:root {
    --primary-color: #6366f1; /* Indigo */
    --secondary-color: #ec4899; /* Pink */
    --background-start: #0f172a;
    --background-end: #1e1b4b;
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --input-bg: rgba(15, 23, 42, 0.5);
    --focus-ring: rgba(99, 102, 241, 0.6);
}

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

body {
    font-family: 'Outfit', sans-serif;
    background: var(--background-start);
    color: var(--text-primary);
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

.background-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    overflow: hidden;
    pointer-events: none;
}

.background-animation::before,
.background-animation::after {
    content: '';
    position: absolute;
    width: 50vw;
    height: 50vw;
    border-radius: 50%;
    filter: blur(100px);
    animation: float 20s infinite ease-in-out alternate;
    opacity: 0.6;
}

.background-animation::before {
    background: var(--primary-color);
    top: -10%;
    left: -10%;
    animation-delay: 0s;
}

.background-animation::after {
    background: var(--secondary-color);
    bottom: -10%;
    right: -10%;
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(20%, 20%) scale(1.2); }
}

.scroll-container {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 4rem 1rem;
    gap: 3rem;
    max-width: 800px;
    margin: 0 auto;
}

.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 3rem;
    width: 100%;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.calculator-container:hover {
    transform: translateY(-5px);
    box-shadow: 0 30px 60px -12px rgba(0, 0, 0, 0.6);
}

/* Header & Calculator specifics */
header {
    text-align: center;
    margin-bottom: 2.5rem;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #a5b4fc, #fbcfe8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 300;
}

.converter-box {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    max-width: 480px;
    margin: 0 auto;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.input-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-secondary);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    transition: transform 0.15s ease-out;
}

.input-wrapper input {
    width: 100%;
    background: var(--input-bg);
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    padding: 1rem 3.5rem 1rem 1.5rem;
    color: var(--text-primary);
    font-size: 1.25rem;
    font-family: 'Outfit', sans-serif;
    font-weight: 600;
    outline: none;
    transition: all 0.3s ease;
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.2);
}

.input-wrapper input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px var(--focus-ring), inset 0 2px 4px rgba(0,0,0,0.2);
}

.input-wrapper input::placeholder {
    color: #475569;
    font-weight: 400;
}

/* Hide arrow for number input */
.input-wrapper input::-webkit-outer-spin-button,
.input-wrapper input::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.input-wrapper input[type=number] {
    -moz-appearance: textfield;
}

.unit-badge {
    position: absolute;
    right: 1rem;
    color: var(--text-secondary);
    font-weight: 600;
    pointer-events: none;
    background: rgba(255,255,255,0.1);
    padding: 0.2rem 0.6rem;
    border-radius: 6px;
    font-size: 0.85rem;
}

.icon-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 1rem;
    position: relative;
    margin: 0.5rem 0;
}

.icon-wrapper svg {
    width: 32px;
    height: 32px;
    color: var(--text-secondary);
    background: var(--input-bg);
    border-radius: 50%;
    padding: 6px;
    border: 1px solid var(--glass-border);
    position: absolute;
    z-index: 2;
    transition: transform 0.3s ease, color 0.3s ease;
}

.calculator-container:hover .icon-wrapper svg {
    color: var(--secondary-color);
    transform: rotate(90deg);
}

.quick-facts {
    margin-top: 2.5rem;
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid var(--glass-border);
}

.quick-facts p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    opacity: 0.8;
}

.quick-facts strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* SEO Article Styles */
.seo-article {
    line-height: 1.8;
}

.seo-article h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: #fbcfe8;
}

.seo-article h3 {
    font-size: 1.4rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: #a5b4fc;
}

.seo-article p {
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    font-size: 1.05rem;
}

.seo-article ol {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
    color: var(--text-secondary);
}

.seo-article li {
    margin-bottom: 0.8rem;
}

.seo-article li strong {
    color: var(--text-primary);
}

.article-image {
    width: 100%;
    height: auto;
    border-radius: 16px;
    margin: 2rem 0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    border: 1px solid var(--glass-border);
}

/* FAQ Styles */
.faq-section h2 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    text-align: center;
    color: #fbcfe8;
}

.faq-item {
    background: rgba(15, 23, 42, 0.4);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    margin-bottom: 1rem;
    overflow: hidden;
    transition: all 0.3s ease;
}

.faq-item:hover {
    border-color: rgba(99, 102, 241, 0.5);
}

.faq-item summary {
    padding: 1.5rem;
    font-weight: 600;
    font-size: 1.1rem;
    cursor: pointer;
    list-style: none;
    position: relative;
    color: var(--text-primary);
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item summary::after {
    content: '+';
    position: absolute;
    right: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.5rem;
    color: var(--primary-color);
    transition: transform 0.3s ease;
}

.faq-item[open] summary::after {
    content: '−';
}

.faq-content {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-secondary);
    line-height: 1.6;
    border-top: 1px solid rgba(255,255,255,0.05);
    margin-top: 0.5rem;
    padding-top: 1rem;
}

footer {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
    opacity: 0.7;
    margin-top: 2rem;
}

/* Responsive */
@media (max-width: 600px) {
    .glass-card {
        padding: 2rem;
        border-radius: 20px;
    }
    
    header h1 {
        font-size: 1.75rem;
    }
    
    .seo-article h2 {
        font-size: 1.5rem;
    }
}