:root {
    --primary: #8B5CF6;
    --primary-glow: rgba(139, 92, 246, 0.6);
    --success: #10B981;
    --success-glow: rgba(16, 185, 129, 0.6);
    --warning: #F59E0B;
    --warning-glow: rgba(245, 158, 11, 0.6);
    --error: #EF4444;
    --error-glow: rgba(239, 68, 68, 0.6);
    
    --bg-grad-1: #2a2a36;
    --bg-grad-2: #1e1e26;
    
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --text-main: #F3F4F6;
    --text-muted: #9CA3AF;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
    background: radial-gradient(circle at top left, var(--bg-grad-1), var(--bg-grad-2));
    color: var(--text-main);
    padding: 20px 15px;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    position: relative;
    overflow-x: hidden;
}

.noise-overlay {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    pointer-events: none;
    z-index: -1;
    opacity: 0.4;
    background: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

.container {
    width: 100%;
    max-width: 600px;
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 32px 24px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    height: fit-content;
}

header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-bottom: 32px;
}

.logo {
    width: 45px;
    height: 45px;
    object-fit: contain;
    border-radius: 8px;
    box-shadow: 0 0 15px var(--primary-glow);
}

.header-text h1 {
    font-size: 1.8rem;
    background: linear-gradient(to right, #C4B5FD, #8B5CF6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.header-text p {
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.input-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 32px;
}

input {
    width: 100%;
    max-width: 320px;
    font-size: 2.2rem;
    text-align: center;
    text-transform: uppercase;
    padding: 16px;
    background: rgba(0, 0, 0, 0.2);
    color: #FFFFFF;
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    outline: none;
    transition: all 0.3s ease;
    letter-spacing: 6px;
    font-weight: 800;
}

input::placeholder {
    color: rgba(255, 255, 255, 0.2);
    letter-spacing: 2px;
    font-weight: 500;
}

input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 20px var(--primary-glow);
}

.status-message {
    margin-top: 20px;
    font-size: 1.1rem;
    font-weight: 700;
    padding: 12px 20px;
    border-radius: 10px;
    width: 100%;
    max-width: 320px;
    text-align: center;
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-muted);
    border: 1px solid var(--glass-border);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.status-message.valid {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border-color: var(--success);
    box-shadow: 0 0 20px var(--success-glow);
}

.status-message.used {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning);
    border-color: var(--warning);
    box-shadow: 0 0 20px var(--warning-glow);
}

.status-message.invalid {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border-color: var(--error);
    box-shadow: 0 0 20px var(--error-glow);
}

/* Action Buttons */
.redeem-btn, .undo-btn {
    margin-top: 16px;
    padding: 12px 24px;
    width: 100%;
    max-width: 320px;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 800;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 2px;
    transition: all 0.3s ease;
}

.redeem-btn {
    background: var(--primary);
    color: white;
    border: none;
    box-shadow: 0 4px 15px var(--primary-glow);
}

.redeem-btn:hover {
    background: #7C3AED;
    transform: translateY(-2px);
}

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

.undo-btn:hover {
    background: rgba(245, 158, 11, 0.15);
    box-shadow: 0 4px 15px var(--warning-glow);
    transform: translateY(-2px);
}

.redeem-btn.hidden, .undo-btn.hidden {
    display: none;
}

.list-section h2 {
    font-size: 1rem;
    margin-bottom: 20px;
    text-align: center;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 2px;
}

.code-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
    gap: 12px;
}

.code-item {
    background-color: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    padding: 12px 8px;
    text-align: center;
    font-weight: 600;
    font-family: 'Courier New', Courier, monospace;
    font-size: 1.1rem;
    color: #6B7280;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.code-item.is-used {
    text-decoration: line-through;
    opacity: 0.4;
    border-color: var(--warning);
    color: var(--warning);
}

@keyframes pulseGlow {
    0% { box-shadow: 0 0 10px var(--success-glow); }
    50% { box-shadow: 0 0 25px var(--success-glow); }
    100% { box-shadow: 0 0 10px var(--success-glow); }
}

@keyframes pulseWarning {
    0% { box-shadow: 0 0 10px var(--warning-glow); }
    50% { box-shadow: 0 0 25px var(--warning-glow); }
    100% { box-shadow: 0 0 10px var(--warning-glow); }
}

.code-item.highlight-valid {
    background-color: var(--success);
    color: #000000;
    border-color: var(--success);
    transform: scale(1.15);
    z-index: 10;
    position: relative;
    font-weight: 800;
    animation: pulseGlow 1.5s infinite;
}

.code-item.highlight-used {
    background-color: transparent;
    color: var(--warning);
    border-color: var(--warning);
    transform: scale(1.15);
    z-index: 10;
    position: relative;
    font-weight: 800;
    opacity: 1; 
    animation: pulseWarning 1.5s infinite;
}