/* Design Tokens & Theme Colors */
:root {
    --color-primary: hsl(244, 75%, 60%);
    --color-primary-glow: hsl(244, 75%, 60%, 0.15);
    --color-bg: #09090b;
    --color-card: #121214;
    --color-border: rgba(255, 255, 255, 0.08);
    --color-text: #f4f4f5;
    --color-text-muted: #a1a1aa;
    --color-header-bg: rgba(15, 17, 21, 0.85);
    --color-input-bg: rgba(255, 255, 255, 0.05);
    --color-input-bg-focus: rgba(255, 255, 255, 0.08);
    --color-feature-card-bg: rgba(18, 18, 20, 0.7);
    --color-feature-card-border: rgba(255, 255, 255, 0.06);
    --color-grid-line: rgba(255, 255, 255, 0.02);
    --color-dashboard-bg: radial-gradient(circle at 10% 20%, #17182f 0%, #0c0d19 90%);
    --color-dashboard-sidebar-bg: rgba(12, 13, 25, 0.7);
    
    --color-vcc: #ef4444;
    --color-gnd: #18181b;
    --color-digital: #eab308;
    --color-analog: #3b82f6;
    --color-i2c: #a855f7;

    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;
    --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light Theme Variables */
[data-theme="light"] {
    --color-primary: hsl(244, 75%, 55%);
    --color-primary-glow: hsl(244, 75%, 55%, 0.1);
    --color-bg: #fafafa;
    --color-card: #ffffff;
    --color-border: rgba(0, 0, 0, 0.08);
    --color-text: #09090b;
    --color-text-muted: #71717a;
    --color-header-bg: rgba(255, 255, 255, 0.85);
    --color-input-bg: rgba(0, 0, 0, 0.04);
    --color-input-bg-focus: rgba(0, 0, 0, 0.06);
    --color-feature-card-bg: rgba(255, 255, 255, 0.75);
    --color-feature-card-border: rgba(0, 0, 0, 0.06);
    --color-grid-line: rgba(0, 0, 0, 0.04);
    --color-dashboard-bg: radial-gradient(circle at 10% 20%, #f3f4f6 0%, #e5e7eb 90%);
    --color-dashboard-sidebar-bg: rgba(255, 255, 255, 0.75);

    --color-vcc: #e11d48;
    --color-gnd: #27272a;
    --color-digital: #d97706;
    --color-analog: #2563eb;
    --color-i2c: #9333ea;

    --color-success: #059669;
    --color-warning: #d97706;
    --color-danger: #dc2626;
}

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

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

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    margin-bottom: 0.5em;
    color: var(--color-text);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--color-primary-hover);
}

/* Container & Grid layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Navbar styling */
header {
    background-color: var(--color-header-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 800;
    color: var(--color-text);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo span {
    background: linear-gradient(135deg, var(--color-primary), var(--color-success));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-links {
    display: flex;
    gap: 24px;
    list-style: none;
}

.nav-links a {
    color: var(--color-text-muted);
    font-weight: 500;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--color-text);
}

.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    border: none;
    transition: var(--transition);
}

.btn-primary {
    background-color: var(--color-primary);
    color: #fff;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 2px 4px rgba(0,0,0,0.2);
}

.btn-primary:hover {
    filter: brightness(1.1);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--color-primary-glow);
}

.btn-primary:active {
    transform: scale(0.97);
}

.btn-secondary {
    background-color: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
}

.btn-secondary:hover {
    background-color: var(--color-primary-glow);
    border-color: var(--color-primary);
    transform: translateY(-1px);
}

.btn-secondary:active {
    transform: scale(0.97);
}

/* Card & Panels */
.card {
    background-color: var(--color-card);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
    transition: var(--transition);
}

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

/* Hero Section */
.hero {
    padding: 100px 0 60px;
    text-align: center;
    position: relative;
}

.hero h1, .hero-title {
    font-size: 48px;
    line-height: 1.2;
    margin-bottom: 20px;
}

.hero p, .hero-desc {
    font-size: 18px;
    color: var(--color-text-muted);
    max-width: 650px;
    margin: 0 auto 30px;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
}

/* Features Grid */
.features {
    padding: 80px 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

/* Footer style */
footer {
    background-color: rgba(15, 17, 21, 0.95);
    border-top: 1px solid var(--color-border);
    padding: 40px 0;
    text-align: center;
    color: var(--color-text-muted);
    margin-top: 80px;
}

/* Error page layouts */
.error-container {
    max-width: 500px;
    margin: 100px auto;
    text-align: center;
    padding: 40px 20px;
}

.error-code {
    font-size: 120px;
    font-weight: 800;
    line-height: 1;
    background: linear-gradient(135deg, var(--color-danger), var(--color-warning));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}

.error-message {
    color: var(--color-text-muted);
    margin-bottom: 30px;
}

.error-details {
    background-color: hsl(220, 15%, 5%);
    color: var(--color-danger);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: 15px;
    text-align: left;
    overflow-x: auto;
    font-family: monospace;
    font-size: 13px;
    margin-bottom: 30px;
}

/* Theme Switcher */
.theme-switch {
    background: none;
    border: none;
    color: var(--color-text-muted);
    cursor: pointer;
    font-size: 20px;
    padding: 8px;
    border-radius: 50%;
    transition: var(--transition);
}

.theme-switch:hover {
    color: var(--color-text);
    background-color: var(--color-card);
}

/* Mobile Navigation Hamburger Toggle */
.mobile-nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--color-text);
    font-size: 22px;
    cursor: pointer;
    padding: 8px;
}

/* Mobile Responsive Breakpoints */
@media (max-width: 768px) {
    .mobile-nav-toggle {
        display: inline-flex !important;
        align-items: center;
        justify-content: center;
    }

    .navbar {
        height: 60px;
        position: relative;
    }

    /* Hide desktop header buttons on mobile topbar to avoid crowding */
    .nav-actions a.btn,
    .nav-actions .user-badge {
        display: none !important;
    }

    /* Show mobile auth drawer links */
    .mobile-auth-links {
        display: flex !important;
        flex-direction: column;
        gap: 10px;
        margin-top: 8px;
        padding-top: 16px;
        border-top: 1px solid var(--color-border);
    }

    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        background: var(--color-header-bg);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        border-bottom: 1px solid var(--color-border);
        padding: 20px 16px;
        gap: 16px;
        box-shadow: 0 16px 40px rgba(0, 0, 0, 0.6);
        z-index: 999;
    }

    .nav-links.show {
        display: flex !important;
    }

    .hero {
        padding: 50px 0 30px !important;
    }

    .hero h1 {
        font-size: 28px !important;
        line-height: 1.25 !important;
        margin-bottom: 16px !important;
    }

    .hero p {
        font-size: 14px !important;
        line-height: 1.5 !important;
        padding: 0 8px;
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
        gap: 10px !important;
    }

    .hero-actions .btn {
        width: 100% !important;
        justify-content: center;
        padding: 12px 16px !important;
        font-size: 14px !important;
    }

    .features {
        padding: 40px 0 20px !important;
    }

    .features h2 {
        font-size: 24px !important;
    }

    .features p {
        font-size: 14px !important;
    }

    .features-grid {
        grid-template-columns: 1fr !important;
        gap: 16px !important;
    }

    .feature-card {
        padding: 24px 20px !important;
    }

    .container {
        padding: 0 16px !important;
        width: 100% !important;
        max-width: 100% !important;
    }

    .landing-container {
        padding-bottom: 40px !important;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 19px;
    }
    
    .hero h1 {
        font-size: 24px !important;
    }
}