:root {
    --bg-color: #f3f4f6;
    --card-bg: #ffffff;
    --text-main: #111827;
    --text-muted: #4b5563;
    --accent-gradient: linear-gradient(135deg, #004b87 0%, #002855 100%);
    --input-bg: #ffffff;
    --border-color: #d1d5db;
    --glass-border: rgba(0, 0, 0, 0.05);
    --primary-color: #004b87;
    --text-color: #111827;
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-image: 
        radial-gradient(at 0% 0%, rgba(0, 75, 135, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(251, 176, 52, 0.1) 0px, transparent 50%);
}

.container {
    width: 100%;
    max-width: 800px;
    padding: 2rem;
    box-sizing: border-box;
}

h1 {
    font-size: 2.5rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 2rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.025em;
}

.card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 1.5rem;
    padding: 2.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

h2 {
    font-size: 1.25rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: var(--text-main);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

h2:first-of-type {
    margin-top: 0;
}

.tshirt-item {
    background: rgba(0, 0, 0, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 1rem;
    position: relative;
    transition: transform 0.2s, border-color 0.2s;
    animation: fadeIn 0.3s ease-out;
}

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

.tshirt-item:hover {
    border-color: var(--primary-color);
}

.grid-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-bottom: 1rem;
}

label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

select, input {
    width: 100%;
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    font-size: 1rem;
    transition: all 0.2s;
    box-sizing: border-box;
}

select:focus, input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 75, 135, 0.2);
}

.btn {
    padding: 0.75rem 1.5rem;
    border-radius: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    font-size: 0.95rem;
}

.btn-secondary {
    background: rgba(0, 0, 0, 0.05);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    width: 100%;
}

.btn-secondary:hover {
    background: rgba(0, 0, 0, 0.1);
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    width: 100%;
    margin-top: 2rem;
    font-size: 1.1rem;
    padding: 1rem;
    box-shadow: 0 10px 15px -3px rgba(0, 75, 135, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(0, 75, 135, 0.4);
}

.btn-remove {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: transparent;
    color: #ef4444;
    border: none;
    cursor: pointer;
    font-size: 1.25rem;
    padding: 0.25rem;
    line-height: 1;
    opacity: 0.7;
}

.btn-remove:hover {
    opacity: 1;
    transform: scale(1.1);
}

.price-display {
    text-align: right;
    font-weight: 700;
    color: var(--primary-color);
    font-size: 1.1rem;
    margin-top: 0.5rem;
}

.total-section {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 800;
}

.error-msg {
    color: #ef4444;
    font-size: 0.875rem;
    margin-top: 0.25rem;
    display: none;
}