:root {
    --primary-color: #6366f1;
    --danger-color: #ef4444;
    --success-color: #22c55e;
    --background-color: #f8fafc;
    --card-background: #ffffff;
    --text-color: #1e293b;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    padding: 1.5rem;
    width: 100%;
    max-width: 480px;
}

.card {
    background: var(--card-background);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

h1 {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.description {
    color: #64748b;
    margin-bottom: 1.5rem;
}

.input-group {
    position: relative;
    margin-bottom: 1.5rem;
}

input {
    width: 100%;
    padding: 0.75rem 1rem;
    padding-right: 3rem;
    border: 2px solid #e2e8f0;
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: all 0.2s;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.visibility-toggle {
    position: absolute;
    right: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.25rem;
}

.check-button {
    width: 100%;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
}

.check-button:hover {
    background-color: #4f46e5;
}

.check-button:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.spinner {
    display: none;
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid #ffffff;
    border-top-color: transparent;
    border-radius: 50%;
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: translateY(-50%) rotate(360deg); }
}

.result {
    margin-top: 1.5rem;
    padding: 1rem;
    border-radius: 0.5rem;
    display: none;
    align-items: center;
    gap: 0.75rem;
    text-align: left;
}

.result.danger {
    background-color: #fef2f2;
    border: 1px solid #fee2e2;
    color: var(--danger-color);
    display: flex;
}

.result.success {
    background-color: #f0fdf4;
    border: 1px solid #dcfce7;
    color: var(--success-color);
    display: flex;
}

.result-icon {
    font-size: 1.5rem;
}

.result-text {
    font-size: 0.875rem;
    font-weight: 500;
}

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

.result.animate {
    animation: fadeIn 0.3s ease-out;
}

.password-strength-bar {
    width: 100%;
    height: 1rem;
    margin-top: 1.5rem;
    background: #eee;
    border-radius: 4px;
    overflow: hidden;
}

.password-strength-bar-fill {
    height: 100%;
    width: 0%;
    border-radius: 4px;
    transition: all 0.3s ease;
}

.password-strength-bar-fill.weak {
    width: 25%;
    background: #ef4444;
}

.password-strength-bar-fill.fair {
    width: 50%;
    background: #f97316;
}

.password-strength-bar-fill.good {
    width: 75%;
    background: #f97316;
}

.password-strength-bar-fill.strong {
    width: 100%;
    background: #22c55e;
}

footer {
    margin-top: 2rem;
    text-align: center;
    color: #666;
    font-size: 0.9rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    align-items: center;
}

footer a {
    font-weight: 700;
    color: #666;
    transition: color 0.2s ease;
}

footer a:hover {
    color: #333;
}

.github-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    background: #f5f5f5;
    transition: background 0.2s ease;
}

.github-link:hover {
    background: #eee;
}

.github-icon {
    color: #333;
}

.npm-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    background: #f5f5f5;
    transition: background 0.2s ease;
}

.npm-link:hover {
    background: #eee;
}

.npm-icon {
    color: #333;
}

.info-link {
    font-size: 0.85rem;
    text-decoration: underline;
    opacity: 0.8;
}

.info-link:hover {
    opacity: 1;
}

#confetti {
    pointer-events: none
}

.warning-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
    z-index: 1000;
    animation: pulse 1s ease-in-out infinite;
    background: rgba(255, 0, 0, 0.1);
}

.warning-light {
    position: absolute;
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255,0,0,0.8) 0%, rgba(255,0,0,0) 70%);
    animation: rotate 2s linear infinite;
}

.warning-light:nth-child(1) {
    top: 0;
    left: 0;
    animation-delay: 0s;
}

.warning-light:nth-child(2) {
    top: 0;
    right: 0;
    animation-delay: 0.5s;
}

.warning-light:nth-child(3) {
    bottom: 0;
    left: 0;
    animation-delay: 1s;
}

.warning-light:nth-child(4) {
    bottom: 0;
    right: 0;
    animation-delay: 1.5s;
}

@keyframes pulse {
    0% { background: rgba(255, 0, 0, 0.1); }
    50% { background: rgba(255, 0, 0, 0.2); }
    100% { background: rgba(255, 0, 0, 0.1); }
}

@keyframes rotate {
    0% { transform: scale(0.8); opacity: 0.8; }
    50% { transform: scale(1.2); opacity: 0.5; }
    100% { transform: scale(0.8); opacity: 0.8; }
}

.warning-overlay.fade-out {
    animation: fadeOut 0.5s forwards;
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

.result.danger {
    animation: shake 0.5s cubic-bezier(.36,.07,.19,.97) both;
}

@keyframes shake {
    10%, 90% { transform: translate3d(-1px, 0, 0); }
    20%, 80% { transform: translate3d(2px, 0, 0); }
    30%, 50%, 70% { transform: translate3d(-4px, 0, 0); }
    40%, 60% { transform: translate3d(4px, 0, 0); }
}