/* ============================================================
   CalcSI — Design System (Stripe-inspired, Teal/Blue MD)
   ============================================================ */

/* --- Theme Variables --- */
:root {
    /* Primary — Teal */
    --color-primary:        var(--color-md-teal-600);   /* #00897B */
    --color-primary-deep:   var(--color-md-teal-700);   /* #00796B */
    --color-primary-press:  var(--color-md-teal-800);   /* #00695C */
    --color-primary-soft:   var(--color-md-teal-400);   /* #26A69A */
    --color-primary-bg:     var(--color-md-teal-50);    /* #E0F2F1 */

    /* Accent — Blue */
    --color-accent:         var(--color-md-blue-600);   /* #1E88E5 */
    --color-accent-deep:    var(--color-md-blue-700);   /* #1976D2 */

    /* Surfaces */
    --color-canvas:         #ffffff;
    --color-canvas-soft:    #f6f9fc;
    --color-canvas-warm:    var(--color-md-teal-50);
    --color-hairline:       #e3e8ee;
    --color-hairline-input: #a8c3de;

    /* Text — Blue Gray */
    --color-ink:            var(--color-md-bluegray-900);  /* #263238 */
    --color-ink-secondary:  var(--color-md-bluegray-800);  /* #37474F */
    --color-ink-mute:       var(--color-md-bluegray-400);  /* #78909C */
    --color-on-primary:     #ffffff;

    /* Semantic */
    --color-success:        var(--color-md-green-600);
    --color-warning:        var(--color-md-amber-600);
    --color-danger:         var(--color-md-red-600);
    --color-info:           var(--color-md-lightblue-600);

    /* Gradient Mesh Stops */
    --mesh-1: #e0f7fa;  /* cyan-50 */
    --mesh-2: #80cbc4;  /* teal-200 */
    --mesh-3: #4fc3f7;  /* lightblue-300 */
    --mesh-4: #00897B;  /* teal-600 */
    --mesh-5: #1565C0;  /* blue-800 */

    /* Spacing (8px base) */
    --sp-xxs: 2px;
    --sp-xs:  4px;
    --sp-sm:  8px;
    --sp-md:  12px;
    --sp-lg:  16px;
    --sp-xl:  24px;
    --sp-xxl: 32px;
    --sp-huge: 64px;

    /* Radii */
    --rounded-xs:   4px;
    --rounded-sm:   6px;
    --rounded-md:   8px;
    --rounded-lg:   12px;
    --rounded-xl:   16px;
    --rounded-pill: 9999px;

    /* Shadows */
    --shadow-1: 0 1px 3px rgba(0,55,112,.08);
    --shadow-2: 0 8px 24px rgba(0,55,112,.08), 0 2px 6px rgba(0,55,112,.04);
}

/* --- Base --- */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    font-weight: 300;
    font-feature-settings: "ss01";
    color: var(--color-ink);
    background: var(--color-canvas);
    line-height: 1.5;
    margin: 0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 300;
    color: var(--color-ink);
}

.display-hero {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 300;
    letter-spacing: -1.4px;
    line-height: 1.08;
}

.display-section {
    font-size: clamp(1.5rem, 3vw, 2.5rem);
    font-weight: 300;
    letter-spacing: -0.96px;
    line-height: 1.15;
}

.display-card {
    font-size: 1.5rem;
    font-weight: 300;
    letter-spacing: -0.64px;
    line-height: 1.1;
}

.text-muted-custom {
    color: var(--color-ink-mute) !important;
}

.text-primary {
    color: var(--color-primary) !important;
}

/* --- Gradient Mesh Hero --- */
.hero-mesh {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, var(--mesh-1) 0%, var(--mesh-2) 25%, var(--mesh-3) 50%, var(--mesh-4) 75%, var(--mesh-5) 100%);
    padding: 96px 0 80px;
}

.hero-mesh::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background:
        radial-gradient(ellipse 600px 400px at 20% 50%, rgba(178,235,242,.6), transparent),
        radial-gradient(ellipse 500px 350px at 60% 30%, rgba(77,195,172,.4), transparent),
        radial-gradient(ellipse 400px 300px at 80% 70%, rgba(21,101,192,.3), transparent);
    animation: meshFloat 20s ease-in-out infinite alternate;
    pointer-events: none;
}

@keyframes meshFloat {
    0%   { transform: translate(0, 0) rotate(0deg); }
    100% { transform: translate(-30px, 20px) rotate(2deg); }
}

.hero-mesh .container {
    position: relative;
    z-index: 1;
}

.hero-mesh h1 {
    color: var(--color-canvas);
    text-shadow: 0 1px 2px rgba(0,0,0,.15);
}

.hero-mesh p {
    color: rgba(255,255,255,.9);
}

/* --- Navbar --- */
.navbar-tools {
    background: rgba(255,255,255,.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-hairline);
    padding: var(--sp-md) 0;
    position: sticky;
    top: 0;
    z-index: 1030;
}

.navbar-tools .navbar-brand {
    font-weight: 400;
    font-size: 1.25rem;
    letter-spacing: -0.5px;
    color: var(--color-ink);
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
}

.navbar-tools .navbar-brand span {
    color: var(--color-primary);
}

.navbar-tools .navbar-logo {
    height: 28px;
    width: 28px;
    object-fit: contain;
    flex-shrink: 0;
}

.btn-lang-switch {
    background: transparent;
    border: 1px solid var(--color-hairline);
    color: var(--color-ink-mute);
    font-size: .85rem;
    padding: 4px 10px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    gap: 4px;
}
.btn-lang-switch:hover,
.btn-lang-switch:focus {
    border-color: var(--color-primary);
    color: var(--color-ink);
    background: var(--color-canvas-warm);
}
.btn-lang-switch img {
    border-radius: 2px;
    object-fit: cover;
}

/* --- Buttons --- */
.btn-primary {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-on-primary);
    font-weight: 400;
    font-size: 1rem;
    padding: var(--sp-sm) var(--sp-lg);
    transition: background-color .15s ease, transform .1s ease;
}

.btn-primary:hover,
.btn-primary:focus {
    background-color: var(--color-primary-deep);
    border-color: var(--color-primary-deep);
    color: var(--color-on-primary);
}

.btn-primary:active {
    background-color: var(--color-primary-press);
    border-color: var(--color-primary-press);
    transform: scale(.98);
}

.btn-outline-primary {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.btn-outline-primary:hover {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-on-primary);
}

.btn-pill {
    border-radius: var(--rounded-pill);
    padding: var(--sp-sm) var(--sp-xl);
}

.btn-sm.btn-pill {
    padding: var(--sp-xs) var(--sp-lg);
    font-size: .875rem;
}

/* --- Cards --- */
.card-tool {
    background: var(--color-canvas);
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-lg);
    padding: var(--sp-xl);
    transition: box-shadow .2s ease, transform .15s ease;
    text-decoration: none;
    color: inherit;
    display: block;
    height: 100%;
}

.card-tool:hover {
    box-shadow: var(--shadow-2);
    transform: translateY(-2px);
    text-decoration: none;
    color: inherit;
}

.card-tool .tool-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--rounded-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: var(--sp-lg);
}

.card-tool .tool-icon.teal {
    background: var(--color-md-teal-50);
    color: var(--color-md-teal-700);
}

.card-tool .tool-icon.blue {
    background: var(--color-md-blue-50);
    color: var(--color-md-blue-700);
}

.card-tool .tool-icon.cyan {
    background: var(--color-md-cyan-50);
    color: var(--color-md-cyan-700);
}

.card-tool .tool-icon.indigo {
    background: var(--color-md-indigo-50);
    color: var(--color-md-indigo-700);
}

.card-tool h3 {
    font-size: 1.125rem;
    font-weight: 400;
    letter-spacing: -0.22px;
    margin-bottom: var(--sp-sm);
}

.card-tool p {
    font-size: .9rem;
    color: var(--color-ink-mute);
    margin-bottom: 0;
    line-height: 1.5;
}

/* --- Tool Page Layout --- */
.tool-page {
    padding: var(--sp-huge) 0;
}

.tool-page .tool-container {
    max-width: 800px;
    margin: 0 auto;
}

.tool-workspace {
    background: var(--color-canvas);
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-lg);
    padding: var(--sp-xxl);
    box-shadow: var(--shadow-1);
}

.tool-workspace label {
    font-weight: 400;
    font-size: .9rem;
    color: var(--color-ink-secondary);
    margin-bottom: var(--sp-xs);
}

.tool-workspace .form-control,
.tool-workspace .form-select {
    border-color: var(--color-hairline-input);
    border-radius: var(--rounded-sm);
    padding: var(--sp-sm) var(--sp-md);
    font-size: .95rem;
    color: var(--color-ink);
    transition: border-color .15s ease;
}

.tool-workspace .form-control:focus,
.tool-workspace .form-select:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(0,137,123,.15);
}

/* Result display */
.result-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--sp-md);
    padding: var(--sp-md) var(--sp-lg);
    background: var(--color-canvas-soft);
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-sm);
    margin-bottom: var(--sp-sm);
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    font-size: .85rem;
    word-break: break-all;
}

.result-row .label {
    font-family: 'Inter', sans-serif;
    font-weight: 400;
    font-size: .8rem;
    color: var(--color-ink-mute);
    white-space: nowrap;
    min-width: 80px;
    font-feature-settings: "tnum";
}

.result-row .value {
    flex: 1;
    color: var(--color-ink);
    user-select: all;
}

.result-row .btn-copy {
    background: none;
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-xs);
    padding: var(--sp-xs) var(--sp-sm);
    color: var(--color-ink-mute);
    cursor: pointer;
    font-size: .75rem;
    white-space: nowrap;
    transition: all .15s ease;
}

.result-row .btn-copy:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.result-row .btn-copy.copied {
    border-color: var(--color-md-green-500);
    color: var(--color-md-green-700);
    background: var(--color-md-green-50);
}

/* --- SEO Content Section --- */
.seo-content {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--sp-huge) 0 var(--sp-xxl);
}

.seo-content h2 {
    font-size: 1.5rem;
    letter-spacing: -0.64px;
    margin-bottom: var(--sp-lg);
    margin-top: var(--sp-xxl);
}

.seo-content h2:first-child {
    margin-top: 0;
}

.seo-content p, .seo-content li {
    color: var(--color-ink-secondary);
    line-height: 1.7;
    font-size: .95rem;
}

/* --- Category Section --- */
.category-section {
    padding: var(--sp-huge) 0;
}

.category-section:nth-child(even) {
    background: var(--color-canvas-soft);
}

.category-badge {
    display: inline-block;
    background: var(--color-primary-bg);
    color: var(--color-primary-deep);
    font-size: .75rem;
    font-weight: 400;
    letter-spacing: 0.1px;
    text-transform: uppercase;
    padding: var(--sp-xs) var(--sp-sm);
    border-radius: var(--rounded-pill);
    margin-bottom: var(--sp-lg);
}

/* --- Search Bar --- */
.search-container {
    max-width: 560px;
    margin: 0 auto;
    position: relative;
}

.search-container .form-control {
    border-radius: var(--rounded-pill);
    padding: var(--sp-md) var(--sp-xl) var(--sp-md) 48px;
    border: 1px solid rgba(255,255,255,.3);
    background: rgba(255,255,255,.2);
    backdrop-filter: blur(8px);
    color: #fff;
    font-size: 1rem;
    font-weight: 300;
}

.search-container .form-control::placeholder {
    color: rgba(255,255,255,.6);
}

.search-container .form-control:focus {
    background: rgba(255,255,255,.95);
    color: var(--color-ink);
    border-color: transparent;
    box-shadow: var(--shadow-2);
}

.search-container .form-control:focus::placeholder {
    color: var(--color-ink-mute);
}

.search-container .search-icon {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: rgba(255,255,255,.6);
    pointer-events: none;
    transition: color .15s;
}

.search-container .form-control:focus ~ .search-icon {
    color: var(--color-ink-mute);
}

/* --- Footer --- */
.footer-tools {
    background: var(--color-canvas);
    border-top: 1px solid var(--color-hairline);
    padding: var(--sp-xxl) 0;
    color: var(--color-ink-mute);
    font-size: .85rem;
}

.footer-tools a {
    color: var(--color-ink-mute);
    text-decoration: none;
    transition: color .15s;
}

.footer-tools a:hover {
    color: var(--color-primary);
}

/* --- Live Ticker --- */
.live-ticker {
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 300;
    letter-spacing: -1px;
    color: var(--color-primary);
    font-feature-settings: "tnum";
    text-align: center;
    padding: var(--sp-xl) 0;
}

/* --- Breadcrumbs --- */
.breadcrumb-tools {
    padding: var(--sp-lg) 0;
    font-size: .85rem;
}

.breadcrumb-tools a {
    color: var(--color-ink-mute);
    text-decoration: none;
}

.breadcrumb-tools a:hover {
    color: var(--color-primary);
}

.breadcrumb-tools .separator {
    color: var(--color-ink-mute);
    margin: 0 var(--sp-sm);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .hero-mesh {
        padding: 64px 0 48px;
    }
    .tool-workspace {
        padding: var(--sp-xl);
    }
    .result-row {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--sp-xs);
    }
    .result-row .btn-copy {
        align-self: flex-end;
    }
    .category-section {
        padding: var(--sp-xxl) 0;
    }
}

@media (max-width: 576px) {
    .tool-workspace {
        padding: var(--sp-lg);
        border-radius: var(--rounded-md);
    }
    .btn-pill {
        padding: var(--sp-sm) var(--sp-lg);
    }
}