:root {
    --color-bg: #0f172a;
    --color-surface: #111c34;
    --color-card: #162447;
    --color-accent: #38bdf8;
    --color-accent-dark: #0ea5e9;
    --color-text: #f8fafc;
    --color-muted: #cbd5f5;
    --color-border: rgba(255, 255, 255, 0.12);
    --font-sans: "Inter", "Segoe UI", -apple-system, BlinkMacSystemFont, sans-serif;
    --shadow-soft: 0 20px 40px rgba(15, 23, 42, 0.35);
    --max-width: 1100px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: var(--font-sans);
    background: radial-gradient(circle at top, #1e293b, #0f172a 45%);
    color: var(--color-text);
    line-height: 1.6;
}

img {
    max-width: 100%;
}

.container {
    width: min(100% - 2.5rem, var(--max-width));
    margin-inline: auto;
}

.site-header {
    position: sticky;
    top: 0;
    backdrop-filter: blur(16px);
    background: rgba(15, 23, 42, 0.85);
    border-bottom: 1px solid var(--color-border);
    z-index: 10;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    font-weight: 700;
    text-decoration: none;
    color: var(--color-text);
    letter-spacing: 0.05em;
}

.main-nav {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    font-size: 0.95rem;
}

.main-nav a {
    color: var(--color-muted);
    text-decoration: none;
    transition: color 0.2s ease;
}

.main-nav a:hover,
.main-nav a:focus {
    color: var(--color-text);
}

.hero {
    padding: 6rem 0 4rem;
    /* Quick Win 2: Animated gradient background */
    background: linear-gradient(-45deg, #0f172a, #1e293b, #162447, #1e293b);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    position: relative;
    overflow: hidden;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero__content {
    display: grid;
    gap: 2.5rem;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    align-items: center;
}

.hero__text h1 {
    font-size: clamp(2.25rem, 2.5vw + 2rem, 3rem);
    margin-bottom: 1rem;
    /* Quick Win 1: Gradient text for WOW factor */
    background: linear-gradient(135deg, #38bdf8 0%, #818cf8 50%, #c084fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 800;
    letter-spacing: -0.02em;
    animation: gradientSlide 8s ease infinite;
    background-size: 200% auto;
}

@keyframes gradientSlide {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero__text p {
    max-width: 34ch;
    color: var(--color-muted);
    margin-bottom: 2rem;
}

.hero__card {
    /* Quick Win 4: Glassmorphism */
    background: linear-gradient(160deg, 
        rgba(22, 36, 71, 0.8), 
        rgba(56, 189, 248, 0.15));
    backdrop-filter: blur(15px);
    padding: 2.5rem;
    border-radius: 1.5rem;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.15);
    transition: all 0.3s ease;
}

.hero__card:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.5),
                0 0 30px rgba(56, 189, 248, 0.2);
}

.hero__card h2 {
    margin-top: 0;
    font-size: 1.25rem;
}

.hero__card ul {
    padding-left: 1.1rem;
}

.hero__card li {
    margin-bottom: 0.6rem;
}

/* Quick FAQ Section Styles */
.quick-faq {
    padding: 4rem 0;
    background: linear-gradient(135deg, var(--color-surface), var(--color-card));
}

.quick-faq h2 {
    text-align: center;
    margin-bottom: 3rem;
    color: var(--color-text);
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.faq-item {
    /* Quick Win 4: Glassmorphism cards */
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 1.5rem;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.faq-item:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(56, 189, 248, 0.4);
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 15px 45px rgba(0, 0, 0, 0.4),
                0 0 30px rgba(56, 189, 248, 0.2),
                inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

.faq-item h3 {
    color: var(--color-accent);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.faq-item p {
    margin: 0;
    line-height: 1.6;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.6rem;
    color: #0f172a;
    /* Quick Win 3: Premium 3D gradient button */
    background: linear-gradient(135deg, #38bdf8 0%, #0ea5e9 100%);
    box-shadow: 0 10px 30px rgba(56, 189, 248, 0.3), 
                0 4px 10px rgba(0, 0, 0, 0.2),
                inset 0 1px 0 rgba(255, 255, 255, 0.2);
    border-radius: 999px;
    font-weight: 700;
    letter-spacing: 0.025em;
    text-decoration: none;
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

/* Shimmer effect on button hover */
.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: left 0.5s;
}

.btn:hover::before {
    left: 100%;
}

.btn:hover,
.btn:focus {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 15px 40px rgba(56, 189, 248, 0.5), 
                0 6px 15px rgba(0, 0, 0, 0.3),
                inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.btn:active {
    transform: translateY(-1px) scale(0.98);
    transition: all 0.1s ease;
}

.btn--ghost {
    background: transparent;
    color: var(--color-muted);
    border: 1px solid var(--color-border);
}

.btn--ghost:hover,
.btn--ghost:focus {
    color: var(--color-text);
    border-color: var(--color-accent);
}

.section-heading h2 {
    margin-bottom: 0.4rem;
    font-size: clamp(1.75rem, 1.5vw + 1.5rem, 2.2rem);
}

.section-heading p {
    margin-top: 0;
    color: var(--color-muted);
    max-width: 60ch;
}

section {
    padding: 4rem 0;
}

.calc-form {
    display: grid;
    gap: 2rem;
}

fieldset {
    border: 1px solid var(--color-border);
    background: rgba(17, 28, 52, 0.65);
    border-radius: 1rem;
    padding: 1.5rem;
}

legend {
    padding: 0 0.5rem;
    font-weight: 600;
}

.field-group {
    display: grid;
    gap: 0.4rem;
    margin-bottom: 1.2rem;
}

label {
    font-size: 0.9rem;
    color: var(--color-muted);
}

input,
select {
    padding: 0.65rem 0.75rem;
    border-radius: 0.6rem;
    border: 1px solid transparent;
    background: rgba(15, 23, 42, 0.6);
    color: var(--color-text);
    font-size: 1rem;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input:focus,
select:focus {
    border-color: var(--color-accent);
    outline: none;
    box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.25);
}

input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.form-feedback {
    margin-top: 1.5rem;
    font-weight: 600;
    color: var(--color-accent);
}

.results {
    background: rgba(15, 23, 42, 0.45);
}

.results-grid {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.result-card {
    background: rgba(17, 28, 52, 0.75);
    border-radius: 1rem;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-soft);
    min-height: 190px;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.result-value {
    font-size: 1.75rem;
    font-weight: 700;
}

.result-note {
    color: var(--color-muted);
    margin-top: auto;
}

.result-card--list ul {
    padding-left: 1.1rem;
    margin: 0;
    display: grid;
    gap: 0.4rem;
}

.columns,
.guide-grid {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.comparison-list {
    list-style: none;
    padding: 0;
    display: grid;
    gap: 1rem;
}

.comparison-list li {
    padding: 1.25rem;
    background: rgba(17, 28, 52, 0.7);
    border-left: 4px solid var(--color-accent);
    border-radius: 0.8rem;
}

.faq details {
    background: rgba(17, 28, 52, 0.7);
    border-radius: 0.8rem;
    padding: 1rem 1.2rem;
    border: 1px solid var(--color-border);
    margin-bottom: 1rem;
}

.faq summary {
    cursor: pointer;
    font-weight: 600;
}

.faq p {
    margin: 0.5rem 0 0;
    color: var(--color-muted);
}

.cta {
    text-align: center;
}

.cta p {
    max-width: 50ch;
    margin: 0.75rem auto 2rem;
    color: var(--color-muted);
}

.site-footer {
    padding: 2.5rem 0;
    border-top: 1px solid var(--color-border);
    background: rgba(11, 18, 33, 0.95);
}

.site-footer .container {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: center;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--color-muted);
}

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

.site-footer a {
    color: var(--color-muted);
    text-decoration: none;
}

.site-footer a:hover,
.site-footer a:focus {
    color: var(--color-text);
}

.toast {
    position: fixed;
    inset: auto 1.5rem 1.5rem auto;
    background: rgba(15, 23, 42, 0.95);
    color: var(--color-text);
    padding: 0.9rem 1.4rem;
    border-radius: 0.75rem;
    border: 1px solid var(--color-accent);
    box-shadow: var(--shadow-soft);
    max-width: 320px;
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 720px) {
    .main-nav {
        gap: 1rem;
        font-size: 0.85rem;
    }

    fieldset {
        padding: 1.2rem;
    }

    .site-footer .container {
        flex-direction: column;
        align-items: flex-start;
    }
}

.form-feedback.error {
    color: #f87171;
}

.hero__support {
    color: var(--color-accent);
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.chart {
    background: rgba(10, 17, 31, 0.55);
}

.chart-wrapper {
    background: rgba(17, 28, 52, 0.7);
    border-radius: 1rem;
    padding: 1.75rem;
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-soft);
}

.chart-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

.chart-table th,
.chart-table td {
    padding: 0.85rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

.chart-table th {
    font-weight: 600;
    color: var(--color-text);
}

.chart-table tbody tr:nth-child(even) {
    background: rgba(15, 23, 42, 0.6);
}

.chart-note {
    margin: 0;
    color: var(--color-muted);
    font-size: 0.9rem;
}
.tools {
    background: rgba(13, 21, 38, 0.6);
}

.tool-grid {
    display: grid;
    gap: 2rem;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.tool-card {
    background: rgba(17, 28, 52, 0.75);
    border: 1px solid var(--color-border);
    border-radius: 1.1rem;
    padding: 1.8rem;
    box-shadow: var(--shadow-soft);
    display: grid;
    gap: 1.1rem;
}

.tool-intro {
    margin: 0;
    color: var(--color-muted);
}

.tool-form {
    display: grid;
    gap: 1rem;
}

.field-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 0.75rem;
}

.tool-selects {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 0.75rem;
}

.tool-form label {
    display: grid;
    gap: 0.4rem;
    font-size: 0.9rem;
    color: var(--color-muted);
}

.tool-form input,
.tool-form select {
    background: rgba(9, 15, 28, 0.9);
    border-radius: 0.6rem;
    padding: 0.6rem 0.75rem;
    border: 1px solid var(--color-border);
    color: var(--color-text);
}

.tool-form input:focus,
.tool-form select:focus {
    border-color: var(--color-accent);
    outline: none;
    box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.25);
}

.tool-output {
    border-top: 1px solid var(--color-border);
    padding-top: 0.9rem;
    color: var(--color-muted);
    font-size: 0.95rem;
    min-height: 2.2rem;
}

.tool-output strong {
    color: var(--color-text);
}

.how-to {
    background: rgba(15, 23, 42, 0.45);
}

.howto-steps {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 1.2rem;
}

.howto-steps h3 {
    margin: 0 0 0.35rem;
}

.howto-steps p {
    margin: 0;
    color: var(--color-muted);
}

.howto-tip {
    margin-top: 2rem;
    padding: 1.2rem 1.4rem;
    border-left: 4px solid var(--color-accent);
    border-radius: 0.9rem;
    background: rgba(17, 28, 52, 0.7);
    color: var(--color-text);
}

.link-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    color: var(--color-accent);
    font-weight: 600;
    text-decoration: none;
}

.link-btn:hover,
.link-btn:focus {
    color: var(--color-accent-dark);
    text-decoration: underline;
}

/* Guide and Blog Grid Styles */
.guide-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.guide-card {
    background: rgba(30, 41, 59, 0.5);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: 1rem;
    padding: 2rem;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.guide-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(56, 189, 248, 0.2);
    border-color: rgba(56, 189, 248, 0.5);
}

.guide-card h2 {
    margin-top: 0.5rem;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.guide-card h2 a {
    color: #f1f5f9;
    text-decoration: none;
    transition: color 0.3s;
}

.guide-card h2 a:hover {
    color: #38bdf8;
}

.guide-card p {
    color: #cbd5e1;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.guide-card .btn {
    display: inline-block;
    margin-top: 0.5rem;
}

@media (max-width: 720px) {
    .tool-grid {
        grid-template-columns: 1fr;
    }

    .field-grid,
    .tool-selects {
        grid-template-columns: 1fr;
    }
    
    .guide-grid {
        grid-template-columns: 1fr;
    }
}

/* ===================================================
   QUICK WIN 5: Background Patterns & Enhancements
   =================================================== */

/* Animated gradient orbs for depth */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(56, 189, 248, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(129, 140, 248, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 40% 20%, rgba(192, 132, 252, 0.05) 0%, transparent 40%);
    pointer-events: none;
    z-index: -1;
    animation: floatPattern 20s ease-in-out infinite;
}

@keyframes floatPattern {
    0%, 100% { transform: translate(0, 0); }
    33% { transform: translate(-10px, 10px); }
    66% { transform: translate(10px, -5px); }
}

/* Subtle grid overlay */
body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    z-index: -1;
}

/* Enhanced header with glass effect */
.site-header {
    background: rgba(15, 23, 42, 0.7);
    backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.2);
}

/* Scroll progress indicator */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, #38bdf8, #818cf8, #c084fc);
    z-index: 100;
    box-shadow: 0 0 10px rgba(56, 189, 248, 0.5);
}

/* Enhanced result cards with glassmorphism */
.result-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.result-card:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(56, 189, 248, 0.4);
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 15px 45px rgba(0, 0, 0, 0.4),
                0 0 30px rgba(56, 189, 248, 0.2);
}

/* Enhanced input fields with better focus states */
input:focus, select:focus {
    box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.25),
                0 4px 12px rgba(56, 189, 248, 0.2);
    transform: translateY(-2px);
}

/* Gradient result values */
.result-value {
    background: linear-gradient(135deg, var(--color-accent), #818cf8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Enhanced fieldsets */
fieldset {
    border: 1px solid rgba(255, 255, 255, 0.15);
    background: rgba(17, 28, 52, 0.4);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

fieldset:hover {
    border-color: rgba(56, 189, 248, 0.3);
    background: rgba(17, 28, 52, 0.5);
}

legend {
    color: var(--color-accent);
    font-weight: 700;
}
.guide-main {
    padding-top: 4rem;
    padding-bottom: 4rem;
}

.guide-hero {
    margin-bottom: 3rem;
    text-align: center;
}

.guide-hero h1 {
    font-size: clamp(2rem, 2vw + 1.5rem, 2.6rem);
    margin-bottom: 1rem;
}

.guide-content {
    background: rgba(17, 28, 52, 0.65);
    border-radius: 1.1rem;
    padding: 2.5rem;
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-soft);
    display: grid;
    gap: 1.75rem;
}

.guide-content h2 {
    margin-top: 0;
}

.guide-content table {
    width: 100%;
    border-collapse: collapse;
}

.guide-content table th,
.guide-content table td {
    padding: 0.8rem 1rem;
    border-bottom: 1px solid var(--color-border);
    text-align: left;
}

.guide-content ul,
.guide-content ol {
    margin: 0;
    padding-left: 1.2rem;
    display: grid;
    gap: 0.6rem;
}

.guide-content .actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.guide-content .btn[aria-disabled="true"] {
    pointer-events: none;
    opacity: 0.6;
}

@media (max-width: 720px) {
    .guide-content {
        padding: 1.8rem;
    }

    .guide-content .actions {
        flex-direction: column;
        align-items: stretch;
    }
}