:root {
    --primary-color: #1DA1F2;
    --secondary-color: #14171A;
    --success-color: #17BF63;
    --danger-color: #E1245E;
    --light-gray: #F7F9FA;
    --dark-bg: #0f1419;
}

body {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

.navbar {
    background-color: rgba(29, 161, 242, 0.95) !important;
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar-brand {
    font-size: 1.5rem;
    display: flex;
    align-items: center;
}

.navbar-brand img{
    width: 4rem;
    height: 4rem;
    padding: 5px;
}

.container {
    max-width: 1200px;
    padding: 20px;
}

header h1 {
    color: white;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

header .lead {
    color: rgba(255,255,255,0.9) !important;
}

.card {
    border: none;
    border-radius: 15px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.15) !important;
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    border-radius: 50px;
    padding: 12px 30px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: #1a91da;
    border-color: #1a91da;
    transform: translateY(-2px);
}

.btn-primary:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.btn-xl {
    padding: 16px 32px;
    font-size: 1.2rem;
    font-weight: 600;
    border-radius: 12px;
    min-height: 56px;
}

.form-control {
    border-radius: 10px;
    border: 2px solid #e1e8ed;
    padding: 12px 15px;
    transition: border-color 0.3s ease;
}

.form-control-xl {
    padding: 20px 60px 20px 20px;
    font-size: 1.1rem;
    border-radius: 12px;
    border: 2px solid #dee2e6;
    min-height: 60px;
}

.form-control:focus,
.form-control-xl:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(29, 161, 242, 0.25);
    outline: none;
}

#results .card-header {
    background: linear-gradient(135deg, #17BF63 0%, #14A85F 100%);
    font-weight: 600;
}

.format-item {
    border: 1px solid #e1e8ed;
    border-radius: 10px;
    padding: 15px;
    margin-bottom: 10px;
    transition: all 0.3s ease;
    background-color: white;
}

.format-item:hover {
    background-color: var(--light-gray);
    border-color: var(--primary-color);
    transform: translateX(5px);
}

.download-btn {
    background-color: var(--success-color);
    color: white;
    border: none;
    border-radius: 20px;
    padding: 8px 20px;
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
    cursor: pointer;
    min-width: 120px;
}

.download-btn:hover:not(:disabled) {
    background-color: #14A85F;
    color: white;
    transform: scale(1.05);
}

.download-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.alert {
    border-radius: 10px;
    border: none;
}

.spinner-border-sm {
    width: 1rem;
    height: 1rem;
}

#thumbnail {
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

footer {
    color: rgba(255,255,255,0.8);
    border-top-color: rgba(255,255,255,0.1) !important;
}

/* How to Use Section */
.step-number {
    width: 60px;
    height: 60px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
    box-shadow: 0 4px 10px rgba(29, 161, 242, 0.3);
}

/* Features Section */
.feature-card {
    background: rgba(255,255,255,0.05);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.1);
    padding: 30px 20px;
    border-radius: 15px;
    text-align: center;
    color: white;
    transition: all 0.3s ease;
    height: 100%;
}

.feature-card:hover {
    transform: translateY(-5px);
    background: rgba(255,255,255,0.08);
    box-shadow: 0 10px 30px rgba(29, 161, 242, 0.2);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.feature-card h5 {
    color: white;
    margin-bottom: 15px;
}

.feature-card p {
    color: rgba(255,255,255,0.7);
    margin: 0;
}

/* FAQ Section */
.accordion-item {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    margin-bottom: 10px;
    border-radius: 10px !important;
    overflow: hidden;
}

.accordion-button {
    background: transparent;
    color: white;
    font-weight: 600;
}

.accordion-button:not(.collapsed) {
    background: rgba(29, 161, 242, 0.1);
    color: white;
}

.accordion-button:focus {
    box-shadow: none;
    border-color: rgba(29, 161, 242, 0.5);
}

.accordion-body {
    background: rgba(255,255,255,0.02);
    color: rgba(255,255,255,0.8);
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .card-body {
        padding: 15px;
    }
    
    .feature-card {
        margin-bottom: 20px;
    }
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.fade-in {
    animation: fadeIn 0.5s ease-in;
}

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

/* Input Wrapper and Paste Button Styles */
.input-wrapper {
    position: relative;
}

.paste-icon-btn {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    background: transparent;
    border: none;
    padding: 8px;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    z-index: 10;
    color: #6c757d;
}

.paste-icon-btn:hover {
    background-color: #f8f9fa;
    color: #495057;
}

.paste-icon-btn:active {
    background-color: #e9ecef;
    transform: translateY(-50%) scale(0.95);
}

.paste-icon-btn svg {
    pointer-events: none;
}