:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --background: #0f172a;
    --surface: #1e293b;
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --border: #334155;
    --error: #ef4444;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--background);
    color: var(--text);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    width: 100%;
    max-width: 500px;
    padding: 2rem;
    text-align: center;
}

header {
    margin-bottom: 3rem;
}

h1 {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, #818cf8 0%, #c084fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

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

.card {
    background-color: var(--surface);
    padding: 2.5rem;
    border-radius: 1rem;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
    border: 1px solid var(--border);
}

.form-group {
    margin-bottom: 1.5rem;
    text-align: left;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-muted);
}

input {
    width: 100%;
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
    background-color: var(--background);
    color: var(--text);
    font-size: 1rem;
    transition: border-color 0.2s;
}

input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.input-group {
    display: flex;
    align-items: center;
}

/* Suffix Handling (Old) - Keeping if needed or removing? 
   Let's replace with Prefix handling */

.input-group input {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

.prefix {
    padding: 0.75rem 1rem;
    background-color: var(--border);
    border: 1px solid var(--border);
    border-right: none;
    border-top-left-radius: 0.5rem;
    border-bottom-left-radius: 0.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
    user-select: none;
}

button[type="submit"] {
    width: 100%;
    padding: 1rem;
    background-color: var(--primary);
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}

button[type="submit"]:hover {
    background-color: var(--primary-hover);
}

.hidden {
    display: none;
}

#result {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    animation: fadeIn 0.5s ease;
}

#shortUrl {
    display: block;
    font-size: 1.25rem;
    color: var(--primary);
    text-decoration: none;
    margin: 1rem 0;
    word-break: break-all;
}

#shortUrl:hover {
    text-decoration: underline;
}

#copyBtn {
    background-color: transparent;
    border: 1px solid var(--border);
    color: var(--text);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
}

#copyBtn:hover {
    background-color: var(--border);
}

#error {
    margin-top: 1.5rem;
    color: var(--error);
    font-size: 0.9rem;
}

footer {
    margin-top: 3rem;
    color: var(--text-muted);
    font-size: 0.8rem;
}

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

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