/* =============================================================
   Python编程学习平台 · 赛博霓虹风格样式
   深色背景 + 青色霓虹 + 玻璃质感 + 大圆角
   ============================================================= */

:root {
  --bg-deep: #060a14;
  --bg-panel: rgba(13, 22, 43, 0.72);
  --bg-panel-solid: #0d162b;
  --neon-cyan: #00e5ff;
  --neon-magenta: #ff2fd6;
  --neon-purple: #8b5cf6;
  --neon-green: #4ade80;
  --neon-amber: #fbbf24;
  --text-main: #e6f1ff;
  --text-dim: #93a4c3;
  --border-glow: rgba(0, 229, 255, 0.35);
  --radius-lg: 18px;
  --radius-md: 12px;
  --shadow-neon: 0 0 18px rgba(0, 229, 255, 0.22), 0 8px 30px rgba(0, 0, 0, 0.45);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  background:
    radial-gradient(1200px 600px at 85% -10%, rgba(139, 92, 246, 0.16), transparent 60%),
    radial-gradient(900px 500px at -10% 110%, rgba(0, 229, 255, 0.12), transparent 60%),
    var(--bg-deep);
  color: var(--text-main);
  min-height: 100vh;
  line-height: 1.7;
}

a { color: var(--neon-cyan); text-decoration: none; }
a:hover { text-shadow: 0 0 8px rgba(0, 229, 255, 0.6); }

/* ---------- 导航栏 ---------- */
.navbar {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; gap: 24px;
  padding: 14px 28px;
  background: rgba(6, 10, 20, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-glow);
  box-shadow: 0 2px 24px rgba(0, 229, 255, 0.08);
}

.brand { font-size: 20px; font-weight: 800; letter-spacing: 1px; }
.brand .logo {
  background: linear-gradient(90deg, var(--neon-cyan), var(--neon-purple));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}

.nav-links { display: flex; gap: 6px; flex: 1; flex-wrap: wrap; }
.nav-links a {
  color: var(--text-main); padding: 8px 14px; border-radius: 999px;
  font-size: 14px; transition: all .2s;
}
.nav-links a:hover, .nav-links a.active {
  color: var(--bg-deep);
  background: linear-gradient(90deg, var(--neon-cyan), var(--neon-purple));
  box-shadow: 0 0 14px rgba(0, 229, 255, 0.45);
  text-shadow: none;
}

.nav-actions { display: flex; gap: 10px; align-items: center; }

/* 汉堡菜单（移动端） */
.hamburger { display: none; background: none; border: 1px solid var(--border-glow); color: var(--neon-cyan); font-size: 20px; border-radius: 10px; padding: 4px 12px; cursor: pointer; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block; padding: 9px 20px; border-radius: 999px;
  border: 1px solid var(--border-glow); background: rgba(0, 229, 255, 0.08);
  color: var(--neon-cyan); font-size: 14px; cursor: pointer;
  transition: all .2s; text-decoration: none; text-align: center;
}
.btn:hover {
  background: linear-gradient(90deg, var(--neon-cyan), var(--neon-purple));
  color: var(--bg-deep); box-shadow: 0 0 16px rgba(0, 229, 255, 0.5);
  text-shadow: none;
}
.btn-solid {
  background: linear-gradient(90deg, var(--neon-cyan), var(--neon-purple));
  color: var(--bg-deep); font-weight: 700; border: none;
}
.btn-ghost { background: transparent; }
.btn-danger { border-color: rgba(255, 80, 80, .5); color: #ff6b6b; background: rgba(255, 80, 80, .08); }
.btn-danger:hover { background: #ff6b6b; color: #fff; }
.btn-sm { padding: 5px 12px; font-size: 13px; }

/* ---------- 卡片 ---------- */
.glass-card {
  background: var(--bg-panel);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 24px;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-neon);
  transition: transform .2s, box-shadow .2s;
}
.glass-card:hover { transform: translateY(-3px); box-shadow: 0 0 26px rgba(0, 229, 255, 0.3), 0 10px 34px rgba(0, 0, 0, 0.5); }

.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 20px; }

/* ---------- 页面容器 ---------- */
.container { max-width: 1160px; margin: 0 auto; padding: 36px 20px 60px; }
.page-title { font-size: 28px; font-weight: 800; margin-bottom: 6px; }
.page-sub { color: var(--text-dim); margin-bottom: 26px; }
.section-title { font-size: 20px; font-weight: 700; margin: 30px 0 16px; color: var(--neon-cyan); }

/* ---------- 徽章 / 标签 ---------- */
.badge {
  display: inline-block; padding: 3px 12px; border-radius: 999px; font-size: 12px;
  border: 1px solid var(--border-glow); color: var(--neon-cyan); background: rgba(0, 229, 255, 0.08);
}
.badge-warn { color: var(--neon-amber); border-color: rgba(251, 191, 36, .4); background: rgba(251, 191, 36, .08); }
.badge-green { color: var(--neon-green); border-color: rgba(74, 222, 128, .4); background: rgba(74, 222, 128, .08); }

/* ---------- 表单 ---------- */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; margin-bottom: 6px; color: var(--text-dim); font-size: 14px; }
input[type="text"], input[type="password"], input[type="email"], input[type="number"], input[type="url"],
select, textarea {
  width: 100%; padding: 10px 14px; border-radius: var(--radius-md);
  background: rgba(6, 10, 20, 0.7); color: var(--text-main);
  border: 1px solid var(--border-glow); font-size: 14px; outline: none;
}
input:focus, select:focus, textarea:focus { border-color: var(--neon-cyan); box-shadow: 0 0 10px rgba(0, 229, 255, 0.35); }
textarea { min-height: 120px; font-family: "Consolas", monospace; }

/* ---------- 表格 ---------- */
.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th, .table td { padding: 10px 12px; border-bottom: 1px solid rgba(0, 229, 255, 0.12); text-align: left; }
.table th { color: var(--neon-cyan); font-weight: 600; background: rgba(0, 229, 255, 0.05); }
.table tr:hover td { background: rgba(0, 229, 255, 0.04); }

/* ---------- 代码块 ---------- */
.code-block {
  background: #0a0f1e; border: 1px solid var(--border-glow); border-radius: var(--radius-md);
  padding: 16px; overflow-x: auto; font-family: "Consolas", "Courier New", monospace;
  font-size: 13px; line-height: 1.6; color: #d8f6ff; margin: 10px 0;
}
.code-block .code-line { display: block; white-space: pre; }
.kw { color: var(--neon-magenta); }
.fn { color: var(--neon-amber); }
.str { color: var(--neon-green); }

.copy-btn { float: right; }

/* ---------- 进度条 ---------- */
.progress { height: 8px; background: rgba(255,255,255,.06); border-radius: 999px; overflow: hidden; }
.progress > i { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--neon-cyan), var(--neon-purple)); }

/* ---------- 工具卡片 ---------- */
.tool-card { cursor: pointer; text-align: center; }
.tool-card .tool-icon { font-size: 46px; margin-bottom: 10px; display: block; }
.tool-card h3 { font-size: 18px; margin-bottom: 6px; }
.tool-card p { color: var(--text-dim); font-size: 14px; }

/* ---------- 弹窗 ---------- */
.modal-mask {
  position: fixed; inset: 0; background: rgba(2, 6, 14, 0.78); z-index: 200;
  display: flex; align-items: center; justify-content: center; padding: 20px;
}
.modal {
  background: var(--bg-panel-solid); border: 1px solid var(--border-glow); border-radius: var(--radius-lg);
  padding: 28px; width: 100%; max-width: 420px; box-shadow: var(--shadow-neon);
}
.modal h3 { margin-bottom: 12px; color: var(--neon-cyan); }

/* ---------- 提示消息 ---------- */
.alert { padding: 12px 16px; border-radius: var(--radius-md); margin-bottom: 16px; font-size: 14px; }
.alert-error { background: rgba(255, 80, 80, .1); border: 1px solid rgba(255, 80, 80, .4); color: #ff8f8f; }
.alert-ok { background: rgba(74, 222, 128, .1); border: 1px solid rgba(74, 222, 128, .4); color: #86efac; }

/* ---------- 后台布局 ---------- */
.admin-layout { display: flex; min-height: 100vh; }
.admin-sidebar {
  width: 220px; background: var(--bg-panel-solid); border-right: 1px solid var(--border-glow);
  padding: 22px 14px; flex-shrink: 0;
}
.admin-sidebar a { display: block; padding: 10px 14px; border-radius: 10px; color: var(--text-main); font-size: 14px; margin-bottom: 4px; }
.admin-sidebar a:hover, .admin-sidebar a.active { background: rgba(0, 229, 255, 0.12); color: var(--neon-cyan); }
.admin-main { flex: 1; padding: 28px; }
.stat-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; margin-bottom: 24px; }
.stat-card { padding: 18px; }
.stat-card .num { font-size: 30px; font-weight: 800; color: var(--neon-cyan); }
.stat-card .label { color: var(--text-dim); font-size: 13px; }
.chart-box { background: var(--bg-panel); border: 1px solid var(--border-glow); border-radius: var(--radius-lg); padding: 18px; margin-bottom: 20px; }
.chart-box h4 { margin-bottom: 12px; color: var(--text-dim); font-size: 14px; }

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
  .navbar { flex-wrap: wrap; padding: 12px 16px; }
  .nav-links {
    display: none; width: 100%; flex-direction: column;
    background: var(--bg-panel-solid); border-radius: var(--radius-md);
    padding: 10px; border: 1px solid var(--border-glow);
  }
  .nav-links.open { display: flex; }
  .hamburger { display: inline-block; }
  .admin-layout { flex-direction: column; }
  .admin-sidebar { width: 100%; border-right: none; border-bottom: 1px solid var(--border-glow); }
  .container { padding: 24px 14px 40px; }
}