/* =========================
   yles503 後台管理：全站樣式
   - 與 student.css 配色一致（天藍主題）
   - 不改動你既有 HTML 結構與 class 命名
   ========================= */

:root{
  --bg:#f6f7fb; --card:#fff; --text:#1f2937; --muted:#6b7280; --ring:#e5e7eb;
  /* 天藍主題 */
  --brand:#3B82F6; --brand-2:#2563EB; --accent:#0EA5E9;
  --card-dark:#1F2A44; --bg-dark:#111827; --text-dark:#e5e7eb; --muted-dark:#9ca3af; --ring-dark:#374151;
  --radius:16px; --shadow:0 8px 24px rgba(0,0,0,.08); --shadow-2:0 12px 32px rgba(0,0,0,.12);
  --t-fast:.18s cubic-bezier(.2,.8,.2,1); --t-base:.28s cubic-bezier(.2,.8,.2,1);
}

/* 基礎 */
*{ box-sizing:border-box; }
body{ background:var(--bg); color:var(--text); margin:0; }
.dark body{ background:var(--bg-dark); color:var(--text-dark); }

.container{ max-width:1100px; margin:auto; padding:20px; }
@media (max-width:768px){ .container{ padding:12px; } }

a{ color:var(--brand); text-decoration:none; }
a:hover{ color:var(--brand-2); text-decoration:none; }
.muted{ color:var(--muted); } .dark .muted{ color:var(--muted-dark); }
.hidden{ display:none !important; }

/* 卡片 */
.card{
  background:var(--card);
  border:1px solid var(--ring);
  border-radius:var(--radius);
  padding:16px;
  box-shadow:var(--shadow);
  transition: box-shadow var(--t-base), transform var(--t-fast), border-color var(--t-fast), background var(--t-fast);
}
.card:hover{ box-shadow:var(--shadow-2); transform:translateY(-2px); }
.dark .card{ background:var(--card-dark); border-color:var(--ring-dark); }
.card-title{ font-weight:800; letter-spacing:.02em; margin-bottom:10px; }

/* 工具列 */
.toolbar{
  display:flex; gap:8px; align-items:center; flex-wrap:wrap;
  margin:12px 0 16px;
}
.toolbar .spacer{ flex:1; }

/* 控制元件 */
.btn{
  appearance:none; border:1px solid var(--ring); background:#fff; color:var(--text);
  padding:10px 14px; border-radius:12px; cursor:pointer; min-height:40px;
  transition: transform .1s ease, box-shadow var(--t-fast), background var(--t-fast), border-color var(--t-fast), color var(--t-fast);
  display:inline-flex; align-items:center; gap:8px;
}
.btn:hover{ box-shadow:0 10px 24px rgba(0,0,0,.08); transform:translateY(-1px); }
.btn:active{ transform:scale(.98); }
.btn.ok{ background:linear-gradient(180deg,#3B82F6,#2563EB); color:#fff; border-color:transparent; }
.btn.ok:hover{ box-shadow:0 12px 28px rgba(59,130,246,.35); }
.btn.danger{ background:linear-gradient(180deg,#ef4444,#dc2626); color:#fff; border-color:transparent; }
.btn.danger:hover{ box-shadow:0 12px 28px rgba(239,68,68,.35); }
.btn.ghost{ background:transparent; }
.dark .btn{ background:var(--card-dark); border-color:var(--ring-dark); color:var(--text-dark); }
.dark .btn.ok,.dark .btn.danger{ color:#fff; }

.input, select, textarea{
  width:100%; padding:10px 12px; border-radius:12px;
  border:1px solid var(--ring); background:#fff; color:inherit; outline:none;
  transition:border-color var(--t-fast), box-shadow var(--t-fast), background var(--t-fast);
}
.input:focus, select:focus, textarea:focus{
  border-color:var(--brand); box-shadow:0 0 0 4px rgba(59,130,246,.15);
}
.dark .input, .dark select, .dark textarea{ background:var(--card-dark); border-color:var(--ring-dark); color:var(--text-dark); }

.form{ display:grid; gap:12px; }
.form .row{ display:grid; grid-template-columns:1fr 1fr; gap:12px; }
@media (max-width:768px){ .form .row{ grid-template-columns:1fr; } }
label{ display:grid; gap:6px; font-size:14px; color:var(--muted); }
.dark label{ color:var(--muted-dark); }

.actions-row{ display:flex; gap:8px; flex-wrap:wrap; margin-top:8px; }
.notice{ margin-top:8px; color:var(--muted); font-size:13px; }

/* 徽章 */
.badge{
  display:inline-flex; align-items:center; gap:6px;
  padding:4px 10px; border-radius:999px; font-size:12px;
  border:1px solid var(--ring); background:linear-gradient(180deg,#fff,rgba(255,255,255,.95));
}
.badge.ok{ color:#0a7; border-color:rgba(16,185,129,.35); }
.badge.danger{ color:#e11; border-color:rgba(239,68,68,.35); }
.dark .badge{ background:var(--card-dark); border-color:var(--ring-dark); }

/* 表格（含排序、斑馬、sticky head） */
.table-wrap{ overflow:auto; border-radius:14px; border:1px solid var(--ring); background:var(--card); }
.dark .table-wrap{ background:var(--card-dark); border-color:var(--ring-dark); }

table{ width:100%; border-collapse:separate; border-spacing:0; min-width:720px; }
th,td{ padding:12px 12px; border-bottom:1px solid var(--ring); text-align:left; vertical-align:middle; }
.dark th,.dark td{ border-bottom-color:var(--ring-dark); }
thead th{
  position:sticky; top:0; background:linear-gradient(180deg,rgba(0,0,0,.02),transparent);
  font-weight:800; letter-spacing:.02em; z-index:1;
}
tbody tr:nth-child(odd){ background:rgba(0,0,0,.02); }
tbody tr:hover{ background:rgba(59,130,246,.06); }
.dark tbody tr:nth-child(odd){ background:rgba(255,255,255,.03); }
.dark tbody tr:hover{ background:rgba(59,130,246,.12); }

th.sortable{ cursor:pointer; user-select:none; }
th.sortable .caret{ font-size:11px; opacity:.6; margin-left:6px; }

/* 搜尋列 / 篩選 */
.searchbar{
  display:flex; gap:8px; flex-wrap:wrap; align-items:center; margin:6px 0 10px;
}
.searchbar .input{ min-width:260px; }

/* Modal */
.modal{ position:fixed; inset:0; display:grid; place-items:center; background:rgba(0,0,0,.55); z-index:60; }
.modal.hidden{ display:none !important; }
.modal-content{ width:min(680px, calc(100vw - 32px)); animation:zoomIn .22s var(--t-fast); }

/* Loading Overlay / Skeleton */
.loading-overlay{
  position:fixed; inset:0; display:grid; place-items:center; z-index:70;
  background:rgba(255,255,255,.55); backdrop-filter:saturate(180%) blur(4px);
}
.dark .loading-overlay{ background:rgba(17,24,39,.55); }

.skeleton{ background:linear-gradient(90deg,#eee,#f5f5f5,#eee); background-size:200% 100%; animation:skeleton 1.2s ease infinite; border-radius:10px; }
.dark .skeleton{ background:linear-gradient(90deg,#303847,#394257,#303847); }

@keyframes skeleton{
  0%{ background-position:200% 0; }
  100%{ background-position:-200% 0; }
}

/* Toast */
.toast{ position:fixed; right:16px; bottom:16px; display:grid; gap:10px; z-index:80; }
.toast .item{
  background:#111827; color:#fff; padding:12px 14px; border-radius:12px; box-shadow:var(--shadow-2); animation:fadeIn .2s ease;
}
.toast .item.ok{ background:#065f46; }
.toast .item.err{ background:#7f1d1d; }

/* 分頁器（可選） */
.pager{ display:flex; gap:6px; align-items:center; justify-content:flex-end; margin-top:10px; }
.pager .btn{ padding:8px 10px; min-height:36px; }

/* 動畫 */
@keyframes fadeIn{ from{opacity:0; transform:translateY(4px)} to{opacity:1; transform:none} }
@keyframes zoomIn{ from{opacity:0; transform:scale(.96)} to{opacity:1; transform:scale(1)} }

/* === 覆蓋：把上方選單灰色背景拿掉、hover/active 走天藍 === */
.tabs{
  background: transparent !important;
  padding: 0 !important;
}
.tabs a{
  border-radius: 999px;
  padding: 10px 14px;
  transition: background .18s ease, color .18s ease, box-shadow .18s ease;
}
.tabs a:hover{
  background: rgba(59,130,246,.12) !important; /* 天藍 hover */
  color: var(--brand) !important;
  text-decoration: none;
}
.tabs a.active{
  background: rgba(59,130,246,.18) !important; /* 天藍 active */
  color: var(--brand) !important;
  box-shadow: 0 2px 6px rgba(59,130,246,.18);
}