/* ==========================================================================
   全域變數與主題設定
   ========================================================================== */
:root {
    /* 暗色模式變數 (預設) */
    --bg-gradient: radial-gradient(circle at 50% 50%, #1a2333 0%, #0d1117 100%);
    --text-color: #ecf0f1;
    --text-muted: #8b949e;
    --panel-bg: rgba(255, 255, 255, 0.03);
    --panel-border: rgba(255, 255, 255, 0.08);
    --panel-shadow: rgba(0, 0, 0, 0.37);
    --card-title: #ffffff;
    --accent-gold: #D4AF37;
    --accent-cyan: #00F2FE;
    --sidebar-width: 260px;
}

[data-theme="light"] {
    /* 亮色模式變數 */
    --bg-gradient: radial-gradient(circle at 50% 50%, #f4f7f6 0%, #e2e8f0 100%);
    --text-color: #2c3e50;
    --text-muted: #64748b;
    --panel-bg: rgba(255, 255, 255, 0.45);
    --panel-border: rgba(0, 0, 0, 0.08);
    --panel-shadow: rgba(148, 163, 184, 0.15);
    --card-title: #0f172a;
    --accent-gold: #b58900;
    --accent-cyan: #0284c7;
}

/* ==========================================================================
   全域基礎設定
   ========================================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'SF Pro Display', '-apple-system', 'Segoe UI', 'Roboto', monospace;
}

body {
    background: var(--bg-gradient);
    color: var(--text-color);
    min-height: 100vh;
    overflow-x: hidden;
    transition: background 0.5s ease, color 0.3s ease;
}

/* 磨砂玻璃通用效果 */
.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--panel-border);
    border-radius: 16px;
    box-shadow: 0 8px 32px 0 var(--panel-shadow);
    transition: all 0.3s ease;
}

/* ==========================================================================
   版面佈局 (Layout)
   ========================================================================== */
.app-container {
    display: flex;
    min-height: 100vh;
    width: 100%;
}

/* 左側選單樣式 */
.sidebar-menu {
    width: var(--sidebar-width);
    flex-shrink: 0;
    margin: 1.5rem 0 1.5rem 1.5rem;
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
    height: calc(100vh - 3rem);
    position: sticky;
    top: 1.5rem;
}

/* 右側主要內容包覆區 */
.main-content {
    flex-grow: 1;
    padding: 1.5rem 2rem;
    display: flex;
    flex-direction: column;
    max-width: calc(100% - var(--sidebar-width));
}

/* 頂部導航 */
header {
    width: 100%;
    padding: 1.2rem 2rem;
    margin-bottom: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

main {
    width: 100%;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 1.5rem;
    flex-grow: 1;
}

/* ==========================================================================
   元件與細部樣式
   ========================================================================== */
/* Logo 區域 */
.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 22px;
    height: 22px;
    border: 2px solid var(--accent-gold);
    transform: rotate(45deg);
    box-shadow: 0 0 8px var(--accent-gold);
}

.logo-text {
    font-size: 1.2rem;
    font-weight: 600;
    letter-spacing: 2px;
    color: var(--card-title);
}

.system-title-text {
    font-size: 1rem;
    font-weight: 500;
    letter-spacing: 1px;
    color: var(--text-muted);
}

/* 導航連結 */
.nav-links {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.nav-item {
    text-decoration: none;
    color: var(--text-muted);
    padding: 0.8rem 1.2rem;
    border-radius: 8px;
    font-size: 0.95rem;
    transition: all 0.3s ease;
}

.nav-item:hover, .nav-item.active {
    background: var(--panel-border);
    color: var(--card-title);
    padding-left: 1.5rem;
}

.nav-item.active {
    border-left: 3px solid var(--accent-cyan);
}

/* 系統狀態與按鈕 */
.system-status {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 0.85rem;
    color: var(--text-muted);
}

.status-dot {
    width: 8px;
    height: 8px;
    background-color: var(--accent-cyan);
    border-radius: 50%;
    box-shadow: 0 0 8px var(--accent-cyan);
    animation: pulse 2s infinite;
}

/* 主題切換按鈕 */
.theme-btn {
    background: var(--panel-border);
    border: none;
    outline: none;
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    transition: transform 0.2s ease, background 0.3s ease;
}

.theme-btn:hover {
    transform: scale(1.1);
}

/* 內頁卡片細節 */
.primary-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.hero-card {
    padding: 2.5rem;
    position: relative;
    overflow: hidden;
}

.hero-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(to bottom, var(--accent-gold), var(--accent-cyan));
}

.hero-tag {
    font-size: 0.8rem;
    color: var(--accent-gold);
    letter-spacing: 3px;
    text-transform: uppercase;
    margin-bottom: 0.5rem;
}

.hero-title {
    font-size: 2rem;
    font-weight: 300;
    letter-spacing: 1px;
    margin-bottom: 1rem;
    color: var(--card-title);
}

.section-title {
    font-size: 0.9rem;
    color: var(--text-muted);
    letter-spacing: 2px;
    margin-top: 0.5rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.section-title::after {
    content: '';
    flex-grow: 1;
    height: 1px;
    background: var(--panel-border);
}

/* 傳送節點矩陣 */
.portal-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.2rem;
}

.portal-item {
    text-decoration: none;
    color: inherit;
    padding: 1.8rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: relative;
    cursor: pointer;
    min-height: 160px;
}

.portal-item::after {
    content: '→';
    position: absolute;
    right: 1.5rem;
    bottom: 1.5rem;
    font-size: 1.2rem;
    color: var(--text-muted);
    transition: all 0.3s ease;
    opacity: 0.5;
}

.portal-item:hover {
    border-color: var(--accent-cyan);
    box-shadow: 0 8px 32px 0 rgba(0, 242, 254, 0.12);
    transform: translateY(-2px);
}

.portal-item:hover::after {
    color: var(--accent-cyan);
    opacity: 1;
    transform: translateX(4px);
}

.portal-name {
    font-size: 1.1rem;
    font-weight: 400;
    color: var(--card-title);
    margin-bottom: 0.4rem;
    letter-spacing: 1px;
}

.portal-alias {
    font-size: 0.75rem;
    color: var(--accent-gold);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.portal-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
    line-height: 1.5;
    padding-right: 1.5rem;
}

/* 側邊欄與日誌 */
.sidebar-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.clock-card {
    padding: 1.5rem;
    text-align: center;
}

#clock {
    font-size: 2rem;
    font-weight: 300;
    letter-spacing: 2px;
    color: var(--card-title);
    margin-top: 0.5rem;
}

.log-card {
    padding: 1.5rem;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.log-title {
    font-size: 0.9rem;
    color: var(--accent-gold);
    letter-spacing: 1px;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--panel-border);
    padding-bottom: 0.5rem;
}

.log-list {
    list-style: none;
    font-size: 0.8rem;
    color: var(--text-muted);
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.log-item {
    display: flex;
    gap: 12px;
    line-height: 1.4;
}

.log-time {
    color: var(--accent-cyan);
    flex-shrink: 0;
}

footer {
    margin-top: auto;
    padding-top: 2rem;
    font-size: 0.75rem;
    color: var(--text-muted);
    letter-spacing: 1px;
}

/* ==========================================================================
   動畫與響應式斷點
   ========================================================================== */
@keyframes pulse {
    0% { opacity: 0.4; }
    50% { opacity: 1; box-shadow: 0 0 12px var(--accent-cyan); }
    100% { opacity: 0.4; }
}

@media (max-width: 1024px) {
    .sidebar-menu {
        display: none; /* 在中小型螢幕隱藏側邊選單，可依需求改為漢堡選單 */
    }
    .main-content {
        max-width: 100%;
    }
}

@media (max-width: 850px) {
    main {
        grid-template-columns: 1fr;
    }
}