/* --- Sleek Dark & Glassmorphism Design System --- */
/*
 * 테마 색상은 CSS 변수로 통합 관리한다.
 * :root = 다크 테마(기본 상수), [data-theme="light"] = 라이트 테마 오버라이드.
 * data-theme 속성은 js/theme.js가 <html> 요소에 설정한다.
 * 색상 하드코딩 금지 — 반드시 아래 시맨틱 변수를 사용할 것.
 */
:root {
    /* 배경 / 표면 */
    --bg-dark: #0b0f19;
    --bg-card: #151c2c;
    --border-color: rgba(255, 255, 255, 0.08);
    --border-focus: #3b82f6;

    /* 텍스트 */
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --text-muted: #6b7280;

    /* 강조색 (accent) */
    --accent-blue: #3b82f6;
    --accent-blue-hover: #2563eb;
    --accent-blue-glow: rgba(59, 130, 246, 0.35);
    --accent-green: #10b981;
    --accent-green-glow: rgba(16, 185, 129, 0.35);
    --accent-red: #ef4444;
    --accent-red-glow: rgba(239, 68, 68, 0.35);
    --accent-orange: #f59e0b;
    --accent-blue-soft: #60a5fa;      /* 밝은 블루 텍스트 (plan.html 등) */
    --accent-red-soft: #f87171;       /* 밝은 레드 텍스트 (plan.html 등) */

    /* 시맨틱 오버레이 / 상태 (테마별로 명암 반전) */
    --overlay-subtle: rgba(255, 255, 255, 0.02);   /* 아주 옅은 표면 틴트 */
    --overlay-hover: rgba(255, 255, 255, 0.05);     /* hover / 입력 배경 */
    --overlay-strong: rgba(255, 255, 255, 0.08);    /* 강한 hover / focus 배경 */
    --overlay-border: rgba(255, 255, 255, 0.15);    /* 강조 테두리 */
    --nav-active-bg: rgba(59, 130, 246, 0.15);      /* 활성 메뉴 배경 */
    --card-shadow: rgba(0, 0, 0, 0.2);              /* 카드 hover 그림자 */
    --modal-backdrop: rgba(8, 15, 30, 0.82);        /* 모달 뒷배경 */
    --modal-bg: #111827;                            /* 모달 본체 배경 */
    --text-on-accent: #ffffff;                      /* accent 위 텍스트(버튼 등) */
    --toggle-off-bg: #374151;                       /* 토글 OFF 배경 */
    --danger-solid: #dc2626;                        /* 삭제 버튼 등 솔리드 위험색 */
    --badge-green-bg: rgba(16, 185, 129, 0.1);
    --badge-green-border: rgba(16, 185, 129, 0.2);
    --badge-red-bg: rgba(239, 68, 68, 0.1);
    --badge-red-border: rgba(239, 68, 68, 0.2);

    --sidebar-width: 260px;
    --sidebar-collapsed-width: 70px;

    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

/* --- Light Theme (기본값) --- */
/*
 * 완전한 순백이 아니라 은은한 블루-그레이 톤을 사용해
 * 다크 테마(남색 계열)와 통일감을 준다.
 */
[data-theme="light"] {
    --bg-dark: #eef1f6;        /* 페이지 배경: 옅은 블루-그레이 */
    --bg-card: #ffffff;        /* 카드/사이드바: 흰색 표면 */
    --border-color: rgba(15, 23, 42, 0.10);
    --border-focus: #3b82f6;

    --text-primary: #1e293b;   /* 진한 슬레이트 */
    --text-secondary: #64748b;
    --text-muted: #94a3b8;

    --accent-blue: #3b82f6;
    --accent-blue-hover: #2563eb;
    --accent-blue-glow: rgba(59, 130, 246, 0.25);
    --accent-green: #059669;
    --accent-green-glow: rgba(16, 185, 129, 0.25);
    --accent-red: #dc2626;
    --accent-red-glow: rgba(239, 68, 68, 0.25);
    --accent-orange: #d97706;
    --accent-blue-soft: #2563eb;
    --accent-red-soft: #dc2626;

    /* 오버레이는 어두운 색 기반으로 반전 (밝은 배경 위에서 보이도록) */
    --overlay-subtle: rgba(15, 23, 42, 0.02);
    --overlay-hover: rgba(15, 23, 42, 0.04);
    --overlay-strong: rgba(15, 23, 42, 0.07);
    --overlay-border: rgba(15, 23, 42, 0.14);
    --nav-active-bg: rgba(59, 130, 246, 0.12);
    --card-shadow: rgba(15, 23, 42, 0.10);
    --modal-backdrop: rgba(15, 23, 42, 0.45);
    --modal-bg: #ffffff;
    --text-on-accent: #ffffff;
    --toggle-off-bg: #cbd5e1;
    --danger-solid: #dc2626;
    --badge-green-bg: rgba(5, 150, 105, 0.12);
    --badge-green-border: rgba(5, 150, 105, 0.28);
    --badge-red-bg: rgba(220, 38, 38, 0.10);
    --badge-red-border: rgba(220, 38, 38, 0.24);
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-family);
    display: flex;
    min-height: 100vh;
    overflow-x: hidden;
}

/* --- Layout --- */
.app-container {
    display: flex;
    width: 100%;
}

/* --- Sidebar --- */
aside.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-card);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: fixed;
    left: 0;
    top: 0;
    z-index: 100;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.sidebar-brand {
    padding: 24px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-bottom: 1px solid var(--border-color);
}

.brand-icon {
    font-size: 24px;
}

.brand-name {
    font-size: 18px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent-blue-soft), var(--accent-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.5px;
}

.nav-links {
    list-style: none;
    padding: 20px 12px;
    flex-grow: 1;
    overflow-y: auto;
}

.nav-links li {
    margin-bottom: 8px;
}

.nav-item-link {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 12px 16px;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.nav-item-link:hover {
    background-color: var(--overlay-hover);
    color: var(--text-primary);
}

.nav-item-link.active {
    background-color: var(--nav-active-bg);
    color: var(--accent-blue);
    font-weight: 600;
    border-left: 3px solid var(--accent-blue);
}

.nav-icon {
    font-size: 18px;
}

.nav-text {
    font-size: 14px;
}

.sidebar-footer {
    padding: 20px;
    border-top: 1px solid var(--border-color);
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 12px;
}

.user-avatar {
    font-size: 24px;
    background: var(--overlay-hover);
    padding: 8px;
    border-radius: 50%;
}

.user-info {
    display: flex;
    flex-direction: column;
}

.user-name {
    font-size: 14px;
    font-weight: 600;
}

.user-role {
    font-size: 11px;
    color: var(--text-muted);
}

/* --- Main Content Area --- */
main.main-content {
    margin-left: var(--sidebar-width);
    width: calc(100% - var(--sidebar-width));
    flex-grow: 1;
    padding: 40px;
    min-height: 100vh;
    transition: margin-left 0.3s ease;
    min-width: 0;
}

header.content-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.page-title h1 {
    font-size: 26px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.page-title p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: 4px;
}

/* --- Responsive Layout (Grid) --- */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 30px;
}

.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 24px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px var(--card-shadow);
    border-color: var(--overlay-border);
}

/* --- Status Badges --- */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 10px;
    border-radius: 9999px;
    font-size: 12px;
    font-weight: 600;
}

.badge-online {
    background-color: var(--badge-green-bg);
    color: var(--accent-green);
    border: 1px solid var(--badge-green-border);
}

.badge-offline {
    background-color: var(--badge-red-bg);
    color: var(--accent-red);
    border: 1px solid var(--badge-red-border);
}

/* --- CSS Forms & UI Kit --- */
.btn {
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    border: none;
    transition: all 0.2s ease;
}

.btn-primary {
    background-color: var(--accent-blue);
    color: var(--text-on-accent);
}

.btn-primary:hover {
    background-color: var(--accent-blue-hover);
    box-shadow: 0 0 12px var(--accent-blue-glow);
}

/* --- Common Form Inputs & Selects --- */
.form-group {
    margin-bottom: 16px;
}
.form-group label {
    display: block;
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 6px;
    font-weight: 600;
}
.form-control {
    background-color: var(--overlay-hover) !important;
    border: 1px solid var(--border-color) !important;
    color: var(--text-primary) !important;
    padding: 10px 14px !important;
    border-radius: 8px !important;
    font-size: 14px !important;
    width: 100% !important;
    transition: all 0.2s ease !important;
}
.form-control:focus {
    outline: none !important;
    border-color: var(--border-focus) !important;
    background-color: var(--overlay-strong) !important;
}
select.form-control {
    appearance: none !important;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%239ca3af' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E") !important;
    background-repeat: no-repeat !important;
    background-position: right 14px center !important;
    background-size: 16px !important;
    padding-right: 40px !important;
}
select.form-control option {
    background-color: var(--bg-card) !important;
    color: var(--text-primary) !important;
}
/* 라이트 테마에서 select 화살표 색을 밝은 배경에 맞게 어둡게 */
[data-theme="light"] select.form-control {
    background-image: url("data:image/svg+xml;charset=UTF-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E") !important;
}

/* --- Responsive Media Queries --- */
@media (max-width: 1200px) {
    .dashboard-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    aside.sidebar {
        width: var(--sidebar-collapsed-width);
    }
    .brand-name, .nav-text, .user-info {
        display: none;
    }
    main.main-content {
        margin-left: var(--sidebar-collapsed-width);
        padding: 20px;
    }
    .dashboard-grid {
        grid-template-columns: 1fr;
    }
}
