/* 全域樣式設定 */
:root {
    --primary-color: #4F46E5;
    --primary-hover: #4338CA;
    --bg-color: #F3F4F6;
    --surface-color: #FFFFFF;
    --text-main: #111827;
    --text-muted: #6B7280;
    --border-color: #E5E7EB;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

body { margin: 0; font-family: 'Inter', sans-serif; background-color: var(--bg-color); color: var(--text-main); }
.navbar { background: var(--surface-color); padding: 1rem 2rem; display: flex; justify-content: space-between; align-items: center; box-shadow: var(--shadow-sm); border-bottom: 1px solid var(--border-color); }
.navbar h1 { margin: 0; font-size: 1.5rem; font-weight: 600; }
.nav-tabs { display: flex; gap: 1rem; }
.auth-controls { display: flex; align-items: center; gap: 0.5rem; }
.tab-btn { padding: 0.5rem 1rem; border: none; background: transparent; color: var(--text-muted); font-weight: 500; cursor: pointer; border-radius: 0.5rem; transition: all 0.3s ease; }
.tab-btn:hover, .tab-btn.active { background: var(--primary-color); color: white; }

.container { padding: 2rem; max-width: 1400px; margin: 0 auto; }
.view-section { display: none; animation: fadeIn 0.3s ease; }
.view-section.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.header-actions { display: flex; justify-content: space-between; align-items: center; margin-bottom: 2rem; flex-wrap: wrap; }
.add-form { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.add-form input, .form-group input, .form-group select { padding: 0.5rem 1rem; border: 1px solid var(--border-color); border-radius: 0.5rem; outline: none; font-family: inherit; width: 100%; box-sizing: border-box; }
.add-form input:focus, .form-group input:focus, .form-group select:focus { border-color: var(--primary-color); }
.small-input { width: 120px; }

.btn-primary { background: var(--primary-color); color: white; border: none; padding: 0.5rem 1.5rem; border-radius: 0.5rem; cursor: pointer; font-weight: 500; transition: background 0.3s; white-space: nowrap; }
.btn-primary:hover { background: var(--primary-hover); }

.board { display: flex; gap: 1.5rem; overflow-x: auto; padding-bottom: 1rem; }
.column { flex: 1; min-width: 300px; background: #F9FAFB; border-radius: 0.75rem; padding: 1rem; border: 1px solid var(--border-color); }
.column h3 { margin: 0 0 1rem 0; font-size: 1rem; color: var(--text-muted); }

.card-list { display: flex; flex-direction: column; gap: 0.75rem; min-height: 100px; }
.card { background: var(--surface-color); padding: 1rem; border-radius: 0.5rem; box-shadow: var(--shadow-sm); border: 1px solid var(--border-color); display: flex; flex-direction: column; gap: 0.5rem; transition: transform 0.2s, box-shadow 0.2s; }
.card:hover { box-shadow: var(--shadow-md); }
.card-header { display: flex; justify-content: space-between; align-items: flex-start; }
.card-title { font-weight: 600; font-size: 1.05rem; color: var(--text-main); flex: 1; display: flex; align-items: center; gap: 0.5rem; word-break: break-all;}
.btn-edit { background: transparent; border: none; cursor: pointer; font-size: 1rem; color: var(--text-muted); }
.btn-edit:hover { color: var(--primary-color); }
.card-details { display: flex; flex-direction: column; gap: 0.2rem; }
.card-date { font-size: 0.8rem; color: #DC2626; font-weight: 500; }
.card-assignee { font-size: 0.85rem; color: var(--primary-color); font-weight: 500; background-color: #EEF2FF; padding: 0.15rem 0.5rem; border-radius: 0.25rem; align-self: flex-start; }
.card-notes { font-size: 0.85rem; color: var(--text-muted); }
.stage-selector { padding: 0.2rem 0.5rem; border-radius: 0.25rem; border: 1px solid var(--border-color); font-size: 0.8rem; color: var(--text-muted); background-color: var(--surface-color); cursor: pointer; }

.tasks-section { border-top: 1px dashed var(--border-color); padding-top: 0.5rem; margin-top: 0.25rem; display: flex; flex-direction: column; gap: 0.4rem; }
.task-item { font-size: 0.85rem; display: flex; align-items: center; gap: 0.4rem; }
.task-checkbox { cursor: pointer; }
.task-completed .task-name { text-decoration: line-through; color: var(--text-muted); }
.task-name { flex: 1; }
.task-meta { font-size: 0.75rem; color: var(--text-muted); border-left: 1px solid var(--border-color); padding-left: 0.3rem;}
.btn-add-task { background: #F3F4F6; border: none; border-radius: 0.25rem; font-size: 0.8rem; padding: 0.3rem; color: var(--text-muted); cursor: pointer; margin-top: 0.25rem; }
.btn-add-task:hover { background: #E5E7EB; color: var(--text-main); }

.modal { display: none; position: fixed; z-index: 100; left: 0; top: 0; width: 100%; height: 100%; background-color: rgba(0,0,0,0.5); animation: fadeIn 0.2s ease; }
.modal.active { display: flex; align-items: center; justify-content: center; }
.modal-content { background-color: #fefefe; padding: 2rem; border: none; width: 90%; max-width: 400px; border-radius: 1rem; box-shadow: var(--shadow-md); position: relative; }
.close-btn { position: absolute; right: 1.5rem; top: 1.5rem; color: #aaa; font-size: 28px; font-weight: bold; cursor: pointer; line-height: 1;}
.close-btn:hover { color: black; }
.form-group { display: flex; flex-direction: column; gap: 0.5rem; margin-bottom: 1rem; }
.form-group label { font-size: 0.85rem; font-weight: 500; color: var(--text-muted); }

/* Admin View Styles */
.admin-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1.5rem; }
.admin-card { background: var(--surface-color); padding: 1.5rem; border-radius: 0.5rem; box-shadow: var(--shadow-sm); border: 1px solid var(--border-color); }
.admin-card h3 { margin-top: 0; color: var(--primary-color); font-size: 1.2rem; margin-bottom: 1rem; }
.data-list { max-height: 150px; overflow-y: auto; font-size: 0.85rem; margin-top: 0.5rem; border-top: 1px solid var(--border-color); padding-top: 0.5rem; color: var(--text-main); }
.data-item { padding: 0.35rem 0; border-bottom: 1px solid #E5E7EB; display:flex; justify-content:space-between; align-items:center; }
.data-item:last-child { border-bottom: none; }