/* ============================================================================
   SCAD → STL converter — styles
   Dark theme, mobile-first. Navbar chrome comes from /shared-topnav.css (.tt-scope);
   this file only seeds --tt-topnav-h (published live by tt-navbar.js) and themes
   the tool itself.
   ============================================================================ */
:root {
    /* Seed the shared navbar height (tt-navbar.js publishes the exact px at runtime) */
    --tt-topnav-h: 64px;

    --bg:        #07070b;
    --bg-2:      #0e0e15;
    --panel:     #14141d;
    --panel-2:   #1a1a26;
    --inset:     #0c0c13;
    --border:    rgba(255, 255, 255, 0.09);
    --border-2:  rgba(255, 255, 255, 0.15);

    --text:      #f3f4f8;
    --text-2:    rgba(243, 244, 248, 0.72);
    --text-3:    rgba(243, 244, 248, 0.46);

    --indigo:    #6366f1;
    --violet:    #8b5cf6;
    --cyan:      #06b6d4;
    --green:     #22c55e;
    --amber:     #f59e0b;
    --red:       #f87171;

    --grad:      linear-gradient(135deg, #818cf8 0%, #22d3ee 52%, #c084fc 100%);
    --grad-acc:  linear-gradient(135deg, var(--indigo), var(--violet));

    --r-sm: 8px;
    --r-md: 12px;
    --r-lg: 18px;

    --mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
    --shadow: 0 18px 50px -22px rgba(0, 0, 0, 0.75);
    --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background:
        radial-gradient(1100px 600px at 82% -8%, rgba(34, 211, 238, 0.10), transparent 60%),
        radial-gradient(900px 540px at 4% 0%, rgba(99, 102, 241, 0.13), transparent 58%),
        var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    overflow-x: clip; /* never break position:sticky on the navbar (navbar-v2 lesson) */
}

code { font-family: var(--mono); font-size: 0.9em; }

.page {
    max-width: 1240px;
    margin: 0 auto;
    padding: clamp(1rem, 3vw, 2rem) clamp(0.85rem, 3vw, 1.75rem) 2rem;
}

/* ----------------------------- Hero ----------------------------- */
.hero { text-align: center; padding: clamp(1.2rem, 4vw, 2.4rem) 0 clamp(1rem, 3vw, 1.6rem); }
.hero-eyebrow {
    display: inline-flex; align-items: center; gap: 0.5rem;
    font-size: 0.8rem; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase;
    color: var(--cyan);
    background: rgba(6, 182, 212, 0.1);
    border: 1px solid rgba(6, 182, 212, 0.22);
    padding: 0.32rem 0.8rem; border-radius: 999px;
}
.hero-title {
    margin: 0.9rem 0 0.5rem;
    font-size: clamp(1.7rem, 5vw, 2.9rem); font-weight: 800; letter-spacing: -0.02em;
    background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-sub {
    max-width: 660px; margin: 0 auto; color: var(--text-2);
    font-size: clamp(0.95rem, 2.4vw, 1.08rem);
}
.hero-sub code { color: var(--cyan); background: rgba(6,182,212,0.1); padding: 0.05em 0.35em; border-radius: 5px; }
.hero-sub strong { color: var(--text); }

/* ----------------------------- Workbench ----------------------------- */
.workbench {
    display: grid; grid-template-columns: 1fr; gap: clamp(0.85rem, 2vw, 1.25rem);
    align-items: start;
}
@media (min-width: 980px) {
    .workbench { grid-template-columns: minmax(340px, 0.92fr) 1.08fr; }
}

.panel {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: var(--r-lg);
    padding: clamp(0.85rem, 2vw, 1.15rem);
    box-shadow: var(--shadow);
}

/* ----------------------------- Segmented tabs ----------------------------- */
.seg {
    display: flex; gap: 0.3rem; padding: 0.3rem;
    background: var(--inset); border: 1px solid var(--border); border-radius: var(--r-md);
    margin-bottom: 0.9rem;
}
.seg-btn {
    flex: 1; display: inline-flex; align-items: center; justify-content: center; gap: 0.45rem;
    min-height: 44px; padding: 0.5rem 0.6rem;
    background: transparent; border: 0; border-radius: var(--r-sm);
    color: var(--text-2); font: inherit; font-weight: 600; font-size: 0.92rem; cursor: pointer;
    transition: background var(--ease) 0.2s, color var(--ease) 0.2s;
}
.seg-btn:hover { color: var(--text); }
.seg-btn.active { background: var(--panel-2); color: var(--text); box-shadow: inset 0 0 0 1px var(--border-2); }

.tab-pane.hidden, .hidden { display: none !important; }

/* ----------------------------- Editor ----------------------------- */
.editor-bar {
    display: flex; align-items: center; justify-content: space-between; gap: 0.6rem;
    margin-bottom: 0.55rem;
}
.field-inline {
    display: inline-flex; align-items: center; gap: 0.45rem;
    font-size: 0.82rem; color: var(--text-3); font-weight: 600;
}
.field-inline select { min-height: 38px; }
.editor-meta {
    font-family: var(--mono); font-size: 0.74rem; color: var(--text-3);
    background: var(--inset); border: 1px solid var(--border); border-radius: 999px;
    padding: 0.2rem 0.6rem;
}
.editor-meta::after { content: ' lines'; }

textarea.code {
    display: block; width: 100%; min-height: 300px; resize: vertical;
    background: var(--inset); color: #e7e9f3;
    border: 1px solid var(--border); border-radius: var(--r-md);
    padding: 0.85rem 0.95rem;
    font-family: var(--mono); font-size: 0.86rem; line-height: 1.6;
    tab-size: 2; white-space: pre; overflow: auto;
}
textarea.code:focus { outline: none; border-color: var(--indigo); box-shadow: 0 0 0 3px rgba(99,102,241,0.18); }

/* ----------------------------- Dropzone ----------------------------- */
.dropzone {
    display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center;
    min-height: 300px; gap: 0.4rem; padding: 1.2rem;
    background: var(--inset);
    border: 2px dashed var(--border-2); border-radius: var(--r-md);
    color: var(--text-2); cursor: pointer;
    transition: border-color var(--ease) 0.2s, background var(--ease) 0.2s, transform var(--ease) 0.15s;
}
.dropzone:hover, .dropzone:focus-visible { border-color: var(--indigo); background: rgba(99,102,241,0.06); outline: none; }
.dropzone.dragover { border-color: var(--cyan); background: rgba(6,182,212,0.08); transform: scale(1.005); }
.dropzone i { font-size: 2.4rem; color: var(--indigo); }
.dropzone h3 { margin: 0.3rem 0 0; font-size: 1.05rem; color: var(--text); font-weight: 700; }
.dropzone p { margin: 0; font-size: 0.85rem; color: var(--text-3); }
.dropzone code { color: var(--cyan); }
.upload-status { min-height: 1.2rem; margin: 0.55rem 2px 0; font-size: 0.84rem; color: var(--green); }
.upload-status.err { color: var(--red); }

/* ----------------------------- Options ----------------------------- */
.options {
    display: grid; grid-template-columns: 1fr 1fr; gap: 0.7rem;
    margin: 0.95rem 0 0.85rem;
}
.field { display: flex; flex-direction: column; gap: 0.32rem; font-size: 0.78rem; color: var(--text-3); font-weight: 600; }
.check {
    grid-column: 1 / -1; display: flex; align-items: center; gap: 0.55rem;
    font-size: 0.85rem; color: var(--text-2); cursor: pointer; min-height: 30px;
}
.check em { color: var(--amber); font-style: normal; font-weight: 600; }
.check input { width: 18px; height: 18px; accent-color: var(--indigo); cursor: pointer; }

select, input[type="number"] {
    width: 100%; min-height: 42px; padding: 0.5rem 0.6rem;
    background: var(--inset); color: var(--text);
    border: 1px solid var(--border); border-radius: var(--r-sm);
    font: inherit; font-size: 0.9rem;
}
select:focus, input[type="number"]:focus { outline: none; border-color: var(--indigo); box-shadow: 0 0 0 3px rgba(99,102,241,0.16); }
select option { background: var(--panel-2); }

/* ----------------------------- Convert button ----------------------------- */
.convert-btn {
    width: 100%; min-height: 52px; display: inline-flex; align-items: center; justify-content: center; gap: 0.6rem;
    background: var(--grad-acc); color: #fff; font: inherit; font-weight: 700; font-size: 1.02rem;
    border: 0; border-radius: var(--r-md); cursor: pointer;
    box-shadow: 0 10px 26px -10px rgba(99,102,241,0.7);
    transition: transform var(--ease) 0.15s, box-shadow var(--ease) 0.2s, filter var(--ease) 0.2s;
}
.convert-btn:hover { transform: translateY(-1px); filter: brightness(1.06); }
.convert-btn:active { transform: translateY(0); }
.convert-btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none; box-shadow: none; filter: grayscale(0.3); }
.convert-btn i { font-size: 0.95em; }

.privacy-note {
    display: flex; align-items: center; justify-content: center; gap: 0.45rem;
    margin: 0.7rem 0 0; font-size: 0.78rem; color: var(--text-3); text-align: center;
}
.privacy-note i { color: var(--green); }

/* ----------------------------- Viewer ----------------------------- */
.viewer-wrap {
    position: relative; overflow: hidden;
    height: clamp(340px, 50vh, 600px);
    background:
        radial-gradient(120% 120% at 50% 0%, rgba(99,102,241,0.10), transparent 60%),
        var(--inset);
    border: 1px solid var(--border); border-radius: var(--r-md);
}
.viewer { position: absolute; inset: 0; }
.viewer canvas { display: block; width: 100% !important; height: 100% !important; }

.viewer-empty, .viewer-busy {
    position: absolute; inset: 0;
    display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 0.5rem;
    text-align: center; padding: 1rem; pointer-events: none;
}
.viewer-empty i { font-size: 2.8rem; color: var(--text-3); opacity: 0.5; }
.viewer-empty p { margin: 0; font-weight: 600; color: var(--text-2); }
.viewer-empty-hint { font-size: 0.82rem; color: var(--text-3); }

.viewer-busy { background: rgba(7,7,11,0.62); backdrop-filter: blur(2px); }
.busy-status { margin: 0; font-weight: 600; color: var(--text); }
.busy-elapsed { font-family: var(--mono); font-size: 0.8rem; color: var(--cyan); }
.spinner {
    width: 46px; height: 46px; border-radius: 50%;
    border: 3px solid rgba(255,255,255,0.12); border-top-color: var(--cyan);
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.viewer-tools {
    position: absolute; top: 0.6rem; right: 0.6rem; display: flex; gap: 0.35rem;
}
.vtool {
    width: 40px; height: 40px; display: inline-flex; align-items: center; justify-content: center;
    background: rgba(20,20,29,0.82); color: var(--text-2);
    border: 1px solid var(--border-2); border-radius: var(--r-sm); cursor: pointer;
    transition: color var(--ease) 0.15s, background var(--ease) 0.15s;
    backdrop-filter: blur(4px);
}
.vtool:hover { color: var(--text); background: var(--panel-2); }
.vtool.active { color: var(--cyan); border-color: rgba(6,182,212,0.5); }

/* ----------------------------- Result / stats ----------------------------- */
.result { margin-top: 0.9rem; }
.stats {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.5rem; margin-bottom: 0.8rem;
}
.stat {
    background: var(--inset); border: 1px solid var(--border); border-radius: var(--r-sm);
    padding: 0.55rem 0.6rem; display: flex; flex-direction: column; gap: 0.15rem; min-width: 0;
}
.stat-label { font-size: 0.68rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--text-3); font-weight: 600; }
.stat-value { font-family: var(--mono); font-size: 0.92rem; color: var(--text); font-weight: 600; overflow-wrap: anywhere; }

.download-btn {
    width: 100%; min-height: 50px; display: inline-flex; align-items: center; justify-content: center; gap: 0.55rem;
    flex-wrap: wrap;
    background: var(--green); color: #04130a; font: inherit; font-weight: 700; font-size: 1rem;
    border: 0; border-radius: var(--r-md); cursor: pointer;
    transition: transform var(--ease) 0.15s, filter var(--ease) 0.2s;
}
.download-btn:hover { transform: translateY(-1px); filter: brightness(1.05); }
.download-name { font-family: var(--mono); font-size: 0.8rem; font-weight: 600; opacity: 0.78; }

/* ----------------------------- Error + log ----------------------------- */
.error-banner {
    display: flex; align-items: flex-start; gap: 0.6rem; margin-top: 0.85rem;
    background: rgba(248,113,113,0.1); border: 1px solid rgba(248,113,113,0.4); border-radius: var(--r-md);
    padding: 0.8rem 0.9rem; color: #fecaca; font-size: 0.88rem;
}
.error-banner i { color: var(--red); margin-top: 0.1rem; }

.logbox { margin-top: 0.85rem; border: 1px solid var(--border); border-radius: var(--r-md); background: var(--inset); overflow: hidden; }
.logbox summary {
    list-style: none; cursor: pointer; padding: 0.6rem 0.85rem;
    font-size: 0.84rem; font-weight: 600; color: var(--text-2); display: flex; align-items: center; gap: 0.5rem;
}
.logbox summary::-webkit-details-marker { display: none; }
.logbox summary i { color: var(--text-3); }
.logbox[open] summary { border-bottom: 1px solid var(--border); }
.log-output {
    margin: 0; max-height: 230px; overflow: auto; padding: 0.75rem 0.9rem;
    font-family: var(--mono); font-size: 0.76rem; line-height: 1.55; color: var(--text-2);
    white-space: pre-wrap; word-break: break-word;
}
.log-output .l-err { color: #fca5a5; }
.log-output .l-sys { color: var(--cyan); }
.log-output .l-out { color: var(--text-3); }

/* ----------------------------- About ----------------------------- */
.about { margin: clamp(1.6rem, 5vw, 3rem) 0 0; }
.about > h2 { text-align: center; font-size: clamp(1.2rem, 3vw, 1.6rem); font-weight: 800; margin: 0 0 1.1rem; }
.about-grid { display: grid; grid-template-columns: 1fr; gap: 0.85rem; }
@media (min-width: 740px) { .about-grid { grid-template-columns: repeat(3, 1fr); } }
.about-card {
    background: var(--panel); border: 1px solid var(--border); border-radius: var(--r-md); padding: 1.1rem;
}
.about-card i { font-size: 1.4rem; color: var(--indigo); }
.about-card h3 { margin: 0.6rem 0 0.35rem; font-size: 1.02rem; font-weight: 700; }
.about-card p { margin: 0; font-size: 0.88rem; color: var(--text-2); }
.about-card code { color: var(--cyan); }

/* ----------------------------- Footer ----------------------------- */
.foot {
    display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 0.6rem;
    margin-top: clamp(1.6rem, 5vw, 3rem); padding-top: 1.1rem; border-top: 1px solid var(--border);
    font-size: 0.82rem; color: var(--text-3);
}
.foot-home { color: var(--text-2); text-decoration: none; display: inline-flex; align-items: center; gap: 0.4rem; font-weight: 600; }
.foot-home:hover { color: var(--text); }
.foot-engine { font-family: var(--mono); font-size: 0.74rem; }

/* ----------------------------- Mobile ----------------------------- */
@media (max-width: 560px) {
    .options { grid-template-columns: 1fr; }
    .stats { grid-template-columns: repeat(2, 1fr); }
    .viewer-wrap { height: clamp(300px, 60vw, 360px); }
}
@media (max-width: 380px) {
    .seg-btn span { display: none; } /* icon-only tabs on the tightest phones */
}