/* DIYCalcs.com Design System */
:root {
    /* Industrial Theme Palette */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --accent-color: #f97316;
    --accent-hover: #ea580c;
    --border-color: #cbd5e1;
    --card-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);

    /* Typography */
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
    --radius-md: 8px;
    --radius-lg: 12px;
}

/* Dark Mode Overrides */
[data-theme="dark"] {
    --bg-primary: #0f172a;
    /* Slate 900 */
    --bg-secondary: #1e293b;
    /* Slate 800 */
    --text-primary: #f1f5f9;
    /* Slate 100 */
    --text-secondary: #94a3b8;
    /* Slate 400 */
    --border-color: #334155;
    /* Slate 700 */
    --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
}

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #0f172a;
        /* Slate 900 */
        --bg-secondary: #1e293b;
        /* Slate 800 */
        --text-primary: #f1f5f9;
        --text-secondary: #94a3b8;
        --border-color: #334155;
    }
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Typography */
h1,
h2,
h3 {
    line-height: 1.2;
    font-weight: 700;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: 800;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo span {
    color: var(--accent-color);
}

/* Grid Layout for Tools */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
    padding: 40px 0;
}

@media (max-width: 640px) {
    .tools-grid {
        grid-template-columns: 1fr;
        gap: 16px;
        padding: 20px 0;
    }

    .container {
        padding: 0 16px;
    }

    h1 {
        font-size: 32px !important;
    }
}

/* Card Component */
.tool-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 24px;
    transition: transform 0.2s, box-shadow 0.2s;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--card-shadow);
    border-color: var(--accent-color);
}

.tool-icon {
    width: 48px;
    height: 48px;
    background: rgba(249, 115, 22, 0.1);
    color: var(--accent-color);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 8px;
}

/* Calculator Form Styles */
.calculator-section {
    max-width: 600px;
    margin: 40px auto;
    background: var(--bg-secondary);
    padding: 30px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--card-shadow);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    font-size: 14px;
    color: var(--text-secondary);
}

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

.input-wrapper i {
    position: absolute;
    left: 12px;
    color: var(--text-secondary);
    width: 18px;
    height: 18px;
}

.form-control {
    width: 100%;
    padding: 12px 12px 12px 40px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 16px;
    transition: all 0.2s;
}

.form-control:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(249, 115, 22, 0.1);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-size: 16px;
}

.btn-primary {
    background: var(--accent-color);
    color: white;
    width: 100%;
}

.btn-primary:hover {
    background: var(--accent-hover);
}

.btn-secondary {
    background: transparent;
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    width: 100%;
}

.btn-secondary:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

/* Result Box */
.result-box {
    margin-top: 30px;
    background: rgba(249, 115, 22, 0.05);
    /* Very light orange tint */
    border: 1px solid rgba(249, 115, 22, 0.2);
    border-radius: var(--radius-md);
    padding: 20px;
    display: none;
    /* Hidden by default */
}

.result-box.show {
    display: block;
    animation: fadeIn 0.3s ease-out;
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed var(--border-color);
}

.result-row:last-child {
    border-bottom: none;
}

.result-val {
    font-weight: 700;
    font-size: 18px;
    color: var(--accent-color);
}

.footer {
    margin-top: auto;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 40px 0;
    text-align: center;
    color: var(--text-secondary);
}

/* Article Grid for Guides */
.article-grid {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 50px;
}

@media (max-width: 900px) {
    .article-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .sidebar-sticky {
        position: static;
    }
}