/* DSCR Calculator Styles
   Clean, professional, mobile-first design
   Author: DSCR Calculator Team */

:root {
    --color-primary: #0f3460;
    --color-primary-dark: #0a2342;
    --color-primary-light: #1a5490;
    --color-accent: #16a34a;
    --color-accent-light: #22c55e;
    --color-warning: #f59e0b;
    --color-danger: #dc2626;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-border: #e5e7eb;
    --color-input-bg: #ffffff;
    --shadow-sm: 0 1px 2px 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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: 200ms ease;
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-mono: "SF Mono", Monaco, Consolas, "Courier New", monospace;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.25rem;
}

/* Header */
.site-header {
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

.site-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    padding-bottom: 1rem;
}

.logo {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--color-primary);
    text-decoration: none;
    letter-spacing: -0.02em;
}

.logo span {
    color: var(--color-primary-light);
    font-weight: 500;
}

.main-nav {
    display: flex;
    gap: 1.75rem;
    align-items: center;
}

.main-nav a {
    color: var(--color-text);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: color var(--transition);
}

.main-nav a:hover {
    color: var(--color-primary);
}

@media (max-width: 640px) {
    .main-nav {
        display: none;
    }
}

/* Hero */
.hero {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    padding: 4rem 0 3.5rem;
    text-align: center;
}

.hero h1 {
    font-size: 2.75rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: 0.75rem;
}

.hero-subtitle {
    font-size: 1.15rem;
    opacity: 0.92;
    max-width: 680px;
    margin: 0 auto;
    font-weight: 400;
}

@media (max-width: 640px) {
    .hero {
        padding: 2.5rem 0 2rem;
    }
    .hero h1 {
        font-size: 2rem;
    }
    .hero-subtitle {
        font-size: 1rem;
    }
}

/* Calculator */
.calculator-section {
    padding: 3rem 0;
    background: var(--color-bg-alt);
}

.calculator-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    background: var(--color-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 2rem;
    border: 1px solid var(--color-border);
}

@media (max-width: 900px) {
    .calculator-wrapper {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        padding: 1.5rem;
    }
}

.calc-inputs h2,
.calc-results h2 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 1.25rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--color-border);
}

/* Input Groups */
.input-group {
    margin-bottom: 1.1rem;
}

.input-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 0.4rem;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    background: var(--color-input-bg);
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: border-color var(--transition), box-shadow var(--transition);
}

.input-wrapper:focus-within {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(15, 52, 96, 0.1);
}

.input-wrapper input {
    flex: 1;
    border: none;
    background: transparent;
    padding: 0.7rem 0.85rem;
    font-size: 1rem;
    font-family: var(--font-sans);
    color: var(--color-text);
    font-weight: 500;
    outline: none;
    width: 100%;
    min-width: 0;
}

.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;
}

.input-prefix,
.input-suffix {
    color: var(--color-text-light);
    font-weight: 500;
    padding: 0 0.85rem;
    font-size: 0.95rem;
    user-select: none;
}

.input-prefix {
    border-right: 1px solid var(--color-border);
}

.input-suffix {
    border-left: 1px solid var(--color-border);
}

.input-helper {
    font-size: 0.8rem;
    color: var(--color-text-light);
    margin-top: 0.3rem;
    padding-left: 0.2rem;
}

/* Results */
.result-card {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    text-align: center;
    transition: transform var(--transition), box-shadow var(--transition);
}

.result-card.primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    padding: 2rem 1.5rem;
    margin-bottom: 1.25rem;
    border: none;
    box-shadow: var(--shadow-md);
}

.result-label {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    opacity: 0.85;
    margin-bottom: 0.5rem;
}

.result-value {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 0.5rem;
    letter-spacing: -0.03em;
}

.result-value-small {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    letter-spacing: -0.02em;
}

.result-status {
    font-size: 0.95rem;
    font-weight: 500;
    opacity: 0.95;
    padding: 0.4rem 0.85rem;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 999px;
    display: inline-block;
    margin-top: 0.5rem;
}

.result-status.pass {
    background: rgba(34, 197, 94, 0.25);
}

.result-status.warn {
    background: rgba(245, 158, 11, 0.25);
}

.result-status.fail {
    background: rgba(220, 38, 38, 0.25);
}

.result-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.result-grid .result-card {
    padding: 1rem 0.75rem;
}

.result-grid .result-value-small {
    font-size: 1.2rem;
}

@media (max-width: 480px) {
    .result-grid {
        grid-template-columns: 1fr;
    }
}

.result-details {
    background: var(--color-bg-alt);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    margin-bottom: 1rem;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    font-size: 0.92rem;
    border-bottom: 1px solid var(--color-border);
}

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

.detail-row span:first-child {
    color: var(--color-text-light);
}

.detail-row span:last-child {
    font-weight: 600;
    color: var(--color-text);
}

.disclaimer-mini {
    font-size: 0.8rem;
    color: var(--color-text-light);
    text-align: center;
    padding: 0.85rem;
    background: var(--color-bg-alt);
    border-radius: var(--radius-sm);
    line-height: 1.5;
}

/* Content Sections */
.content-section {
    padding: 4rem 0;
}

.content-section.alt-bg {
    background: var(--color-bg-alt);
}

.content-section h2 {
    font-size: 2rem;
    font-weight: 800;
    color: var(--color-primary);
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
}

.content-section h3 {
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--color-primary-dark);
    margin: 1.75rem 0 0.75rem;
}

.content-section p {
    font-size: 1.05rem;
    line-height: 1.7;
    margin-bottom: 1rem;
    color: var(--color-text);
}

.content-section ul {
    margin: 1rem 0 1.25rem 1.5rem;
}

.content-section li {
    font-size: 1.02rem;
    line-height: 1.7;
    margin-bottom: 0.5rem;
    color: var(--color-text);
}

.content-section strong {
    color: var(--color-primary-dark);
    font-weight: 700;
}

.content-section em {
    color: var(--color-primary);
    font-style: italic;
}

@media (max-width: 640px) {
    .content-section {
        padding: 2.5rem 0;
    }
    .content-section h2 {
        font-size: 1.6rem;
    }
    .content-section h3 {
        font-size: 1.2rem;
    }
}

/* Formula Box */
.formula-box {
    background: linear-gradient(135deg, #f0f4f8 0%, #e6edf3 100%);
    border-left: 4px solid var(--color-primary);
    border-radius: var(--radius-sm);
    padding: 1.25rem 1.5rem;
    margin: 1.25rem 0;
    overflow-x: auto;
}

.formula-box code {
    font-family: var(--font-mono);
    font-size: 1.05rem;
    color: var(--color-primary-dark);
    font-weight: 600;
    white-space: nowrap;
}

/* FAQ */
.faq-item {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: box-shadow var(--transition);
}

.faq-item:hover {
    box-shadow: var(--shadow-sm);
}

.faq-item h3 {
    font-size: 1.1rem;
    margin-top: 0;
    margin-bottom: 0.5rem;
    color: var(--color-primary-dark);
}

.faq-item p {
    font-size: 0.98rem;
    margin-bottom: 0;
}

/* Disclaimer */
.disclaimer {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-left: 4px solid var(--color-warning);
    border-radius: var(--radius-md);
    padding: 2rem;
}

.disclaimer h3 {
    color: var(--color-warning);
    margin-top: 0;
}

.disclaimer p:last-child {
    margin-bottom: 0;
}

/* Footer */
.site-footer {
    background: var(--color-primary-dark);
    color: white;
    padding: 2.5rem 0 2rem;
}

.site-footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.site-footer p {
    margin: 0;
    opacity: 0.85;
    font-size: 0.9rem;
}

.footer-nav {
    display: flex;
    gap: 1.5rem;
}

.footer-nav a {
    color: white;
    text-decoration: none;
    font-size: 0.9rem;
    opacity: 0.85;
    transition: opacity var(--transition);
}

.footer-nav a:hover {
    opacity: 1;
}

@media (max-width: 640px) {
    .site-footer .container {
        flex-direction: column;
        text-align: center;
    }
}