:root {
    /* Moderne Farbpalette */
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --accent: #ec4899;
    --accent-dark: #db2777;
    
    /* Backgrounds */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    
    /* Glass Effect */
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(148, 163, 184, 0.1);
    
    /* Text */
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    
    /* Status Colors */
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.3);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
}

/* Animated Background */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(236, 72, 153, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 40% 20%, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
    animation: gradientShift 15s ease infinite;
    pointer-events: none;
    z-index: 0;
}

@keyframes gradientShift {
    0%, 100% { transform: scale(1) rotate(0deg); opacity: 1; }
    50% { transform: scale(1.1) rotate(5deg); opacity: 0.8; }
}

/* Container */
.container {
    width: 100%;
    max-width: 500px;
    margin: 0 auto;
    padding: 40px 20px;
    position: relative;
    z-index: 1;
    animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Panel */
.panel {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    animation: scaleIn 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.panel:hover {
    border-color: rgba(148, 163, 184, 0.2);
    box-shadow: var(--shadow-xl), var(--shadow-glow);
    transform: translateY(-2px);
}

/* Panel Header */
.panel-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    padding: 40px 30px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.panel-header::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: headerShine 3s ease-in-out infinite;
}

@keyframes headerShine {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(10%, 10%); }
}

.panel-header h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 8px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    position: relative;
    z-index: 1;
    letter-spacing: -0.5px;
}

.subtitle {
    color: rgba(255, 255, 255, 0.95);
    font-size: 16px;
    font-weight: 500;
    position: relative;
    z-index: 1;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

/* User Info in Header */
.user-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    z-index: 1;
}

.user-info span {
    font-weight: 600;
    font-size: 15px;
    display: flex;
    align-items: center;
    gap: 6px;
}

/* Panel Body */
.panel-body {
    padding: 40px 30px;
}

/* Form Groups */
.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 10px;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 0.3px;
    text-transform: uppercase;
}

.form-group input {
    width: 100%;
    padding: 14px 18px;
    background: rgba(15, 23, 42, 0.5);
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 15px;
    font-family: inherit;
    transition: all 0.3s ease;
    outline: none;
}

.form-group input:focus {
    border-color: var(--primary);
    background: rgba(15, 23, 42, 0.7);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1), 0 0 20px rgba(99, 102, 241, 0.2);
    transform: translateY(-1px);
}

.form-group input::placeholder {
    color: var(--text-muted);
}

/* Buttons */
.btn {
    width: 100%;
    padding: 14px 24px;
    border: none;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    margin-bottom: 12px;
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
    position: relative;
    z-index: 1;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(99, 102, 241, 0.5);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border: 2px solid var(--glass-border);
}

.btn-secondary:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-color: var(--text-muted);
    transform: translateY(-2px);
}

.btn-small {
    width: auto;
    padding: 10px 20px;
    font-size: 13px;
    margin: 0;
}

/* Messages */
.error-message,
.success-message {
    font-size: 14px;
    margin: 20px 0;
    padding: 14px 18px;
    border-radius: 12px;
    border-left: 4px solid;
    display: none;
    animation: slideInRight 0.3s ease-out;
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.error-message {
    color: var(--error);
    background: rgba(239, 68, 68, 0.1);
    border-left-color: var(--error);
}

.success-message {
    color: var(--success);
    background: rgba(16, 185, 129, 0.1);
    border-left-color: var(--success);
}

.error-message.show,
.success-message.show {
    display: block;
}

.hidden {
    display: none !important;
}

.info-text {
    color: var(--text-muted);
    font-size: 14px;
    margin-top: 20px;
    text-align: center;
    font-style: italic;
}

h2 {
    color: var(--primary-light);
    margin-bottom: 16px;
    font-size: 24px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Loading Spinner */
.btn.loading {
    position: relative;
    color: transparent;
    pointer-events: none;
}

.btn.loading::after {
    content: "";
    position: absolute;
    width: 18px;
    height: 18px;
    top: 50%;
    left: 50%;
    margin-left: -9px;
    margin-top: -9px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Hover Effects für Inputs */
.form-group input:hover {
    border-color: rgba(148, 163, 184, 0.3);
}

/* Focus Within Effect für Form Group */
.form-group:focus-within label {
    color: var(--primary-light);
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}

/* Responsive Design */
@media (max-width: 640px) {
    .container {
        padding: 20px 15px;
    }
    
    .panel-header {
        padding: 30px 20px;
    }
    
    .panel-header h1 {
        font-size: 28px;
    }
    
    .panel-body {
        padding: 30px 20px;
    }
    
    .form-group input {
        padding: 12px 16px;
    }
    
    .btn {
        padding: 12px 20px;
    }
}

/* Accessibility */
.btn:focus-visible,
.form-group input:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Pulse Animation für wichtige Elemente */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.8;
    }
}

/* Glow Effect für Buttons */
.btn-primary:hover {
    animation: buttonGlow 1.5s ease-in-out infinite;
}

@keyframes buttonGlow {
    0%, 100% {
        box-shadow: 0 6px 25px rgba(99, 102, 241, 0.5);
    }
    50% {
        box-shadow: 0 6px 35px rgba(99, 102, 241, 0.7);
    }
}

/* Smooth transitions for all interactive elements */
a, button, input, select, textarea {
    transition: all 0.3s ease;
}

/* Selection styling */
::selection {
    background-color: var(--primary);
    color: white;
}

::-moz-selection {
    background-color: var(--primary);
    color: white;
}

/* Link styling (falls benötigt) */
a {
    color: var(--primary-light);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

/* Toggle Checkbox & Optional Fields */
.toggle-checkbox {
    display: flex;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    user-select: none;
    padding: 12px;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.toggle-checkbox:hover {
    background: var(--bg-secondary);
}

.toggle-checkbox input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary);
}

.toggle-checkbox.active {
    background: rgba(99, 102, 241, 0.1);
    border-left: 3px solid var(--primary);
}

.optional-field {
    display: none;
    opacity: 0;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease;
}

.optional-field.active {
    display: flex;
    opacity: 1;
    max-height: 200px;
}