
}

/* ===== Form Rows ===== */
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-row-triple {
  grid-template-columns: 1fr 1fr 1fr;
}

/* Volume group (inline input + select) */
.volume-group {
  display: flex;
  gap: 0.5rem;
}

.volume-group input {
  flex: 1;
  min-width: 0;
}

.volume-group select {
  width: 110px;
  flex-shrink: 0;
}

/* ===== Generate Button ===== */
.generate-btn {
  width: 100%;
  padding: 0.95rem;
  background: linear-gradient(135deg, var(--assign-accent), #26a69a);
  color: white;
  border: none;
  border-radius: 3rem;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  transition: all var(--assign-transition);
  font-family: inherit;
  letter-spacing: 0.01em;
  box-shadow: 0 4px 16px rgba(0, 150, 136, 0.25);
  margin-top: 0.5rem;
}

.generate-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 150, 136, 0.35);
}

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

.generate-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  box-shadow: none;
}

/* ===== Results ===== */
.results-container {
  animation: fadeSlideUp 0.4s ease;
}

.results-card {
  padding: 0;
  overflow: hidden;
}

.results-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.9rem 1.4rem;
  background: var(--assign-bg);
  border-bottom: 1px solid var(--assign-border);
  flex-wrap: wrap;
  gap: 0.75rem;
}

.toolbar-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.toolbar-badge {
  background: var(--assign-accent-soft);
  color: var(--assign-accent);
  padding: 0.25rem 0.75rem;
  border-radius: 1rem;
  font-size: 0.78rem;
  font-weight: 600;
}

.toolbar-date {
  font-size: 0.78rem;
  color: var(--assign-text-secondary);
}

.toolbar-right {
  display: flex;
  gap: 0.3rem;
  align-items: center;
}

.tool-btn {
  background: transparent;
  border: 1px solid var(--assign-border);
  padding: 0.4rem 0.75rem;
  border-radius: var(--assign-radius-xs);
  cursor: pointer;
  color: var(--assign-text-secondary);
  font-size: 0.82rem;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: all var(--assign-transition);
  font-family: inherit;
  font-weight: 500;
}

.tool-btn:hover {
  background: var(--assign-accent-soft);
  color: var(--assign-accent);
  border-color: var(--assign-accent);
}

.results-body {
  padding: 1.5rem 1.75rem;
}

.results-editor {
  min-height: 400px;
  outline: none;
  line-height: 1.75;
  color: var(--assign-text);
  font-size: 0.95rem;
}

.results-editor:focus {
  outline: none;
}

.results-editor h1,
.results-editor h2,
.results-editor h3 {
  color: var(--assign-accent);
  margin-top: 1.5em;
  margin-bottom: 0.4em;
}

.results-editor p {
  margin: 0.6em 0;
}

.results-editor ul,
.results-editor ol {
  padding-left: 1.5rem;
  margin: 0.5em 0;
}

/* ===== Loading ===== */
.results-loading {
  text-align: center;
  background: var(--assign-surface);
  border: 1px solid var(--assign-border);
  border-radius: var(--assign-radius);
  box-shadow: var(--assign-shadow);
  animation: fadeIn 0.3s ease;
}

.loading-content {
  padding: 3.5rem 2rem;
}

.spinner {
  width: 44px;
  height: 44px;
  border: 3px solid var(--assign-border);
  border-top-color: var(--assign-accent);
  border-radius: 50%;
  margin: 0 auto 1.25rem;
  animation: spin 0.7s linear infinite;
}

.loading-content p {
  color: var(--assign-text);
  font-weight: 500;
  margin: 0 0 0.3rem;
  font-size: 1rem;
}

.loading-content span {
  font-size: 0.82rem;
  color: var(--assign-text-secondary);
}

/* ===== Upload Modal ===== */
.upload-modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 10000;
  display: none;
  align-items: center;
  justify-content: center;
}

.upload-modal.active {
  display: flex;
  animation: fadeIn 0.25s ease;
}

.upload-modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
}

.upload-modal-card {
  position: relative;
  background: var(--assign-surface);
  border-radius: 1.5rem;
  max-width: 400px;
  width: 90%;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  overflow: hidden;
  animation: slideUp 0.3s ease;
}

.upload-modal-header {
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--assign-border);
}

.upload-modal-header h3 {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--assign-text);
}

.upload-modal-close {
  background: var(--assign-bg);
  border: none;
  color: var(--assign-text-secondary);
  font-size: 1.4rem;
  cursor: pointer;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--assign-transition);
}

.upload-modal-close:hover {
  background: #fee2e2;
  color: #dc2626;
}

.upload-modal-body {
  padding: 1.25rem 1.5rem 1.5rem;
}

.upload-options-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.6rem;
}

.upload-option {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.1rem;
  background: var(--assign-bg);
  border: 1.5px solid var(--assign-border);
  border-radius: var(--assign-radius-sm);
  cursor: pointer;
  transition: all var(--assign-transition);
  text-align: left;
  width: 100%;
  font-family: inherit;
}

.upload-option:hover {
  border-color: var(--assign-accent);
  background: var(--assign-accent-soft);
  transform: translateX(4px);
}

.upload-option-icon {
  width: 44px;
  height: 44px;
  border-radius: 0.7rem;
  background: var(--assign-accent-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--assign-accent);
  font-size: 1.1rem;
  flex-shrink: 0;
}

.upload-option-label {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--assign-text);
  display: block;
}

.upload-option-desc {
  font-size: 0.78rem;
  color: var(--assign-text-secondary);
  display: block;
  margin-top: 0.1rem;
}

/* ===== History Drawer ===== */
.history-drawer {
  position: fixed;
  top: 0;
  left: -420px;
  width: 420px;
  height: 100vh;
  background: var(--assign-surface);
  border-right: 1px solid var(--assign-border);
  z-index: 1000;
  transition: left var(--assign-transition);
  display: flex;
  flex-direction: column;
  box-shadow: var(--assign-shadow-lg);
}

.history-drawer.active {
  left: 0;
}

.drawer-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--assign-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.drawer-header h3 {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.1rem;
  color: var(--assign-text);
}

.drawer-close-btn {
  background: var(--assign-bg);
  border: none;
  font-size: 1.3rem;
  cursor: pointer;
  color: var(--assign-text-secondary);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--assign-transition);
}

.drawer-close-btn:hover {
  background: var(--assign-accent-soft);
  color: var(--assign-accent);
}

.history-search {
  padding: 0.9rem 1.2rem;
  border-bottom: 1px solid var(--assign-border);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--assign-bg);
}

.history-search input {
  flex: 1;
  padding: 0.6rem 0.9rem;
  border: 1px solid var(--assign-border);
  border-radius: 2rem;
  background: var(--assign-surface);
  color: var(--assign-text);
  font-size: 0.88rem;
  font-family: inherit;
  outline: none;
}

.history-search input:focus {
  border-color: var(--assign-accent);
}

.history-content {
  flex: 1;
  overflow-y: auto;
  padding: 1rem 1.2rem;
}

.history-item {
  background: var(--assign-bg);
  border-radius: var(--assign-radius-sm);
  padding: 1rem 1.1rem;
  margin-bottom: 0.65rem;
  border: 1px solid var(--assign-border);
  cursor: pointer;
  transition: all var(--assign-transition);
}

.history-item:hover {
  border-color: var(--assign-accent);
  transform: translateX(-3px);
}

.history-title {
  font-weight: 600;
  display: block;
  margin-bottom: 0.3rem;
  color: var(--assign-text);
  font-size: 0.93rem;
}

.history-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.75rem;
  color: var(--assign-text-secondary);
}

.history-item .delete-btn {
  float: right;
  background: none;
  border: none;
  color: var(--assign-text-secondary);
  cursor: pointer;
  padding: 4px 6px;
  border-radius: 0.4rem;
  transition: all 0.2s;
  font-size: 0.9rem;
}

.history-item .delete-btn:hover {
  background: #fee2e2;
  color: #dc2626;
}

.empty-state {
  text-align: center;
  padding: 2.5rem 1rem;
  color: var(--assign-text-secondary);
}

.empty-state i {
  font-size: 2.5rem;
  display: block;
  margin-bottom: 0.5rem;
  opacity: 0.4;
}

/* ===== Toast ===== */
#toast-container {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.toast {
  background: var(--assign-surface);
  border-left: 4px solid var(--assign-accent);
  padding: 0.8rem 1.2rem;
  border-radius: 0.8rem;
  box-shadow: var(--assign-shadow-lg);
  color: var(--assign-text);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  animation: slideUp 0.3s ease;
  font-size: 0.88rem;
  font-weight: 500;
}

.toast.success { border-left-color: #10b981; }
.toast.error { border-left-color: #dc2626; }

/* ===== Animations ===== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes fadeSlideUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .assign-main {
    padding: 1.25rem 0.8rem 2rem;
  }

  .assign-input-card {
    padding: 1.5rem 1.2rem 1.25rem;
  }

  .card-header-icon {
    width: 40px;
    height: 40px;
    font-size: 1rem;
  }

  .card-header h2 {
    font-size: 1.2rem;
  }

  .form-row {
    grid-template-columns: 1fr;
    gap: 0.9rem;
  }

  .form-row-triple {
    grid-template-columns: 1fr;
  }

  .results-body {
    padding: 1rem 1.2rem;
  }

  .history-drawer {
    width: 320px;
    left: -320px;
  }
}

@media (max-width: 480px) {
  .assign-input-card {
    padding: 1.25rem 1rem 1rem;
    border-radius: 1.1rem;
  }

  .results-card {
    border-radius: 1.1rem;
  }

  .results-toolbar {
    padding: 0.7rem 1rem;
  }

  .tool-btn {
    padding: 0.35rem 0.6rem;
    font-size: 0.78rem;
  }

  .attach-btn {
    width: 34px;
    height: 34px;
    bottom: 0.6rem;
    right: 0.6rem;
  }
}


/* ===== Outline Toggle ===== */
.outline-toggle-group {
  gap: 0.6rem;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  cursor: pointer;
  font-size: 0.88rem;
  color: var(--assign-text);
  font-weight: 500;
  user-select: none;
}

.checkbox-label input[type="checkbox"] {
  display: none;
}

.checkbox-custom {
  width: 20px;
  height: 20px;
  border: 2px solid var(--assign-border);
  border-radius: 0.35rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all var(--assign-transition);
  flex-shrink: 0;
}

.checkbox-custom::after {
  content: '';
  width: 10px;
  height: 10px;
  background: var(--assign-accent);
  border-radius: 0.15rem;
  transform: scale(0);
  transition: transform 0.2s ease;
}

.checkbox-label input:checked + .checkbox-custom {
  border-color: var(--assign-accent);
  background: var(--assign-accent-soft);
}

.checkbox-label input:checked + .checkbox-custom::after {
  transform: scale(1);
}

.outline-hint {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.75rem;
  background: var(--assign-accent-soft);
  border-radius: 0.5rem;
  font-size: 0.8rem;
  color: var(--assign-accent);
  animation: fadeIn 0.3s ease;
}

.outline-hint i {
  font-size: 0.85rem;
}

/* ===== Preview Modal ===== */
.preview-modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeIn 0.3s ease;
}

.preview-modal.active {
  display: flex;
}

.preview-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.preview-card {
  position: relative;
  background: var(--assign-surface);
  border-radius: 1.5rem;
  max-width: 500px;
  width: 90%;
  margin: 1rem;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  animation: slideUp 0.3s ease;
  overflow: hidden;
}

.preview-card-header {
  background: linear-gradient(135deg, var(--assign-accent), #26a69a);
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: white;
}

.preview-icon {
  font-size: 1.8rem;
  line-height: 1;
}

.preview-card-header h3 {
  margin: 0;
  flex: 1;
  font-size: 1.2rem;
  font-weight: 600;
}

.preview-close {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

.preview-close:hover {
  background: rgba(255, 255, 255, 0.35);
  transform: scale(1.1);
}

.preview-card-body {
  padding: 1.5rem;
}

.preview-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.preview-badge {
  background: var(--assign-accent-soft);
  color: var(--assign-accent);
  padding: 0.35rem 0.85rem;
  border-radius: 2rem;
  font-size: 0.8rem;
  font-weight: 600;
}

.preview-date {
  font-size: 0.78rem;
  color: var(--assign-text-secondary);
}

.preview-description {
  margin-bottom: 1.25rem;
  line-height: 1.5;
  color: var(--assign-text);
}

.preview-actions {
  display: flex;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.preview-btn {
  flex: 1;
  padding: 0.75rem 1.25rem;
  border-radius: 2.5rem;
  font-size: 0.93rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
  text-align: center;
  white-space: nowrap;
  font-family: inherit;
}

.preview-btn.primary {
  background: var(--assign-accent);
  color: white;
}

.preview-btn.primary:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 150, 136, 0.3);
}

.preview-btn.secondary {
  background: var(--assign-bg);
  border: 1px solid var(--assign-border);
  color: var(--assign-text);
}

.preview-btn.secondary:hover {
  background: var(--assign-border);
  transform: translateY(-2px);
}

.preview-note {
  text-align: center;
  font-size: 0.8rem;
  color: var(--assign-text-secondary);
}

/* ===== Dark mode for modal ===== */
[data-theme="dark"] .preview-card {
  background: #1a252c;
}

[data-theme="dark"] .preview-btn.secondary {
  background: #263238;
  color: #e2e8f0;
  border-color: #37474f;
}

[data-theme="dark"] .preview-btn.secondary:hover {
  background: #37474f;
}

[data-theme="dark"] .checkbox-custom {
  border-color: #37474f;
}