:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #ec4899;
    --bg-gradient-start: #0f172a;
    --bg-gradient-end: #1e1b4b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    --input-bg: rgba(15, 23, 42, 0.6);
    --input-focus: rgba(99, 102, 241, 0.3);
}

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

body {
    font-family: 'Outfit', sans-serif;
    background: linear-gradient(135deg, var(--bg-gradient-start), var(--bg-gradient-end));
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
    position: relative;
}

/* Background Abstract Shapes */
.background-shapes .shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    z-index: -1;
    opacity: 0.5;
}

.shape-1 {
    width: 300px;
    height: 300px;
    background: var(--primary-color);
    top: -50px;
    left: -50px;
    animation: float 10s infinite ease-in-out;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: var(--secondary-color);
    bottom: -100px;
    right: -100px;
    animation: float 12s infinite ease-in-out reverse;
}

.shape-3 {
    width: 200px;
    height: 200px;
    background: #8b5cf6;
    top: 40%;
    left: 40%;
    animation: float 15s infinite ease-in-out 2s;
}

@keyframes float {
    0% { transform: translate(0, 0); }
    50% { transform: translate(20px, 40px); }
    100% { transform: translate(0, 0); }
}

.container {
    width: 100%;
    max-width: 600px;
    padding: 20px;
    z-index: 10;
}

.app-header {
    text-align: center;
    margin-bottom: 2rem;
}

.app-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(to right, #c084fc, #ec4899);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

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

/* Glass Card */
.card.glass {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: var(--glass-shadow);
    transition: transform 0.3s ease;
}

/* Form Elements */
.form-group {
    margin-bottom: 1.5rem;
    opacity: 0;
    animation: fadeIn 0.5s forwards;
}

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

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #e2e8f0;
}

.select-wrapper, .input-wrapper {
    position: relative;
}

select, input {
    width: 100%;
    padding: 1rem;
    background: var(--input-bg);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    color: white;
    font-size: 1rem;
    font-family: inherit;
    outline: none;
    transition: all 0.3s ease;
    appearance: none;
    -webkit-appearance: none;
}

select:focus, input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px var(--input-focus);
}

.select-wrapper::after {
    content: '▼';
    font-size: 0.8rem;
    color: var(--text-muted);
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    pointer-events: none;
}

.unit {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-weight: 500;
}

/* Buttons */
.form-actions {
    margin-top: 2rem;
    display: flex;
    justify-content: flex-end;
}

.btn-primary, .btn-secondary {
    padding: 1rem 2rem;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: 0 4px 15px rgba(236, 72, 153, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(236, 72, 153, 0.6);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* Result Area */
.result-card {
    text-align: center;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--card-border);
    animation: slideUp 0.5s ease;
}

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

.result-card h2 {
    color: var(--text-muted);
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 1rem;
}

.result-text {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    line-height: 1.4;
    background: linear-gradient(to right, #4ade80, #2dd4bf);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hidden {
    display: none;
}

footer {
    text-align: center;
    margin-top: 2rem;
    color: rgba(255, 255, 255, 0.4);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 480px) {
    .card.glass {
        padding: 1.5rem;
    }
    
    .app-header h1 {
        font-size: 2rem;
    }
}