/* ==========================================================================
   CSS 設計系統 - 現代深色科技風 (Dark Premium Aesthetic)
   ========================================================================== */

/* 全域 CSS 變數定義 */
:root {
    --bg-dark: #0f172a;       /* 深石板藍底色 */
    --bg-card: #1e293b;       /* 卡片底色 */
    --primary: #6366f1;       /* 靛藍色 (主色調) */
    --primary-hover: #4f46e5; /* 靛藍懸停 */
    --secondary: #64748b;     /* 次要灰色 */
    --success: #10b981;       /* 綠色 (新增/成功) */
    --success-hover: #059669; /* 綠色懸停 */
    --danger: #ef4444;        /* 紅色 (刪除/危險) */
    --danger-hover: #dc2626;  /* 紅色懸停 */
    
    --text-primary: #f8fafc;  /* 主要文字 (亮白) */
    --text-muted: #94a3b8;    /* 次要文字 (淡灰) */
    --border-color: #334155;  /* 邊框線條 */
    --glass-bg: rgba(30, 41, 59, 0.7); /* 玻璃擬物背景 */
    
    --font-sans: 'Outfit', 'Noto Sans TC', system-ui, sans-serif;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius: 12px;
    --shadow-sm: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-md: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 20px 25px -5px rgb(0 0 0 / 0.15), 0 8px 10px -6px rgb(0 0 0 / 0.15);
}

/* 基礎重設 (Reset) */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    background-image: 
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(16, 185, 129, 0.1) 0px, transparent 50%);
    background-attachment: fixed;
}

/* 主要網頁容器 */
.app-container {
    width: 100%;
    max-width: 1200px;
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* 頁首樣式 */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
}

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

.logo .icon {
    font-size: 1.8rem;
    filter: drop-shadow(0 0 8px var(--primary));
}

.logo h1 {
    font-size: 1.4rem;
    font-weight: 700;
    background: linear-gradient(135deg, #fff 0%, var(--text-muted) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.5px;
}

/* 頂部會員歡迎區 */
.auth-header-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.user-display {
    color: var(--text-muted);
    font-weight: 500;
    background: rgba(255, 255, 255, 0.05);
    padding: 0.35rem 0.75rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
}

#username-display {
    color: var(--text-primary);
    font-weight: 600;
}

/* 主要內容區域 */
.app-main {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* 卡片通用樣式 (Glassmorphism Effect) */
.card {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: var(--shadow-lg);
}

.card-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.card-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card-subtitle {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

.card-body {
    padding: 1.5rem;
}

/* 會員驗證卡片特定樣式 */
.auth-card {
    max-width: 450px;
    margin: 2rem auto;
    width: 100%;
}

.auth-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
}

.tab-btn {
    flex: 1;
    background: none;
    border: none;
    padding: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-sans);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border-bottom: 2px solid transparent;
}

.tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

/* 庫存雙欄位排版 */
.inventory-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

@media (min-width: 900px) {
    .inventory-container {
        grid-template-columns: 350px 1fr;
    }
}

/* 表單元件樣式 */
.form-group {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

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

.input-wrapper {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.input-wrapper label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-muted);
}

.input-wrapper input {
    background-color: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.75rem;
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    transition: var(--transition);
}

.input-wrapper input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 0.5rem;
}

/* 按鈕樣式 */
.btn {
    font-family: var(--font-sans);
    font-weight: 600;
    font-size: 0.95rem;
    padding: 0.75rem 1.25rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    justify-content: center;
    align-items: center;
    gap: 0.5rem;
    text-align: center;
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, #4f46e5 100%);
    color: white;
    box-shadow: 0 4px 10px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    background: linear-gradient(135deg, #4f46e5 0%, #4338ca 100%);
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
    background-color: var(--secondary);
    color: white;
}

.btn-secondary:hover {
    background-color: #475569;
}

.btn-success {
    background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
    color: white;
    box-shadow: 0 4px 10px rgba(16, 185, 129, 0.2);
}

.btn-success:hover {
    background: linear-gradient(135deg, #059669 0%, #047857 100%);
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(16, 185, 129, 0.3);
}

.btn-danger {
    background-color: rgba(239, 68, 68, 0.15);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #f87171;
}

.btn-danger:hover {
    background-color: var(--danger);
    color: white;
    border-color: var(--danger);
}

.btn-sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.8rem;
    border-radius: 6px;
}

.btn-icon {
    background: none;
    border: none;
    font-size: 1rem;
    cursor: pointer;
    color: var(--text-muted);
    padding: 0.35rem;
    border-radius: 6px;
}

.btn-icon:hover {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

/* 庫存列表樣式 */
.list-card {
    height: 100%;
}

.list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.table-responsive {
    width: 100%;
    overflow-x: auto;
}

.inventory-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.95rem;
}

.inventory-table th,
.inventory-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.inventory-table th {
    font-weight: 600;
    color: var(--text-muted);
    background-color: rgba(15, 23, 42, 0.3);
}

.inventory-table tbody tr {
    transition: var(--transition);
}

.inventory-table tbody tr:hover {
    background-color: rgba(255, 255, 255, 0.02);
}

.text-center {
    text-align: center;
}

.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-info {
    background-color: rgba(99, 102, 241, 0.15);
    color: #818cf8;
    border: 1px solid rgba(99, 102, 241, 0.3);
}

.badge-warning {
    background-color: rgba(245, 158, 11, 0.15);
    color: #fbbf24;
    border: 1px solid rgba(245, 158, 11, 0.3);
}

/* 操作按鈕組 */
.action-buttons {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
}

/* 載入中動畫 */
.loading-spinner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 0;
    gap: 1rem;
    color: var(--text-muted);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(99, 102, 241, 0.1);
    border-left-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 空白狀態 */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 4rem 1rem;
    color: var(--text-muted);
    text-align: center;
    gap: 1rem;
}

.empty-icon {
    font-size: 3rem;
    filter: grayscale(0.5);
    opacity: 0.7;
}

/* 頁尾樣式 */
.app-footer {
    text-align: center;
    padding: 2rem 0 1rem;
    font-size: 0.8rem;
    color: var(--text-muted);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* 工具類別 (Utility Classes) */
.hidden {
    display: none !important;
}

/* 提示訊息 CSS (動畫滑入) */
.toast-msg {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background-color: var(--bg-card);
    border-left: 4px solid var(--primary);
    color: var(--text-primary);
    padding: 1rem 1.5rem;
    border-radius: 6px;
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    z-index: 3000;
    animation: slideIn 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.toast-msg.success {
    border-left-color: var(--success);
}

.toast-msg.error {
    border-left-color: var(--danger);
}

@keyframes slideIn {
    from {
        transform: translateY(100px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}