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

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    width: 90%;
    max-width: 700px;
    padding: 2rem;
}

header {
    text-align: center;
    margin-bottom: 3rem;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(90deg, #e94560, #ff6b6b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

header p {
    color: #a0a0a0;
    font-size: 1.1rem;
}

.input-group {
    display: flex;
    gap: 1rem;
    background: rgba(255, 255, 255, 0.05);
    padding: 1rem;
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

input[type="url"] {
    flex: 1;
    padding: 1rem 1.5rem;
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.05);
    color: #fff;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.3s;
}

input[type="url"]:focus {
    border-color: #e94560;
}

input[type="url"]::placeholder {
    color: #666;
}

.btn-primary {
    padding: 1rem 2rem;
    border: none;
    border-radius: 12px;
    background: linear-gradient(135deg, #e94560 0%, #c23a4f 100%);
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    position: relative;
    overflow: hidden;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(233, 69, 96, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.loading {
    text-align: center;
    margin-top: 2rem;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.1);
    border-top-color: #e94560;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.hidden {
    display: none !important;
}

footer {
    text-align: center;
    margin-top: 3rem;
    color: #666;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 600px) {
    header h1 {
        font-size: 1.8rem;
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .btn-primary {
        width: 100%;
    }
}

/* Results Page */
.results-container {
    max-width: 900px;
}

.back-btn {
    display: inline-block;
    margin-bottom: 2rem;
    padding: 0.75rem 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
    text-decoration: none;
    border-radius: 8px;
    transition: background 0.3s;
}

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

.metrics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.metric-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 1.5rem;
    text-align: center;
}

.metric-card h3 {
    color: #a0a0a0;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.metric-value {
    font-size: 2rem;
    font-weight: 700;
}

.metric-value.good { color: #4ecca3; }
.metric-value.warning { color: #ffa502; }
.metric-value.bad { color: #ff6348; }

.url-display {
    background: rgba(255, 255, 255, 0.05);
    padding: 1rem 1.5rem;
    border-radius: 12px;
    margin-bottom: 2rem;
    border-left: 4px solid #e94560;
}

.url-display h2 {
    color: #a0a0a0;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.url-display p {
    font-size: 1.1rem;
    word-break: break-all;
}

.error {
    background: rgba(255, 99, 72, 0.1);
    border: 1px solid rgba(255, 99, 72, 0.3);
    border-radius: 12px;
    padding: 2rem;
    text-align: center;
    margin-top: 2rem;
}

.error h2 {
    color: #ff6348;
    margin-bottom: 1rem;
}