/* ================= 云阅电子书 后台样式 - 全面优化版 ================= */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --primary: #4f6ef7;
    --primary-dark: #3b5de7;
    --primary-light: #eef2ff;
    --primary-gradient: linear-gradient(135deg, #4f6ef7 0%, #7c5cfc 50%, #a855f7 100%);
    --danger: #ef4444;
    --danger-light: #fef2f2;
    --success: #10b981;
    --success-light: #ecfdf5;
    --bg: #f0f2f8;
    --bg-card: #ffffff;
    --text: #1a1a2e;
    --text-light: #6b7294;
    --border: #e8eaf3;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 2px 12px rgba(79,110,247,0.06);
    --transition: all .3s cubic-bezier(.4,0,.2,1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    font-size: 14px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
.link { color: var(--primary); cursor: pointer; background: none; border: none; font-size: 13px; transition: var(--transition); }
.link:hover { text-decoration: underline; opacity: 0.85; }

/* ---------- 登录页 ---------- */
.login-body {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-gradient);
    padding: 20px;
    position: relative;
    overflow: hidden;
}
.login-body::before {
    content: '';
    position: absolute;
    width: 500px; height: 500px;
    border-radius: 50%;
    background: rgba(255,255,255,0.08);
    top: -100px; right: -100px;
}
.login-body::after {
    content: '';
    position: absolute;
    width: 400px; height: 400px;
    border-radius: 50%;
    background: rgba(255,255,255,0.06);
    bottom: -80px; left: -80px;
}
.login-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 44px 36px;
    width: 100%;
    max-width: 420px;
    box-shadow: 0 24px 64px rgba(0,0,0,0.2);
    position: relative;
    z-index: 1;
}
.login-logo { text-align: center; margin-bottom: 32px; }
.login-logo-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px; height: 56px;
    background: var(--primary-gradient);
    color: #fff;
    font-size: 26px;
    font-weight: 700;
    border-radius: 16px;
    margin-bottom: 12px;
    box-shadow: 0 8px 24px rgba(79,110,247,0.3);
}
.login-logo h1 { font-size: 22px; font-weight: 700; letter-spacing: -0.5px; }
.login-logo p { color: var(--text-light); font-size: 13px; margin-top: 6px; }
.login-tip { text-align: center; color: var(--text-light); font-size: 12px; margin-top: 20px; }
.login-back { text-align: center; margin-top: 10px; }
.login-back a { color: var(--primary); font-size: 13px; }

/* ---------- 布局 ---------- */
.admin-body { display: flex; min-height: 100vh; }

.sidebar {
    width: 220px;
    background: linear-gradient(180deg, #1a1a2e 0%, #16213e 100%);
    color: #cbd5e1;
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0; bottom: 0; left: 0;
    z-index: 10;
    box-shadow: 4px 0 24px rgba(0,0,0,0.1);
}
.sidebar-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 20px 18px;
    font-size: 16px;
    font-weight: 700;
    color: #fff;
    border-bottom: 1px solid rgba(255,255,255,0.08);
}
.sidebar-logo .logo-icon {
    width: 36px; height: 36px;
    background: var(--primary-gradient);
    border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    font-size: 17px;
    box-shadow: 0 4px 12px rgba(79,110,247,0.3);
}
.sidebar-nav { flex: 1; padding: 16px 0; }
.sidebar-nav a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 13px 20px;
    color: #94a3b8;
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
    border-left: 3px solid transparent;
    margin: 2px 8px 2px 0;
    border-radius: 0 8px 8px 0;
}
.sidebar-nav a:hover { background: rgba(255,255,255,0.06); color: #fff; }
.sidebar-nav a.active {
    background: rgba(79,110,247,0.2);
    color: #fff;
    border-left-color: var(--primary);
}
.sidebar-footer { padding: 16px 18px; border-top: 1px solid rgba(255,255,255,0.08); display: flex; flex-direction: column; gap: 6px; }
.sidebar-footer a {
    color: #64748b;
    font-size: 13px;
    padding: 8px 10px;
    border-radius: 8px;
    transition: var(--transition);
}
.sidebar-footer a:hover { color: #fff; background: rgba(255,255,255,0.06); }

.main-area {
    flex: 1;
    margin-left: 220px;
    min-width: 0;
}
.main-header {
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(0,0,0,0.04);
    padding: 18px 28px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 5;
}
.main-header h2 { font-size: 20px; font-weight: 700; letter-spacing: -0.5px; }
.main-header-right { display: flex; align-items: center; gap: 16px; }
.welcome { color: var(--text-light); font-size: 13px; }
.mobile-logout { display: none; }

.main-content { padding: 28px; }

/* ---------- 仪表盘 ---------- */
.stat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(190px, 1fr));
    gap: 16px;
    margin-bottom: 28px;
}
.stat-card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 24px 20px;
    box-shadow: var(--shadow);
    text-align: center;
    border: 1px solid rgba(0,0,0,0.03);
    transition: var(--transition);
}
.stat-card:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(79,110,247,0.08); }
.stat-num {
    font-size: 34px;
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.stat-label { color: var(--text-light); font-size: 13px; margin-top: 6px; font-weight: 500; }

.panel {
    background: var(--bg-card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px;
    margin-bottom: 24px;
    border: 1px solid rgba(0,0,0,0.03);
}
.panel-title {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--border);
    letter-spacing: -0.3px;
}
.quick-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.quick-btn {
    display: inline-block;
    padding: 12px 22px;
    background: var(--primary-light);
    color: var(--primary);
    border: 1px solid #c7d2fe;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 600;
    transition: var(--transition);
}
.quick-btn:hover {
    background: var(--primary-gradient);
    color: #fff;
    border-color: transparent;
    box-shadow: 0 4px 16px rgba(79,110,247,0.25);
    transform: translateY(-1px);
}

/* ---------- 表格 ---------- */
.table { width: 100%; border-collapse: collapse; }
.table th {
    text-align: left;
    padding: 12px 14px;
    background: #f8f9fc;
    color: var(--text-light);
    font-size: 12px;
    font-weight: 600;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.table td {
    padding: 12px 14px;
    border-bottom: 1px solid var(--border);
    font-size: 13px;
    vertical-align: middle;
}
.table tr:hover td { background: #f8f9fc; }
.table tr:last-child td { border-bottom: none; }
.table-empty { text-align: center; color: var(--text-light); padding: 48px 14px !important; }
.td-title { font-weight: 600; max-width: 260px; }
.td-actions { white-space: nowrap; }

/* ---------- 徽章 ---------- */
.badge {
    display: inline-block;
    padding: 3px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.3px;
}
.badge-pdf { background: #fef2f2; color: #dc2626; }
.badge-text { background: #eff2ff; color: #4f6ef7; }
.badge-on { background: #ecfdf5; color: #059669; }
.badge-off { background: #f3f4f6; color: #9ca3af; }

/* ---------- 表单 ---------- */
.book-form { max-width: 760px; }
.form-row { display: flex; gap: 16px; }
.form-row .form-group { flex: 1; }
.form-group { margin-bottom: 18px; }
.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text);
}
.form-group input[type="text"],
.form-group input[type="password"],
.form-group input[type="number"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    outline: none;
    transition: var(--transition);
    font-family: inherit;
    background: var(--bg-card);
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79,110,247,0.1);
}
.form-group textarea { resize: vertical; min-height: 100px; }
.form-group input[type="file"] { font-size: 13px; }
.form-tip { color: var(--text-light); font-size: 12px; margin-top: 8px; }
.checkbox-label { display: flex !important; align-items: center; gap: 8px; font-weight: 400 !important; cursor: pointer; }
.checkbox-label input { width: 18px; height: 18px; accent-color: var(--primary); }
.form-actions { display: flex; gap: 12px; margin-top: 24px; }

.input-sm {
    padding: 7px 10px !important;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 13px;
    width: auto !important;
    transition: var(--transition);
}
.input-sm:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,110,247,0.1); }

/* ---------- 按钮 ---------- */
.btn {
    display: inline-block;
    padding: 9px 18px;
    border: 1.5px solid var(--border);
    background: var(--bg-card);
    color: var(--text);
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    line-height: 1.5;
}
.btn:hover { border-color: var(--primary); color: var(--primary); }
.btn-primary {
    background: var(--primary-gradient);
    border-color: transparent;
    color: #fff;
    box-shadow: 0 2px 8px rgba(79,110,247,0.25);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 4px 16px rgba(79,110,247,0.35); color: #fff; border-color: transparent; }
.btn-danger { color: var(--danger); border-color: #fecaca; }
.btn-danger:hover { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn-block { width: 100%; padding: 12px; font-size: 15px; font-weight: 600; }
.btn-sm { padding: 6px 14px; font-size: 12px; }

/* ---------- 提示 ---------- */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    margin-bottom: 18px;
    font-weight: 500;
}
.alert-success { background: var(--success-light); color: #059669; border: 1px solid #a7f3d0; }
.alert-error { background: var(--danger-light); color: #dc2626; border: 1px solid #fecaca; }

/* ---------- 工具栏 ---------- */
.panel-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}
.toolbar-form { display: flex; gap: 8px; }
.toolbar-form input[type="text"] {
    padding: 8px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    outline: none;
    width: 220px;
    transition: var(--transition);
}
.toolbar-form input[type="text"]:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,110,247,0.1); }
.inline-form { display: inline-flex; align-items: center; gap: 6px; flex-wrap: wrap; }

/* ================ 手机端响应式 ================ */
@media (max-width: 768px) {
    .sidebar {
        width: 100%;
        height: auto;
        position: fixed;
        bottom: 0;
        top: auto;
        flex-direction: row;
        z-index: 200;
        box-shadow: 0 -4px 24px rgba(0,0,0,0.1);
    }
    .sidebar-logo { display: none; }
    .sidebar-nav {
        flex: 1;
        display: flex;
        padding: 0;
        overflow-x: auto;
    }
    .sidebar-nav a {
        flex: 1;
        justify-content: center;
        padding: 10px 6px;
        font-size: 11px;
        border-left: none;
        border-radius: 0;
        margin: 0;
        flex-direction: column;
        gap: 3px;
        text-align: center;
        min-width: 0;
    }
    .sidebar-nav a .nav-icon {
        font-size: 18px;
        line-height: 1;
    }
    .sidebar-nav a .nav-label {
        font-size: 10px;
    }
    .sidebar-nav a.active {
        background: rgba(79,110,247,0.25);
        border-left: none;
        border-top: 2px solid var(--primary);
    }
    .sidebar-footer { display: none; }

    .main-area {
        margin-left: 0;
        padding-bottom: 72px;
    }
    .main-header { padding: 14px 16px; }
    .main-header h2 { font-size: 17px; }
    .main-content { padding: 16px; }
    .mobile-logout { display: inline-block !important; }
    .welcome { display: none; }

    .stat-grid { grid-template-columns: repeat(3, 1fr); gap: 10px; }
    .stat-card { padding: 16px 12px; }
    .stat-num { font-size: 24px; }
    .stat-label { font-size: 11px; }

    .form-row { flex-direction: column; gap: 0; }
    .panel { padding: 16px; }

    .toolbar-form input[type="text"] { width: 160px; }
    .panel-toolbar { flex-direction: column; align-items: stretch; }
    .toolbar-form { width: 100%; }
    .toolbar-form input[type="text"] { flex: 1; width: auto; }

    /* 表格在手机端可横向滚动 */
    .panel { overflow-x: auto; }
    .table { min-width: 640px; }

    .quick-actions { gap: 8px; }
    .quick-btn { padding: 10px 16px; font-size: 13px; }
}

@media (max-width: 400px) {
    .stat-grid { grid-template-columns: repeat(2, 1fr); }
    .login-card { padding: 32px 20px; }
}