:root {
    /* Paleta de Cores e Escala de Espaçamento */
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --dark: #0f172a;
    --dark-lighter: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #22c55e;
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
    --spacing-xl: 48px;
}

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

body {
    background-color: var(--dark);
    color: var(--text-main);
    line-height: 1.6;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Nav */
nav {
    height: 90px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid rgba(255,255,255,0.05);
}

.nav-content {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.75rem;
    font-weight: 800;
    letter-spacing: -1.5px;
}

.logo span { color: var(--primary); }

/* Hero */
header {
    padding: var(--spacing-xl) 0;
    text-align: center;
}

h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
    letter-spacing: -2.5px;
}

h1 span { color: var(--primary); }

/* Card Shortener - O Câmbio Principal */
.card-shortener {
    background: var(--dark-lighter);
    padding: var(--spacing-xl); /* Espaçamento interno generoso */
    border-radius: 20px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(255,255,255,0.03);
    margin-bottom: var(--spacing-xl); /* Espaçamento externo para a área de resultado */
}

/* Garante espaçamento vertical entre as linhas de input */
.input-row {
    margin-bottom: var(--spacing-md);
}

input[type="url"], .pre-slug-input {
    width: 100%;
    padding: 18px 24px;
    border-radius: 12px;
    border: 2px solid transparent;
    background: var(--dark);
    color: white;
    font-size: 1.1rem;
    transition: 0.3s ease;
}

input:focus, .pre-slug-container.focus {
    outline: none;
    border-color: var(--primary);
}

/* Slug Customizado Integrado - Visual Profissional */
.pre-slug-container {
    display: flex;
    align-items: center;
    background: var(--dark);
    border-radius: 12px;
    border: 2px solid transparent;
    transition: 0.3s;
}

.pre-slug-container:focus-within {
    border-color: var(--primary);
}

.pre-slug-prefix {
    padding: 18px;
    color: var(--text-muted);
    border-right: 2px solid rgba(255,255,255,0.05);
    font-size: 1rem;
    white-space: nowrap;
}

.pre-slug-input {
    border: none !important; /* Remove bordas internas */
    border-radius: 0 12px 12px 0;
}

/* Botões */
.btn {
    width: 100%;
    padding: 18px 24px;
    border-radius: 12px;
    border: none;
    font-weight: 700;
    font-size: 1.2rem;
    cursor: pointer;
    transition: 0.3s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background: var(--primary);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-primary:disabled {
    background: var(--dark);
    cursor: not-allowed;
    color: var(--text-muted);
}

/* Results - Espaçoso e Limpo */
.result-area {
    margin-top: var(--spacing-xl);
    animation: fadeIn 0.6s ease;
}

.hidden { display: none; }

.result-card {
    background: rgba(34, 197, 94, 0.05);
    border: 2px solid var(--accent);
    padding: var(--spacing-lg); /* Padding generoso */
    border-radius: 15px;
}

.result-card p {
    color: var(--accent);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.result-controls {
    display: flex;
    gap: var(--spacing-sm);
}

#shortUrl {
    flex-grow: 1;
    background: rgba(0,0,0,0.2);
    border: 1px solid rgba(255,255,255,0.05);
    color: var(--text-muted);
}

.btn-accent {
    background: var(--accent);
    color: white;
    width: auto;
    font-size: 1rem;
}

/* Animações e Responsividade */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 768px) {
    h1 { font-size: 2.75rem; }
    .result-controls { flex-direction: column; }
    .btn-accent { width: 100%; }
}