:root {
    --bg-color: #0f172a;
    --text-primary: #ffffff;
    --text-secondary: #94a3b8;
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-border: rgba(255, 255, 255, 0.1);
    --primary-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
    --secondary-gradient: linear-gradient(135deg, #ec4899 0%, #f43f5e 100%);
    --tertiary-gradient: linear-gradient(135deg, #10b981 0%, #0ea5e9 100%);
    --quaternary-gradient: linear-gradient(135deg, #f97316 0%, #eab308 100%);
    --quinary-gradient: linear-gradient(135deg, #22c55e 0%, #84cc16 100%);
    --senary-gradient: linear-gradient(135deg, #0ea5e9 0%, #6366f1 100%);
    --septenary-gradient: linear-gradient(135deg, #ef4444 0%, #f97316 100%);
    --octonary-gradient: linear-gradient(135deg, #8b5cf6 0%, #d946ef 100%);
    --nonary-gradient: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
    --denary-gradient: linear-gradient(135deg, #f43f5e 0%, #8b5cf6 100%);
    --undenary-gradient: linear-gradient(135deg, #14b8a6 0%, #0284c7 100%);
    --empty-gradient: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Outfit', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
    position: relative;
}

/* Background animated shapes for vibrant look */
.background-shapes {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: -1;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.6;
    animation: float 20s infinite alternate ease-in-out;
}

.shape-1 {
    width: 400px;
    height: 400px;
    background: #6366f1;
    top: -100px;
    left: -100px;
}

.shape-2 {
    width: 500px;
    height: 500px;
    background: #ec4899;
    bottom: -150px;
    right: -100px;
    animation-delay: -5s;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: #3b82f6;
    top: 40%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(50px, 30px) scale(1.1); }
    100% { transform: translate(-30px, 60px) scale(0.9); }
}

.container {
    width: 100%;
    max-width: 800px;
    padding: 2rem;
    z-index: 1;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    animation: slideDown 0.8s ease-out;
}

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

header h1 {
    font-size: 2rem;
    font-weight: 300;
    letter-spacing: 2px;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

header h2 {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(to right, #fff, #cbd5e1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1rem;
}

header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
    animation: fadeIn 1s ease-out 0.3s both;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.card {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    border-radius: 24px;
    text-decoration: none;
    color: var(--text-primary);
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    height: 160px;
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: inherit;
    z-index: -1;
    transition: opacity 0.4s;
    opacity: 0;
}

.card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    border-color: rgba(255, 255, 255, 0.3);
}

.btn-primary {
    background: var(--primary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 15px 30px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: var(--secondary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(236, 72, 153, 0.3);
}

.btn-secondary:hover {
    box-shadow: 0 15px 30px rgba(236, 72, 153, 0.5);
}

.btn-tertiary {
    background: var(--tertiary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(16, 185, 129, 0.3);
}

.btn-tertiary:hover {
    box-shadow: 0 15px 30px rgba(16, 185, 129, 0.5);
}

.btn-quaternary {
    background: var(--quaternary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(249, 115, 22, 0.3);
}

.btn-quaternary:hover {
    box-shadow: 0 15px 30px rgba(249, 115, 22, 0.5);
}

.btn-quinary {
    background: var(--quinary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(34, 197, 94, 0.3);
}

.btn-quinary:hover {
    box-shadow: 0 15px 30px rgba(34, 197, 94, 0.5);
}

.btn-senary {
    background: var(--senary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(14, 165, 233, 0.3);
}

.btn-senary:hover {
    box-shadow: 0 15px 30px rgba(14, 165, 233, 0.5);
}

.btn-septenary {
    background: var(--septenary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(239, 68, 68, 0.3);
}

.btn-septenary:hover {
    box-shadow: 0 15px 30px rgba(239, 68, 68, 0.5);
}

.btn-octonary {
    background: var(--octonary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(139, 92, 246, 0.3);
}

.btn-octonary:hover {
    box-shadow: 0 15px 30px rgba(139, 92, 246, 0.5);
}

.btn-nonary {
    background: var(--nonary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(6, 182, 212, 0.3);
}

.btn-nonary:hover {
    box-shadow: 0 15px 30px rgba(6, 182, 212, 0.5);
}

.btn-denary {
    background: var(--denary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(244, 63, 94, 0.3);
}

.btn-denary:hover {
    box-shadow: 0 15px 30px rgba(244, 63, 94, 0.5);
}

.btn-undenary {
    background: var(--undenary-gradient);
    border: none;
    box-shadow: 0 10px 20px rgba(20, 184, 166, 0.3);
}

.btn-undenary:hover {
    box-shadow: 0 15px 30px rgba(20, 184, 166, 0.5);
}

.btn-empty {
    background: var(--empty-gradient);
    border: 1px dashed rgba(255, 255, 255, 0.2);
}

.btn-empty:hover {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.4);
}

.icon {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.2));
}

.title {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: 1px;
}

.note {
    font-size: 0.85rem;
    font-weight: 300;
    margin-top: 0.5rem;
    opacity: 0.9;
    text-align: center;
    line-height: 1.2;
}

/* Responsiveness */
@media (max-width: 768px) {
    .container {
        padding: 1.5rem;
    }
    header h1 { font-size: 1.5rem; }
    header h2 { font-size: 2.2rem; }
    .grid-container {
        grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
        gap: 1rem;
    }
    .card {
        height: 140px;
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    header {
        margin-bottom: 2rem;
    }
    header h1 { font-size: 1.25rem; }
    header h2 { font-size: 1.8rem; }
    header p { font-size: 1rem; }
    
    .grid-container {
        grid-template-columns: 1fr; /* 1 column on small smartphones */
        gap: 1rem;
    }
    .card {
        height: 120px;
        padding: 1rem;
        flex-direction: row;
        justify-content: flex-start;
        gap: 1rem;
    }
    .icon {
        font-size: 2rem;
        margin-bottom: 0;
    }
    .title {
        font-size: 1.1rem;
    }
}