:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    --bg-color: #f3f4f6;
    --glass-bg: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(255, 255, 255, 0.5);
    --text-primary: #1f2937;
    --text-secondary: #4b5563;
    --accent-color: #4f46e5;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    background-image:
        radial-gradient(at 0% 0%, hsla(253, 16%, 7%, 1) 0, transparent 50%),
        radial-gradient(at 50% 0%, hsla(225, 39%, 30%, 1) 0, transparent 50%),
        radial-gradient(at 100% 0%, hsla(339, 49%, 30%, 1) 0, transparent 50%);
    background-size: cover;
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem;
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    border-radius: 1rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--glass-border);
}

h1 {
    font-size: 2.5rem;
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    /* Fallback */
    margin-bottom: 1rem;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* Main Tool */
.converter-card {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    border-radius: 1.5rem;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--glass-border);
    margin-bottom: 3rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: start;
}

@media (max-width: 768px) {
    .converter-card {
        grid-template-columns: 1fr;
        padding: 1.5rem;
    }
}

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

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

input[type="number"] {
    width: 100%;
    padding: 1rem;
    font-size: 1.25rem;
    border: 2px solid #e5e7eb;
    border-radius: 0.75rem;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.9);
}

input[type="number"]:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.unit-label {
    position: absolute;
    right: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.divider {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 1rem 0;
}

.icon {
    width: 24px;
    height: 24px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

/* Preview Section */
.preview-section {
    background: rgba(255, 255, 255, 0.5);
    padding: 2rem;
    border-radius: 1rem;
    border: 1px dashed var(--accent-color);
}

.preview-title {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-weight: 700;
}

.preview-box {
    margin-top: 1rem;
    padding: 1rem;
    background: white;
    border-radius: 0.5rem;
    box-shadow: var(--shadow-sm);
    transition: all 0.2s;
    min-height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
}

/* Common Table */
.data-table-section {
    margin-top: 3rem;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.data-table th,
.data-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid #e5e7eb;
}

.data-table th {
    background: #f9fafb;
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.data-table tr:last-child td {
    border-bottom: none;
}

.data-table td a {
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 500;
}

.data-table td a:hover {
    text-decoration: underline;
}

/* Content Section */
.content-section {
    background: white;
    padding: 3rem;
    border-radius: 1.5rem;
    margin-top: 3rem;
    box-shadow: var(--shadow-lg);
}

.content-section h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: #111827;
}

.content-section p {
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    font-size: 1.125rem;
}

/* Footer */
footer {
    text-align: center;
    margin-top: 4rem;
    padding: 2rem;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.875rem;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.contact-card {
    background: rgba(255, 255, 255, 0.1);
    padding: 1.5rem;
    border-radius: 1rem;
    backdrop-filter: blur(5px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-copy {
    margin-top: 0.5rem;
    padding: 0.5rem 1rem;
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    width: 100%;
}

.btn-copy:hover {
    background: #f9fafb;
}

/* Ad Placeholders */
.ad-slot {
    margin: 2rem 0;
    text-align: center;
    background: rgba(0, 0, 0, 0.02);
    padding: 1rem;
    border-radius: 0.5rem;
}