/* --- Premium Design System Tokens --- */
:root {
    /* Color Palette - Dark Theme (Default) */
    --bg-primary: #08090e;
    --bg-secondary: #0f111a;
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --accent-color: #6366f1; /* Indigo */
    --accent-hover: #4f46e5;
    --accent-glow: rgba(99, 102, 241, 0.25);
    
    /* Card Tokens */
    --card-bg: rgba(17, 20, 32, 0.55);
    --card-border: rgba(255, 255, 255, 0.06);
    --card-hover-border: rgba(99, 102, 241, 0.3);
    --card-shadow: rgba(0, 0, 0, 0.4);
    --card-title-color: #ffffff;
    
    /* Interactive Colors */
    --cpu-glow: rgba(59, 130, 246, 0.15);
    --cpu-color: #3b82f6;
    --ram-glow: rgba(168, 85, 247, 0.15);
    --ram-color: #a855f7;
    --disk-glow: rgba(16, 185, 129, 0.15);
    --disk-color: #10b981;
    --net-glow: rgba(245, 158, 11, 0.15);
    --net-color: #f59e0b;
    
    --gauge-bg: rgba(255, 255, 255, 0.05);
    --navbar-bg: rgba(8, 9, 14, 0.75);
    --transition-speed: 0.3s;
    --font-heading: 'Outfit', 'Noto Sans KR', sans-serif;
    --font-body: 'Inter', 'Noto Sans KR', sans-serif;
}

[data-theme="light"] {
    /* Color Palette - Light Theme */
    --bg-primary: #f3f4f6;
    --bg-secondary: #ffffff;
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --accent-color: #4f46e5;
    --accent-hover: #3730a3;
    --accent-glow: rgba(79, 70, 229, 0.15);
    
    /* Card Tokens */
    --card-bg: rgba(255, 255, 255, 0.75);
    --card-border: rgba(0, 0, 0, 0.08);
    --card-hover-border: rgba(79, 70, 229, 0.25);
    --card-shadow: rgba(0, 0, 0, 0.06);
    --card-title-color: #111827;
    
    /* Interactive Colors */
    --cpu-glow: rgba(59, 130, 246, 0.1);
    --cpu-color: #2563eb;
    --ram-glow: rgba(168, 85, 247, 0.1);
    --ram-color: #9333ea;
    --disk-glow: rgba(16, 185, 129, 0.1);
    --disk-color: #059669;
    --net-glow: rgba(245, 158, 11, 0.1);
    --net-color: #d97706;
    
    --gauge-bg: rgba(0, 0, 0, 0.05);
    --navbar-bg: rgba(243, 244, 246, 0.75);
}

/* --- Base Reset & Scrollbar --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-body);
    line-height: 1.6;
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow-x: hidden;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
    background: var(--card-border);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}

/* --- Interactive Particle Canvas --- */
#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    pointer-events: none;
}

/* --- Navigation Bar --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    z-index: 100;
    background-color: var(--navbar-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--card-border);
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.nav-container {
    max-width: 1200px;
    height: 100%;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--text-primary);
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
    transition: transform 0.2s ease;
}
.logo:hover {
    transform: scale(1.02);
}
.logo-icon {
    color: var(--accent-color);
    width: 24px;
    height: 24px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-item {
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color var(--transition-speed), transform 0.2s;
    display: flex;
    align-items: center;
    gap: 0.4rem;
}
.nav-item:hover {
    color: var(--text-primary);
    transform: translateY(-1px);
}

.github-link {
    background-color: var(--card-border);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    border: 1px solid transparent;
}
.github-link:hover {
    border-color: var(--accent-color);
    color: var(--accent-color) !important;
}

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

.theme-btn {
    background: none;
    border: 1px solid var(--card-border);
    padding: 0.5rem;
    border-radius: 8px;
    cursor: pointer;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s, border-color 0.2s;
}
.theme-btn:hover {
    background-color: var(--card-border);
    border-color: var(--accent-color);
}

/* Light / Dark Icon Toggling */
[data-theme="dark"] .icon-light { display: none; }
[data-theme="dark"] .icon-dark { display: block; }
[data-theme="light"] .icon-light { display: block; }
[data-theme="light"] .icon-dark { display: none; }

/* --- Hero Section --- */
.hero-section {
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 8rem 2rem 4rem;
    position: relative;
}

.hero-content {
    max-width: 800px;
    z-index: 10;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--accent-glow);
    border: 1px solid var(--accent-color);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0.4rem 1rem;
    border-radius: 100px;
    margin-bottom: 2rem;
    animation: pulse 2s infinite;
}

.badge-icon {
    width: 14px;
    height: 14px;
    color: var(--accent-color);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 4.5rem;
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: linear-gradient(135deg, #a5b4fc 0%, #6366f1 50%, #4338ca 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 650px;
    margin: 0 auto 2.5rem;
    font-weight: 400;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
}
.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background-color: var(--accent-color);
    color: #ffffff;
    box-shadow: 0 4px 15px var(--accent-glow);
}
.btn-primary:hover {
    background-color: var(--accent-hover);
    box-shadow: 0 6px 20px var(--accent-glow);
}

.btn-secondary {
    background-color: var(--card-bg);
    color: var(--text-primary);
    border: 1px solid var(--card-border);
}
.btn-secondary:hover {
    border-color: var(--accent-color);
    background-color: var(--card-border);
}

/* --- General Section Styles --- */
.section-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-badge {
    color: var(--accent-color);
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    display: block;
    margin-bottom: 0.5rem;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.section-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* --- Dashboard Section --- */
.dashboard-section {
    padding: 6rem 0;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--card-border);
    border-bottom: 1px solid var(--card-border);
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.5rem;
}

.dashboard-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.8rem;
    box-shadow: 0 8px 32px var(--card-shadow);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: transform var(--transition-speed) cubic-bezier(0.16, 1, 0.3, 1),
                border-color var(--transition-speed),
                box-shadow var(--transition-speed);
    display: flex;
    flex-direction: column;
}

.dashboard-card:hover {
    transform: translateY(-5px);
    border-color: var(--card-hover-border);
    box-shadow: 0 12px 40px rgba(99, 102, 241, 0.08);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.2rem;
}

.card-icon-container {
    width: 42px;
    height: 42px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.card-icon {
    width: 22px;
    height: 22px;
}

/* Dynamic color mappings for dashboard card icons */
.bg-cpu { background-color: var(--cpu-glow); color: var(--cpu-color); }
.bg-ram { background-color: var(--ram-glow); color: var(--ram-color); }
.bg-disk { background-color: var(--disk-glow); color: var(--disk-color); }
.bg-net { background-color: var(--net-glow); color: var(--net-color); }

.card-tag {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.2rem 0.6rem;
    border-radius: 100px;
    background-color: var(--card-border);
    color: var(--text-secondary);
}

.card-title {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: 0.4rem;
}

.card-value-wrapper {
    display: flex;
    align-items: baseline;
    margin-bottom: 1.5rem;
}

.card-value {
    font-size: 2.2rem;
    font-family: var(--font-heading);
    font-weight: 700;
    color: var(--card-title-color);
}

.card-unit {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-left: 0.3rem;
    font-weight: 500;
}

/* Gauge styling for CPU */
.gauge-container {
    position: relative;
    width: 120px;
    height: 120px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.progress-ring {
    transform: rotate(-90deg);
}

.progress-ring__background {
    stroke: var(--gauge-bg);
}

.progress-ring__circle {
    stroke: var(--cpu-color);
    stroke-linecap: round;
    transition: stroke-dashoffset 0.35s;
    transform-origin: 50% 50%;
}

.gauge-inner-text {
    position: absolute;
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--cpu-color);
    letter-spacing: 0.05em;
}

/* Linear progress bars for RAM & Disk */
.progress-bar-container {
    margin-bottom: 1.5rem;
}

.progress-bar-track {
    height: 8px;
    background-color: var(--gauge-bg);
    border-radius: 100px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--ram-color), #c084fc);
    border-radius: 100px;
    transition: width 0.5s ease-out;
}

.fill-disk {
    background: linear-gradient(90deg, var(--disk-color), #34d399);
}

.progress-bar-info {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Network & Uptime specifics */
.net-status-details {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.net-stat-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.mini-icon {
    width: 14px;
    height: 14px;
    vertical-align: middle;
    margin-right: 0.2rem;
}

.net-stat-val {
    font-weight: 600;
    color: var(--card-title-color);
}

.uptime-row {
    border-top: 1px dashed var(--card-border);
    padding-top: 0.6rem;
    margin-top: 0.2rem;
}

.font-accent {
    color: var(--net-color) !important;
}

.card-footer-text {
    font-size: 0.75rem;
    color: var(--text-secondary);
    border-top: 1px solid var(--card-border);
    padding-top: 0.8rem;
    margin-top: auto;
}

/* --- Services / Link Grid Section --- */
.services-section {
    padding: 8rem 0;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 2rem;
}

.service-card {
    position: relative;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 8px 32px var(--card-shadow);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: transform var(--transition-speed) cubic-bezier(0.16, 1, 0.3, 1),
                border-color var(--transition-speed);
}

.service-card:hover {
    transform: translateY(-8px);
    border-color: var(--card-hover-border);
}

/* Hover glow gradient background */
.service-glow-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity var(--transition-speed);
    pointer-events: none;
    z-index: 1;
}

.glow-1 { background: radial-gradient(circle at 10% 10%, rgba(99, 102, 241, 0.12), transparent 60%); }
.glow-2 { background: radial-gradient(circle at 10% 10%, rgba(59, 130, 246, 0.12), transparent 60%); }
.glow-3 { background: radial-gradient(circle at 10% 10%, rgba(168, 85, 247, 0.12), transparent 60%); }
.glow-4 { background: radial-gradient(circle at 10% 10%, rgba(16, 185, 129, 0.12), transparent 60%); }
.glow-5 { background: radial-gradient(circle at 10% 10%, rgba(245, 158, 11, 0.12), transparent 60%); }

.service-card:hover .service-glow-bg {
    opacity: 1;
}

.service-card-content {
    position: relative;
    padding: 2.2rem;
    z-index: 2;
    display: flex;
    flex-direction: column;
    height: 100%;
    min-height: 280px;
}

.service-icon-box {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background-color: var(--card-border);
    color: var(--accent-color);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.service-card:hover .service-icon-box {
    background-color: var(--accent-color);
    color: #ffffff;
}

.service-title {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--card-title-color);
    margin-bottom: 0.8rem;
}

.service-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    flex-grow: 1;
}

.service-link-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--accent-color);
    font-weight: 600;
    font-size: 0.95rem;
    transition: color 0.2s;
    width: fit-content;
}

.service-link-btn .arrow {
    width: 16px;
    height: 16px;
    transition: transform 0.2s;
}

.service-card:hover .service-link-btn {
    color: var(--accent-hover);
}

.service-card:hover .service-link-btn .arrow {
    transform: translateX(4px);
}

/* --- Footer --- */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--card-border);
    padding: 4rem 0 3rem;
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.footer-logo i {
    color: var(--accent-color);
}

.footer-tagline {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.footer-right {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.5rem;
}

.server-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background-color: var(--card-border);
    padding: 0.3rem 0.8rem;
    border-radius: 100px;
    font-size: 0.8rem;
    color: var(--text-secondary);
    border: 1px solid var(--card-border);
}

.status-dot {
    width: 8px;
    height: 8px;
    background-color: #10b981;
    border-radius: 50%;
    display: inline-block;
    box-shadow: 0 0 8px #10b981;
    animation: blink 2s infinite;
}

.copyright {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* --- Animations --- */
@keyframes pulse {
    0% { transform: scale(1); box-shadow: 0 0 0 0 rgba(99, 102, 241, 0.4); }
    70% { transform: scale(1.02); box-shadow: 0 0 0 8px rgba(99, 102, 241, 0); }
    100% { transform: scale(1); box-shadow: 0 0 0 0 rgba(99, 102, 241, 0); }
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

/* --- Responsive Media Queries --- */
@media (max-width: 992px) {
    .hero-title {
        font-size: 3.5rem;
    }
}

@media (max-width: 768px) {
    .nav-container {
        padding: 0 1.5rem;
    }
    .nav-links {
        display: none; /* Hide standard links on mobile */
    }
    
    .hero-section {
        padding: 7rem 1.5rem 3rem;
    }
    
    .hero-title {
        font-size: 2.8rem;
    }
    
    .hero-subtitle {
        font-size: 1.05rem;
        margin-bottom: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .footer-container {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    .footer-right {
        align-items: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2.2rem;
    }
    .hero-actions {
        flex-direction: column;
        gap: 0.8rem;
    }
    .btn {
        width: 100%;
        justify-content: center;
    }
    .dashboard-grid, .services-grid {
        grid-template-columns: 1fr;
    }
}