:root {
    --bg-main: #F8FAFC;
    --bg-card: #FFFFFF;
    --bg-sidebar: #FFFFFF;
    --border-color: #E2E8F0;
    --text-primary: #0F172A;
    --text-secondary: #64748B;
    --primary-color: #6366F1;
    --primary-hover: #4F46E5;
    --primary-light: #EEF2FF;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --radius-lg: 16px;
    --radius-md: 10px;
}

[data-theme="dark"] {
    --bg-main: #0B0F19;
    --bg-card: #1E293B;
    --bg-sidebar: #111827;
    --border-color: #334155;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --primary-color: #6366F1;
    --primary-hover: #818CF8;
    --primary-light: #1E1B4B;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    transition: background-color 0.3s ease;
}

.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 260px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    padding: 24px;
    position: fixed;
    height: 100vh;
    z-index: 10;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 32px;
}

.brand-icon {
    width: 36px;
    height: 36px;
    background-color: var(--primary-color);
    color: #fff;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.brand-name {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

.nav-menu {
    display: flex;
    flex-direction: column;
    gap: 6px;
    flex: 1;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 14px;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: 500;
    transition: all 0.2s ease;
}

.nav-item:hover, .nav-item.active {
    background-color: var(--primary-light);
    color: var(--primary-color);
}

.sidebar-footer {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.promo-card {
    background-color: var(--primary-light);
    padding: 16px;
    border-radius: var(--radius-md);
}

.promo-card h4 { font-size: 14px; margin-bottom: 4px; color: var(--text-primary); }
.promo-card p { font-size: 12px; color: var(--text-secondary); margin-bottom: 12px; }

.theme-switch-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 14px;
    color: var(--text-secondary);
}

/* Switch UI */
.switch { position: relative; display: inline-block; width: 44px; height: 24px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: #ccc; transition: .4s; border-radius: 24px; }
.slider:before { position: absolute; content: ""; height: 18px; width: 18px; left: 3px; bottom: 3px; background-color: white; transition: .4s; border-radius: 50%; }
input:checked + .slider { background-color: var(--primary-color); }
input:checked + .slider:before { transform: translateX(20px); }

/* Main Wrapper */
.main-wrapper {
    margin-left: 260px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.top-header {
    height: 70px;
    padding: 0 36px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-color: var(--bg-main);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 9;
}

.search-trigger {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 10px 16px;
    border-radius: 20px;
    width: 380px;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 14px;
}

.search-trigger kbd {
    margin-left: auto;
    background: var(--bg-main);
    padding: 2px 6px;
    border-radius: 4px;
    border: 1px solid var(--border-color);
    font-size: 11px;
}

.header-actions { display: flex; align-items: center; gap: 16px; }

/* Content Body */
.content-body { padding: 36px; max-width: 1200px; margin: 0 auto; width: 100%; }

/* Hero Section */
.hero-section {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    align-items: center;
    margin-bottom: 48px;
}

.hero-text h1 { font-size: 42px; font-weight: 800; line-height: 1.15; margin-bottom: 16px; }
.hero-subtitle { font-size: 16px; color: var(--text-secondary); margin-bottom: 24px; }

.hero-search-box {
    display: flex;
    align-items: center;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 30px;
    padding: 6px 8px 6px 18px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 16px;
}

.hero-search-box input {
    border: none;
    outline: none;
    background: transparent;
    flex: 1;
    padding: 8px;
    color: var(--text-primary);
}

.popular-searches { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 13px; color: var(--text-secondary); }
.search-chip {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 4px 12px;
    border-radius: 16px;
    color: var(--text-primary);
    text-decoration: none;
    transition: all 0.2s;
}
.search-chip:hover { border-color: var(--primary-color); color: var(--primary-color); }

/* Hero Graphic Visuals */
.hero-graphic { position: relative; height: 260px; display: flex; align-items: center; justify-content: center; }
.floating-card {
    background: var(--bg-card);
    padding: 20px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    width: 220px;
}
.payment-card .label { font-size: 12px; color: var(--text-secondary); }
.payment-card .amount { font-size: 22px; font-weight: 700; color: var(--primary-color); display: block; margin-top: 4px; }
.floating-badge {
    position: absolute;
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    box-shadow: var(--shadow-md);
}
.badge-calc { background: #8B5CF6; top: 20px; left: 20px; }
.badge-chart { background: #10B981; bottom: 30px; left: 40px; }
.badge-currency { background: #F59E0B; bottom: 40px; right: 30px; }

/* Grid Sections */
.section-container { margin-bottom: 48px; scroll-margin-top: 80px; }
.section-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.view-link { color: var(--primary-color); text-decoration: none; font-weight: 600; font-size: 14px; }

.categories-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 16px; }
.category-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 16px;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: transform 0.2s, box-shadow 0.2s;
}
.category-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }

.icon-wrapper {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}
.cat-finance { background: rgba(16,185,129,0.12); color: #10B981; }
.cat-health { background: rgba(236,72,153,0.12); color: #EC4899; }
.cat-business { background: rgba(139,92,246,0.12); color: #8B5CF6; }
.cat-education { background: rgba(59,130,246,0.12); color: #3B82F6; }
.cat-construction { background: rgba(249,115,22,0.12); color: #F97316; }
.cat-engineering { background: rgba(100,116,139,0.12); color: #64748B; }

.cat-details h3 { font-size: 14px; color: var(--text-primary); }
.cat-details p { font-size: 12px; color: var(--text-secondary); }

.tools-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 20px; }
.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    text-decoration: none;
    display: flex;
    flex-direction: column;
    transition: all 0.2s;
}
.tool-card:hover { border-color: var(--primary-color); transform: translateY(-2px); }
.tool-icon {
    width: 38px;
    height: 38px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 12px;
}
.icon-home { background: rgba(79,70,229,0.12); color: #4F46E5; }
.icon-health { background: rgba(236,72,153,0.12); color: #EC4899; }
.icon-math { background: rgba(139,92,246,0.12); color: #8B5CF6; }
.icon-finance { background: rgba(16,185,129,0.12); color: #10B981; }
.icon-chart { background: rgba(249,115,22,0.12); color: #F97316; }

.tool-card h3 { font-size: 15px; color: var(--text-primary); margin-bottom: 6px; }
.tool-card p { font-size: 12px; color: var(--text-secondary); line-height: 1.4; margin-bottom: 16px; flex: 1; }

.tag { display: inline-block; font-size: 11px; font-weight: 600; padding: 2px 8px; border-radius: 4px; width: fit-content; }
.tag-finance { background: rgba(16,185,129,0.12); color: #10B981; }
.tag-health { background: rgba(236,72,153,0.12); color: #EC4899; }
.tag-math { background: rgba(139,92,246,0.12); color: #8B5CF6; }

/* Why Us */
.why-us-banner {
    background: var(--primary-light);
    border-radius: var(--radius-lg);
    padding: 32px;
}
.why-us-banner h3 { font-size: 20px; margin-bottom: 24px; text-align: center; }
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 24px; }
.feature-item { display: flex; gap: 12px; }
.feature-icon {
    width: 36px;
    height: 36px;
    background: #fff;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
    flex-shrink: 0;
}
.feature-item h4 { font-size: 14px; margin-bottom: 2px; }
.feature-item p { font-size: 12px; color: var(--text-secondary); }

/* Buttons */
.btn {
    padding: 8px 16px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    border: none;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.2s;
}
.btn-primary { background-color: var(--primary-color); color: #fff; }
.btn-primary:hover { background-color: var(--primary-hover); }
.btn-outline { background: transparent; border: 1px solid var(--border-color); color: var(--text-primary); }
.btn-pill { border-radius: 20px; }
.btn-sm { padding: 6px 12px; font-size: 12px; }
.btn-full { width: 100%; }
.icon-btn { background: none; border: none; color: var(--text-secondary); font-size: 18px; cursor: pointer; }
.icon-btn .fa-sun { color: #F59E0B; }

/* Tool Page Layout */
.tool-runner-card { background: var(--bg-card); border-radius: var(--radius-lg); padding: 32px; border: 1px solid var(--border-color); }
.tool-header { margin-bottom: 24px; border-bottom: 1px solid var(--border-color); padding-bottom: 16px; }
.tool-grid-workspace { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.form-group { margin-bottom: 16px; display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 13px; font-weight: 600; }
.form-group input, .form-group select {
    padding: 10px;
    font-size: 14px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    background: var(--bg-main);
    color: var(--text-primary);
}
.calculator-results-card {
    background: var(--bg-main);
    border-radius: var(--radius-md);
    padding: 24px;
    border: 1px solid var(--border-color);
}
.result-stat-box { margin-top: 16px; }
.result-stat-box .res-label { font-size: 14px; color: var(--text-secondary); display: block; margin-bottom: 4px; }
.result-stat-box .res-val { font-size: 24px; font-weight: 700; color: var(--text-primary); }
.result-stat-box .res-val.highlight { font-size: 32px; color: var(--primary-color); }
.chart-container { height: 200px; margin-top: 24px; }
.result-table-container { margin-top: 32px; }
.result-table-container h4 { margin-bottom: 12px; }
.table-wrapper { max-height: 400px; overflow-y: auto; border: 1px solid var(--border-color); border-radius: var(--radius-md); }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 10px 14px; text-align: left; font-size: 13px; border-bottom: 1px solid var(--border-color); }
thead th { background: var(--bg-main); position: sticky; top: 0; }
tbody tr:last-child td { border-bottom: none; }

.bmi-gauge-container { display: flex; justify-content: center; margin-bottom: 20px; }
.bmi-gauge { width: 180px; height: 90px; position: relative; overflow: hidden; }
.bmi-gauge-fill {
    position: absolute;
    top: 0; left: 0; width: 180px; height: 180px;
    border-radius: 50%;
    background: #ccc;
    transform-origin: center center;
    transition: transform 0.5s;
}
.bmi-gauge-cover {
    width: 140px; height: 70px;
    background: var(--bg-main);
    position: absolute;
    top: 20px; left: 20px;
    border-top-left-radius: 70px;
    border-top-right-radius: 70px;
    display: flex; flex-direction: column; align-items: center; justify-content: flex-end; padding-bottom: 8px;
}
.bmi-value { font-size: 24px; font-weight: 700; }
.bmi-label { font-size: 12px; font-weight: 600; }
/* Add this for new date input fields */
.form-group input[type="date"] {
    -webkit-appearance: none;
}

/* Auth Layout */
.auth-page-body { display: flex; align-items: center; justify-content: center; min-height: 100vh; background: var(--bg-main); }
.auth-card { background: var(--bg-card); padding: 36px; border-radius: var(--radius-lg); border: 1px solid var(--border-color); width: 100%; max-width: 400px; }
.brand-center { justify-content: center; }
.auth-tabs { display: flex; margin-bottom: 20px; border-bottom: 1px solid var(--border-color); }
.auth-tab { flex: 1; padding: 10px; border: none; background: none; color: var(--text-secondary); cursor: pointer; font-weight: 600; }
.auth-tab.active { color: var(--primary-color); border-bottom: 2px solid var(--primary-color); }
.error-banner { background: #FEE2E2; color: #DC2626; padding: 10px; border-radius: 6px; font-size: 12px; margin-top: 10px; }
.success-banner { background: #D1FAE5; color: #059669; padding: 10px; border-radius: 6px; font-size: 12px; margin-top: 10px; }
.hidden { display: none !important; }
.mt-4 { margin-top: 16px; }

/* Modal */
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 100; display: flex; align-items: flex-start; justify-content: center; padding-top: 80px; }
.modal-card { background: var(--bg-card); width: 90%; max-width: 550px; border-radius: var(--radius-md); overflow: hidden; }
.modal-search-input-wrap { display: flex; align-items: center; padding: 16px; border-bottom: 1px solid var(--border-color); gap: 12px; }
.modal-search-input-wrap input { border: none; outline: none; flex: 1; font-size: 16px; background: transparent; color: var(--text-primary); }
.close-btn { background: none; border: none; font-size: 20px; cursor: pointer; color: var(--text-secondary); }
.search-results-list { max-height: 300px; overflow-y: auto; }
.search-item { padding: 12px 16px; display: block; text-decoration: none; color: var(--text-primary); border-bottom: 1px solid var(--border-color); }
.search-item:hover { background: var(--primary-light); }

/* Tool Not Found */
.tool-not-found {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 80px 24px;
    gap: 16px;
}
.not-found-icon {
    width: 64px;
    height: 64px;
    background: rgba(249,115,22,0.12);
    color: #F97316;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
}
.tool-not-found h2 { font-size: 24px; color: var(--text-primary); }
.tool-not-found p { font-size: 15px; color: var(--text-secondary); max-width: 380px; }

/* Footer */
.site-footer {
    background: var(--bg-sidebar);
    border-top: 1px solid var(--border-color);
    margin-left: 260px;
    padding: 32px 36px;
}
.footer-inner { max-width: 1200px; margin: 0 auto; display: flex; flex-direction: column; align-items: center; gap: 12px; text-align: center; }
.footer-brand { display: flex; align-items: center; gap: 10px; }
.footer-tagline { font-size: 13px; color: var(--text-secondary); }
.footer-links { display: flex; gap: 20px; flex-wrap: wrap; justify-content: center; }
.footer-links a { font-size: 13px; color: var(--text-secondary); text-decoration: none; transition: color 0.2s; }
.footer-links a:hover { color: var(--primary-color); }
.footer-copy { font-size: 12px; color: var(--text-secondary); }

/* Hamburger */
.hamburger-btn { display: none; background: none; border: none; font-size: 20px; color: var(--text-primary); cursor: pointer; padding: 4px 8px; }

/* Mobile sidebar overlay */
.sidebar-overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 9; }
.sidebar-overlay.active { display: block; }

/* Input focus ring */
.form-group input:focus, .form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99,102,241,0.15);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar { transform: translateX(-100%); transition: transform 0.3s ease; }
    .sidebar.open { transform: translateX(0); }
    .main-wrapper { margin-left: 0; }
    .site-footer { margin-left: 0; }
    .top-header { padding: 0 16px; }
    .hero-section { grid-template-columns: 1fr; }
    .hero-graphic { display: none; }
    .tool-grid-workspace { grid-template-columns: 1fr; }
    .hamburger-btn { display: block; }
    .search-trigger { width: auto; flex: 1; }
}

/* ── Auth Page ───────────────────────────────────────────── */
.auth-title    { font-size: 22px; font-weight: 700; margin-bottom: 4px; }
.auth-subtitle { font-size: 14px; color: var(--text-secondary); margin-bottom: 20px; }

.btn-google {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-weight: 600;
    font-size: 14px;
    gap: 10px;
    padding: 10px 16px;
}
.btn-google:hover { border-color: var(--primary-color); }

.auth-divider {
    display: flex;
    align-items: center;
    gap: 12px;
    margin: 16px 0;
    color: var(--text-secondary);
    font-size: 12px;
}
.auth-divider::before,
.auth-divider::after { content: ''; flex: 1; height: 1px; background: var(--border-color); }

.auth-banner {
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 13px;
    margin-top: 10px;
}
.auth-banner-error   { background: rgba(239,68,68,0.1);  color: #EF4444; }
.auth-banner-success { background: rgba(16,185,129,0.1); color: #10B981; }

.auth-switch-text {
    text-align: center;
    font-size: 13px;
    color: var(--text-secondary);
    margin-top: 16px;
}
.auth-switch-text a { color: var(--primary-color); text-decoration: none; font-weight: 600; }

.pw-toggle {
    position: absolute;
    right: 10px;
    bottom: 10px;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 14px;
}

.password-strength {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: 6px;
}
.strength-bar  { flex: 1; height: 4px; background: var(--border-color); border-radius: 4px; overflow: hidden; }
.strength-fill { height: 100%; border-radius: 4px; transition: width 0.3s, background 0.3s; }
.strength-label { font-size: 12px; font-weight: 600; min-width: 44px; }

/* ── Auth Header Slot ────────────────────────────────────── */
.auth-user-menu {
    display: flex;
    align-items: center;
    gap: 12px;
}
.auth-user-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    max-width: 120px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* ── Save Result Bar ─────────────────────────────────────── */
.save-result-bar {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-top: 24px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}
.save-result-msg {
    font-size: 13px;
    font-weight: 600;
}

/* ── History Page ────────────────────────────────────────── */
.history-state {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 80px 0;
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 24px;
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.history-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    transition: border-color 0.2s;
}
.history-card:hover { border-color: var(--primary-color); }

.history-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
    flex-wrap: wrap;
    gap: 8px;
}

.history-tool-name {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-primary);
    display: block;
}
.history-date {
    font-size: 12px;
    color: var(--text-secondary);
    display: block;
    margin-top: 2px;
}

.history-inputs {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 12px;
}
.history-input-chip {
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 3px 10px;
    font-size: 12px;
    color: var(--text-secondary);
}

.history-results {
    display: flex;
    flex-direction: column;
    gap: 4px;
    border-top: 1px solid var(--border-color);
    padding-top: 10px;
}
.history-result-line {
    display: flex;
    justify-content: space-between;
    font-size: 13px;
    color: var(--text-secondary);
}
.history-result-line strong { color: var(--text-primary); }

/* ── Responsive tweaks ───────────────────────────────────── */
@media (max-width: 768px) {
    .history-header { flex-direction: column; gap: 12px; }
    .auth-user-name { display: none; }
    .save-result-bar { flex-wrap: wrap; }
}

/* ── Input Validation ────────────────────────────────────── */
.form-group input.input-error,
.form-group select.input-error {
    border-color: #EF4444;
    box-shadow: 0 0 0 3px rgba(239,68,68,0.12);
}
.field-error {
    font-size: 12px;
    color: #EF4444;
    margin-top: 2px;
}

/* ── Copy Results Button ─────────────────────────────────── */
.copy-results-btn {
    transition: color 0.2s, border-color 0.2s;
}