/* ==========================================================================
   Tech Blend Tanning - Modern 2026 CSS Design System
   ========================================================================== */

/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ==========================================================================
   1. CSS Custom Properties - Design Tokens
   ========================================================================== */

:root {
    /* Light mode (default) */
    --bg: #f8fafc;
    --bg-elevated: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.7);
    --fg: #0f172a;
    --fg-muted: #64748b;
    --border-glass: rgba(255, 255, 255, 0.2);
    --border-subtle: rgba(15, 23, 42, 0.08);

    /* Accent colors */
    --accent: #f97316;
    --accent-light: #fb923c;
    --accent-dark: #ea580c;
    --accent-secondary: #06b6d4;
    --glow-orange: rgba(249, 115, 22, 0.4);
    --glow-cyan: rgba(6, 182, 212, 0.3);

    /* Semantic colors */
    --success: #22c55e;
    --warning: #eab308;
    --error: #ef4444;

    /* Spacing scale */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;

    /* Border radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    --shadow-glow: 0 0 40px var(--glow-orange);

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

    /* Typography */
    --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
}

/* ==========================================================================
   2. Dark Mode System
   ========================================================================== */

[data-theme="dark"] {
    --bg: #0a0a0f;
    --bg-elevated: #12121a;
    --bg-glass: rgba(255, 255, 255, 0.05);
    --fg: #ffffff;
    --fg-muted: #a1a1aa;
    --border-glass: rgba(255, 255, 255, 0.1);
    --border-subtle: rgba(255, 255, 255, 0.06);

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -4px rgba(0, 0, 0, 0.4);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.6), 0 8px 10px -6px rgba(0, 0, 0, 0.5);
}


@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: #0a0a0f;
        --bg-elevated: #12121a;
        --bg-glass: rgba(255, 255, 255, 0.05);
        --fg: #ffffff;
        --fg-muted: #a1a1aa;
        --border-glass: rgba(255, 255, 255, 0.1);
        --border-subtle: rgba(255, 255, 255, 0.06);

        --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
        --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
        --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -4px rgba(0, 0, 0, 0.4);
        --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.6), 0 8px 10px -6px rgba(0, 0, 0, 0.5);
    }
}

/* ==========================================================================
   3. Base Reset & Typography
   ========================================================================== */

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--fg);
    background-color: var(--bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Prevent flash of unstyled content */
html {
    visibility: visible;
    opacity: 1;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }

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

a:hover {
    color: var(--accent-light);
}

/* ==========================================================================
   4. Container & Layout
   ========================================================================== */

.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

main {
    flex: 1;
    padding: var(--space-2xl) 0;
    position: relative;
}

/* ==========================================================================
   5. Glassmorphism Components
   ========================================================================== */

.glass-card {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.glass-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.glass-nav {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-glass);
    box-shadow: var(--shadow-md);
}

.glass-input {
    background: var(--bg-glass);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    font-size: var(--font-size-base);
    color: var(--fg);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.glass-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--glow-orange);
}

/* Date input with custom calendar icon */
input[type="date"].glass-input {
    position: relative;
    padding-right: 40px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Crect x='3' y='4' width='18' height='18' rx='2' ry='2'%3E%3C/rect%3E%3Cline x1='16' y1='2' x2='16' y2='6'%3E%3C/line%3E%3Cline x1='8' y1='2' x2='8' y2='6'%3E%3C/line%3E%3Cline x1='3' y1='10' x2='21' y2='10'%3E%3C/line%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 20px;
}

input[type="date"].glass-input::-webkit-calendar-picker-indicator {
    opacity: 0;
    width: 40px;
    height: 100%;
    position: absolute;
    right: 0;
    cursor: pointer;
}

[data-theme="dark"] input[type="date"].glass-input {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%23a1a1aa' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Crect x='3' y='4' width='18' height='18' rx='2' ry='2'%3E%3C/rect%3E%3Cline x1='16' y1='2' x2='16' y2='6'%3E%3C/line%3E%3Cline x1='8' y1='2' x2='8' y2='6'%3E%3C/line%3E%3Cline x1='3' y1='10' x2='21' y2='10'%3E%3C/line%3E%3C/svg%3E");
}

/* ==========================================================================
   6. 3D Utility Classes
   ========================================================================== */

.perspective-container {
    perspective: 2000px;
    transform-style: preserve-3d;
}

.card-tilt {
    transform-style: preserve-3d;
    transition: transform var(--transition-base);
}

.card-tilt:hover {
    transform: rotateX(2deg) rotateY(-2deg) translateZ(10px);
}

.float-animation {
    animation: float 6s ease-in-out infinite;
}

.depth-1 { transform: translateZ(10px); }
.depth-2 { transform: translateZ(20px); }
.depth-3 { transform: translateZ(40px); }

/* ==========================================================================
   7. Buttons
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-lg);
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.2) 0%, transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.btn:hover::before {
    opacity: 1;
}

.btn:active {
    transform: translateY(2px) scale(0.98);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    color: white;
    box-shadow: 0 4px 14px var(--glow-orange);
}

.btn-primary:hover {
    box-shadow: 0 6px 20px var(--glow-orange);
    transform: translateY(-2px);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--accent-secondary) 0%, #0891b2 100%);
    color: white;
    box-shadow: 0 4px 14px var(--glow-cyan);
}

.btn-secondary:hover {
    box-shadow: 0 6px 20px var(--glow-cyan);
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--accent);
    color: var(--accent);
}

.btn-outline:hover {
    background: var(--accent);
    color: white;
}

.btn-ghost {
    background: var(--bg-glass);
    backdrop-filter: blur(10px);
    color: var(--fg);
    border: 1px solid var(--border-glass);
}

.btn-ghost:hover {
    background: var(--border-glass);
}

.btn-small {
    padding: var(--space-xs) var(--space-md);
    font-size: var(--font-size-xs);
    border-radius: var(--radius-sm);
}

.btn-large {
    padding: var(--space-md) var(--space-xl);
    font-size: var(--font-size-base);
    border-radius: var(--radius-lg);
}

.btn-inline {
    width: auto;
}

/* ==========================================================================
   8. Navigation
   ========================================================================== */

header {
    position: fixed;
    top: var(--space-md);
    left: 50%;
    transform: translateX(-50%);
    width: calc(100% - var(--space-xl));
    max-width: 1200px;
    z-index: 1000;
    border-radius: var(--radius-xl);
    padding: var(--space-sm) var(--space-lg);
}

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

.logo {
    font-size: var(--font-size-xl);
    font-weight: 800;
    color: var(--fg);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    flex-shrink: 0;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--space-xs);
    align-items: center;
}

.nav-links a {
    color: var(--fg);
    text-decoration: none;
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-md);
    font-weight: 500;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.nav-links a:hover {
    background: var(--bg-glass);
    color: var(--accent);
}

.nav-links a.active {
    background: var(--accent);
    color: white;
}

/* Theme Toggle Button */
.theme-toggle {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    color: var(--fg);
    flex-shrink: 0;
}

.theme-toggle:hover {
    background: var(--accent);
    color: white;
    transform: rotate(180deg);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    color: var(--fg);
    flex-shrink: 0;
}

.menu-toggle:hover {
    background: var(--accent);
    color: white;
}

.menu-toggle svg {
    width: 18px;
    height: 18px;
}

/* ==========================================================================
   9. Hero Section
   ========================================================================== */

.hero {
    position: relative;
    min-height: 60vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: var(--space-3xl) var(--space-lg);
    margin-top: 80px;
    overflow: hidden;
    background: radial-gradient(ellipse at 50% 0%, var(--glow-orange) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 50%, var(--glow-cyan) 0%, transparent 40%),
                radial-gradient(ellipse at 20% 80%, var(--glow-orange) 0%, transparent 40%);
}

.hero h1 {
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    font-weight: 800;
    margin-bottom: var(--space-lg);
    letter-spacing: -0.03em;
}

.hero p {
    font-size: var(--font-size-lg);
    color: var(--fg-muted);
    max-width: 600px;
    margin-bottom: var(--space-xl);
}

.hero .btn-group,
.hero-actions {
    display: flex;
    gap: var(--space-md);
    flex-wrap: wrap;
    justify-content: center;
}

.hero-actions .btn {
    min-width: 160px;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-float {
    position: absolute;
    bottom: 10%;
    right: 10%;
    opacity: 0.15;
    animation: float 6s ease-in-out infinite;
}

.float-icon {
    width: 120px;
    height: 120px;
    color: var(--accent);
}

/* Section Titles */
.section-title {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--space-lg);
    text-align: center;
}

/* Quick Actions Section */
.quick-actions,
.features {
    padding: var(--space-2xl) 0;
}

/* Animated Orbs */
.orb {
    position: absolute;
    border-radius: var(--radius-full);
    filter: blur(80px);
    pointer-events: none;
    z-index: -1;
}

.orb-1 {
    width: 400px;
    height: 400px;
    background: var(--accent);
    opacity: 0.3;
    top: -100px;
    right: -100px;
    animation: orb-float 8s ease-in-out infinite;
}

.orb-2 {
    width: 300px;
    height: 300px;
    background: var(--accent-secondary);
    opacity: 0.25;
    bottom: -50px;
    left: -50px;
    animation: orb-float 10s ease-in-out infinite reverse;
}

.orb-3 {
    width: 200px;
    height: 200px;
    background: var(--accent-light);
    opacity: 0.2;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation: orb-float 12s ease-in-out infinite;
}

/* ==========================================================================
   10. Cards
   ========================================================================== */

.card {
    background: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: all var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-lg);
}

/* Action Cards */
.action-grid {
    display: grid;
    gap: var(--space-lg);
    margin-top: var(--space-xl);
}

.action-card {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
    padding: var(--space-lg);
    text-decoration: none;
    color: var(--fg);
    transition: all var(--transition-base);
    transform-style: preserve-3d;
}

.action-card:hover {
    transform: translateY(-8px) rotateX(2deg);
    box-shadow: 0 20px 40px -15px var(--glow-orange);
}

.action-card .icon-wrapper,
.card-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.card-icon svg,
.card-icon [data-lucide] {
    width: 24px;
    height: 24px;
}

.action-card h3 {
    font-size: var(--font-size-lg);
    color: var(--fg);
    margin-top: var(--space-sm);
}

.action-card p {
    color: var(--fg-muted);
    font-size: var(--font-size-sm);
    margin-top: var(--space-xs);
}

/* Session Cards */
.sessions-grid {
    display: grid;
    gap: var(--space-lg);
    margin-top: var(--space-lg);
}

.session-card {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    padding: var(--space-lg);
}

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

.session-date {
    font-weight: 600;
    font-size: var(--font-size-base);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.session-duration {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    color: white;
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--radius-full);
    font-size: var(--font-size-sm);
    font-weight: 600;
}

.session-notes {
    color: var(--fg-muted);
    font-size: var(--font-size-sm);
    line-height: 1.5;
}

.session-actions {
    margin-top: auto;
    padding-top: var(--space-md);
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

.session-actions .btn {
    width: auto;
}

/* User Cards */
.users-grid {
    display: grid;
    gap: var(--space-lg);
    margin-top: var(--space-lg);
}

.user-card {
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.user-card h3 {
    margin-bottom: 0;
}

.user-email {
    color: var(--fg-muted);
    font-size: var(--font-size-sm);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.user-joined {
    font-size: var(--font-size-xs);
    color: var(--fg-muted);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.user-actions {
    display: flex;
    gap: var(--space-sm);
    margin-top: auto;
    padding-top: var(--space-md);
    flex-wrap: wrap;
}

.user-actions .btn {
    width: auto;
}

/* Feature Grid */
.feature-grid {
    display: grid;
    gap: var(--space-lg);
    margin-top: var(--space-lg);
}

.feature-card {
    padding: var(--space-lg);
    text-align: center;
}

.feature-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto var(--space-md);
    border-radius: var(--radius-lg);
    background: linear-gradient(135deg, var(--accent-secondary) 0%, #0891b2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.feature-icon svg,
.feature-icon [data-lucide] {
    width: 28px;
    height: 28px;
}

.feature-card h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--space-sm);
}

.feature-card p {
    color: var(--fg-muted);
    font-size: var(--font-size-sm);
}

/* ==========================================================================
   11. Forms
   ========================================================================== */

.form-section {
    margin-bottom: var(--space-2xl);
    padding: var(--space-xl);
}

.form-section.glass-card {
    margin-top: var(--space-lg);
}

.form-group {
    margin-bottom: var(--space-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--space-sm);
    font-weight: 500;
    color: var(--fg);
    font-size: var(--font-size-sm);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--space-md);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-family: var(--font-sans);
    background: var(--bg-elevated);
    color: var(--fg);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 4px var(--glow-orange);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--fg-muted);
}

.form-group textarea {
    min-height: 80px;
    resize: vertical;
}

/* Form Enhancements */
.form-title {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: var(--font-size-xl);
    margin-bottom: var(--space-lg);
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-md);
}

.modern-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.modern-form .form-group {
    margin-bottom: 0;
}

.btn-block {
    width: 100%;
}

.btn-danger {
    background: linear-gradient(135deg, var(--error) 0%, #dc2626 100%);
    color: white;
}

.btn-danger:hover {
    box-shadow: 0 6px 20px rgba(239, 68, 68, 0.4);
    transform: translateY(-2px);
}

/* ==========================================================================
   12. Page Header
   ========================================================================== */

.page-header {
    margin-bottom: var(--space-2xl);
    margin-top: 100px;
}

.page-header h1 {
    margin-bottom: var(--space-sm);
}

.page-header p {
    color: var(--fg-muted);
    font-size: var(--font-size-lg);
}

.page-title {
    font-size: var(--font-size-4xl);
}

.page-subtitle {
    color: var(--fg-muted);
    font-size: var(--font-size-lg);
    margin-top: var(--space-sm);
}

/* Section Spacing */
.sessions-section,
.users-section {
    margin-top: var(--space-2xl);
    padding-bottom: var(--space-xl);
}

.sessions-section .section-title,
.users-section .section-title {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

/* User Card Enhancements */
.user-avatar {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    margin-bottom: var(--space-md);
}

.user-avatar svg,
.user-avatar [data-lucide] {
    width: 24px;
    height: 24px;
}

.user-info {
    flex: 1;
}

.user-name {
    font-size: var(--font-size-lg);
    margin-bottom: var(--space-xs);
}

/* Empty State Icon */
.empty-icon {
    margin-bottom: var(--space-md);
    opacity: 0.5;
}

.empty-icon svg,
.empty-icon [data-lucide] {
    width: 48px;
    height: 48px;
}

/* ==========================================================================
   13. Empty State
   ========================================================================== */

.empty-state {
    text-align: center;
    padding: var(--space-3xl);
    color: var(--fg-muted);
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-glass);
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: var(--space-lg);
    opacity: 0.5;
}

.empty-state h3 {
    margin-bottom: var(--space-sm);
    color: var(--fg);
}

/* ==========================================================================
   14. Footer
   ========================================================================== */

footer {
    background: var(--bg-elevated);
    border-top: 1px solid var(--border-subtle);
    padding: var(--space-xl) 0;
    margin-top: auto;
    text-align: center;
    color: var(--fg-muted);
}

footer a {
    color: var(--accent);
}

footer a:hover {
    color: var(--accent-light);
}

/* ==========================================================================
   15. Lucide Icons
   ========================================================================== */

[data-lucide] {
    width: 1.25em;
    height: 1.25em;
    vertical-align: middle;
    display: inline-block;
}

.logo [data-lucide] {
    width: 1.5em;
    height: 1.5em;
}

.nav-links [data-lucide] {
    margin-right: var(--space-xs);
}

.btn [data-lucide] {
    margin-right: var(--space-sm);
}

.icon-lg {
    width: 2em;
    height: 2em;
}

.icon-sm {
    width: 1em;
    height: 1em;
}

/* ==========================================================================
   16. Keyframe Animations
   ========================================================================== */

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes glow-pulse {
    0%, 100% {
        box-shadow: 0 0 20px var(--glow-orange);
    }
    50% {
        box-shadow: 0 0 40px var(--glow-orange), 0 0 60px var(--glow-orange);
    }
}

@keyframes gradient-shift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

@keyframes fade-in-up {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes orb-float {
    0%, 100% {
        transform: translate(0, 0) scale(1);
    }
    25% {
        transform: translate(30px, -30px) scale(1.1);
    }
    50% {
        transform: translate(0, -50px) scale(1);
    }
    75% {
        transform: translate(-30px, -30px) scale(0.9);
    }
}

@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* ==========================================================================
   17. Utility Classes
   ========================================================================== */

.gradient-text {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-secondary) 50%, var(--accent-light) 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 4s ease infinite;
}

.glow {
    box-shadow: 0 0 30px var(--glow-orange);
}

.glow-cyan {
    box-shadow: 0 0 30px var(--glow-cyan);
}

.glow-pulse {
    animation: glow-pulse 2s ease-in-out infinite;
}

.fade-in {
    animation: fade-in-up 0.6s ease-out forwards;
}

.fade-in-delay-1 { animation-delay: 0.1s; opacity: 0; }
.fade-in-delay-2 { animation-delay: 0.2s; opacity: 0; }
.fade-in-delay-3 { animation-delay: 0.3s; opacity: 0; }
.fade-in-delay-4 { animation-delay: 0.4s; opacity: 0; }

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

.text-muted { color: var(--fg-muted); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-error { color: var(--error); }

.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.flex-col { flex-direction: column; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

.p-sm { padding: var(--space-sm); }
.p-md { padding: var(--space-md); }
.p-lg { padding: var(--space-lg); }
.p-xl { padding: var(--space-xl); }

.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* ==========================================================================
   18. Responsive Design
   ========================================================================== */

/* Tablet and up */
@media (min-width: 600px) {
    .action-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .sessions-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .users-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .hero h1 {
        font-size: var(--font-size-5xl);
    }
}

/* Desktop */
@media (min-width: 900px) {
    .action-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .feature-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .sessions-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .users-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Mobile */
@media (max-width: 599px) {
    header {
        top: var(--space-sm);
        left: var(--space-sm);
        right: var(--space-sm);
        transform: none;
        width: calc(100% - var(--space-md));
        border-radius: var(--radius-lg);
        padding: var(--space-sm) var(--space-md);
    }

    .logo span {
        display: none;
    }

    .logo::after {
        content: 'TBT';
        font-size: var(--font-size-lg);
        font-weight: 800;
    }

    /* Form mobile adjustments */
    .form-section {
        padding: var(--space-md);
    }

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

    .form-title {
        font-size: var(--font-size-lg);
    }

    .glass-input {
        padding: var(--space-sm);
        font-size: var(--font-size-sm);
    }

    /* Date input mobile fixes */
    input[type="date"].glass-input {
        width: 100%;
        min-height: 44px;
        -webkit-appearance: none;
        appearance: none;
        line-height: 1.5;
    }

    input[type="date"].glass-input::-webkit-date-and-time-value {
        text-align: left;
    }

    input[type="date"].glass-input::-webkit-calendar-picker-indicator {
        opacity: 0.7;
        cursor: pointer;
    }

    .page-title {
        font-size: var(--font-size-2xl);
    }

    .page-subtitle {
        font-size: var(--font-size-sm);
    }

    .section-title {
        font-size: var(--font-size-lg);
    }

    .nav-actions {
        gap: var(--space-sm);
    }

    .menu-toggle {
        display: flex;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: calc(100% + var(--space-sm));
        left: 0;
        right: 0;
        background: var(--bg-elevated);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        flex-direction: column;
        padding: var(--space-sm);
        gap: var(--space-xs);
        border: 1px solid var(--border-glass);
        border-radius: var(--radius-lg);
        box-shadow: var(--shadow-xl);
    }

    .nav-links.active {
        display: flex;
        animation: slideDown 0.2s ease-out;
    }

    @keyframes slideDown {
        from {
            opacity: 0;
            transform: translateY(-10px);
        }
        to {
            opacity: 1;
            transform: translateY(0);
        }
    }

    .nav-links li {
        border-bottom: none;
    }

    .nav-links a {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        padding: var(--space-md);
        width: 100%;
        border-radius: var(--radius-md);
        transition: background var(--transition-fast);
    }

    .nav-links a:hover {
        background: var(--bg-glass);
    }

    .hero {
        min-height: 50vh;
        padding: var(--space-2xl) var(--space-md);
        margin-top: 60px;
    }

    .hero h1 {
        font-size: var(--font-size-3xl);
    }

    .hero .btn-group,
    .hero-actions {
        flex-direction: column;
        width: 100%;
    }

    .hero .btn-group .btn,
    .hero-actions .btn {
        width: 100%;
        min-width: unset;
    }

    .hero-float {
        display: none;
    }

    .page-header {
        margin-top: 80px;
    }

    .orb-1 {
        width: 200px;
        height: 200px;
    }

    .orb-2 {
        width: 150px;
        height: 150px;
    }

    .orb-3 {
        width: 100px;
        height: 100px;
    }
}

/* ==========================================================================
   19. Reduced Motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .float-animation,
    .orb,
    .glow-pulse {
        animation: none;
    }

    .card-tilt:hover,
    .action-card:hover {
        transform: none;
    }
}

/* ==========================================================================
   20. Print Styles
   ========================================================================== */

@media print {
    header,
    footer,
    .orb,
    .theme-toggle,
    .menu-toggle {
        display: none !important;
    }

    body {
        background: white;
        color: black;
    }

    .card,
    .glass-card {
        border: 1px solid #ccc;
        box-shadow: none;
        backdrop-filter: none;
    }

    .hero {
        min-height: auto;
        padding: var(--space-xl);
        background: none;
    }

    .gradient-text {
        -webkit-text-fill-color: var(--accent);
        background: none;
    }
}