/* =============================================================================
   StudyAI — identidade visual portada do MVP (studyai_br_mvp.html)
   Fontes: Syne (títulos) + DM Sans (texto). Paleta escura.
   ============================================================================= */
*{box-sizing:border-box;margin:0;padding:0}
:root{
--bg:#0a0a0f;
--bg2:#111118;
--bg3:#1a1a24;
--bg4:#22222e;
--surface:#1e1e2a;
--surface2:#252533;
--border:#2e2e3e;
--border2:#3a3a50;
--text:#f0f0f8;
--text2:#9090b0;
--text3:#5a5a78;
--accent:#6c63ff;
--accent2:#8b82ff;
--accent-glow:rgba(108,99,255,0.15);
--green:#22c55e;
--green-bg:rgba(34,197,94,0.1);
--amber:#f59e0b;
--amber-bg:rgba(245,158,11,0.1);
--red:#ef4444;
--red-bg:rgba(239,68,68,0.1);
--blue:#3b82f6;
--blue-bg:rgba(59,130,246,0.1);
--r:12px;
--r2:8px;
--r3:20px;
}
body{font-family:'DM Sans',sans-serif;background:var(--bg);color:var(--text);min-height:100vh;overflow-x:hidden}
h1,h2,h3,h4{font-family:'Syne',sans-serif}
a{color:inherit;text-decoration:none}

/* GRAIN OVERLAY */
body::before{content:'';position:fixed;inset:0;background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");pointer-events:none;z-index:1000;opacity:0.4}

/* SIDEBAR */
.sidebar{position:fixed;left:0;top:0;bottom:0;width:220px;background:var(--bg2);border-right:1px solid var(--border);display:flex;flex-direction:column;z-index:100}
.logo{padding:24px 20px 20px;border-bottom:1px solid var(--border)}
.logo-mark{font-family:'Syne',sans-serif;font-size:20px;font-weight:800;letter-spacing:-0.5px}
.logo-mark span{color:var(--accent)}
.logo-sub{font-size:11px;color:var(--text3);margin-top:2px;letter-spacing:0.05em;text-transform:uppercase}
nav{padding:16px 12px;flex:1}
.nav-section{font-size:10px;font-weight:600;letter-spacing:0.12em;text-transform:uppercase;color:var(--text3);padding:0 8px;margin-bottom:6px;margin-top:16px}
.nav-item{display:flex;align-items:center;gap:10px;padding:9px 10px;border-radius:var(--r2);cursor:pointer;font-size:13.5px;color:var(--text2);transition:all 0.15s;margin-bottom:2px;font-family:'DM Sans',sans-serif;font-weight:400}
.nav-item:hover{background:var(--bg3);color:var(--text)}
.nav-item.active{background:var(--accent-glow);color:var(--accent2);font-weight:500}
.nav-item svg{width:15px;height:15px;flex-shrink:0;opacity:0.8}
.nav-item.active svg{opacity:1}
.nav-item.disabled{opacity:0.5;cursor:not-allowed}
.nav-soon{font-size:9px;margin-left:auto;background:var(--bg4);color:var(--text3);padding:2px 6px;border-radius:10px;letter-spacing:0.04em}
.sidebar-footer{padding:16px 12px;border-top:1px solid var(--border)}
.plan-badge{background:var(--accent-glow);border:1px solid rgba(108,99,255,0.3);border-radius:var(--r2);padding:10px 12px}
.plan-name{font-size:11px;font-weight:600;color:var(--accent2);letter-spacing:0.05em;text-transform:uppercase}
.plan-limit{font-size:12px;color:var(--text3);margin-top:3px}
.logout-btn{margin-top:8px;width:100%;padding:7px;background:transparent;color:var(--text2);border:1px solid var(--border);border-radius:var(--r2);font-size:12px;font-weight:600;cursor:pointer;font-family:'Syne',sans-serif;transition:all 0.15s}
.logout-btn:hover{background:var(--bg3);color:var(--text)}

/* MAIN */
.main{margin-left:220px;min-height:100vh;padding:32px 36px}

/* PAGE HEADER */
.page-header{margin-bottom:32px}
.page-title{font-size:26px;font-weight:700;letter-spacing:-0.5px;margin-bottom:6px}
.page-desc{font-size:14px;color:var(--text2);line-height:1.6;max-width:520px}

/* CARDS */
.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:24px}
.card+.card{margin-top:16px}
.card-title{font-family:'Syne',sans-serif;font-size:14px;font-weight:600;margin-bottom:16px;color:var(--text);letter-spacing:0.02em}

/* GRID */
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.grid-3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:16px}

/* STAT CARDS */
.stat-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:20px;position:relative;overflow:hidden}
.stat-card::before{content:'';position:absolute;top:0;right:0;width:80px;height:80px;border-radius:50%;opacity:0.06;transform:translate(20px,-20px)}
.stat-card.flash::before{background:var(--accent)}
.stat-card.corr::before{background:var(--green)}
.stat-card.prev::before{background:var(--amber)}
.stat-label{font-size:11px;font-weight:500;color:var(--text3);text-transform:uppercase;letter-spacing:0.08em;margin-bottom:8px}
.stat-value{font-family:'Syne',sans-serif;font-size:28px;font-weight:700}
.stat-value.flash-col{color:var(--accent2)}
.stat-value.green-col{color:var(--green)}
.stat-value.amber-col{color:var(--amber)}
.stat-sub{font-size:12px;color:var(--text3);margin-top:4px}

/* INPUTS */
textarea,input,select{background:var(--bg3);border:1px solid var(--border);border-radius:var(--r2);color:var(--text);font-family:'DM Sans',sans-serif;font-size:14px;outline:none;transition:border-color 0.15s}
textarea{width:100%;padding:14px 16px;resize:vertical;min-height:120px;line-height:1.6}
input[type=text],input[type=number]{width:100%;padding:10px 14px;height:40px}
select{padding:8px 12px;height:38px;cursor:pointer;width:100%}
textarea:focus,input:focus,select:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-glow)}
::placeholder{color:var(--text3)}
label{font-size:12px;font-weight:500;color:var(--text2);display:block;margin-bottom:6px;letter-spacing:0.02em}
.form-group{margin-bottom:16px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:12px}

/* BUTTONS */
.btn{display:inline-flex;align-items:center;gap:8px;padding:10px 20px;border-radius:var(--r2);font-family:'Syne',sans-serif;font-size:13px;font-weight:600;cursor:pointer;border:none;transition:all 0.15s;letter-spacing:0.02em}
.btn:active{transform:scale(0.97)}
.btn-primary{background:var(--accent);color:#fff}
.btn-primary:hover{background:#7a72ff}
.btn-primary:disabled{background:var(--bg4);color:var(--text3);cursor:not-allowed;transform:none}
.btn-secondary{background:var(--bg3);color:var(--text2);border:1px solid var(--border)}
.btn-secondary:hover{background:var(--bg4);color:var(--text);border-color:var(--border2)}
.btn-sm{padding:7px 14px;font-size:12px}

/* TAGS / BADGES */
.badge{display:inline-flex;align-items:center;padding:3px 10px;border-radius:20px;font-size:11px;font-weight:600;letter-spacing:0.04em}
.badge-purple{background:var(--accent-glow);color:var(--accent2);border:1px solid rgba(108,99,255,0.3)}
.badge-green{background:var(--green-bg);color:var(--green);border:1px solid rgba(34,197,94,0.2)}
.badge-amber{background:var(--amber-bg);color:var(--amber);border:1px solid rgba(245,158,11,0.2)}

/* DIVIDER */
.divider{border:none;border-top:1px solid var(--border);margin:20px 0}

/* FLASHCARD AREA */
.flashcard-scene{perspective:1000px;width:100%;height:220px;cursor:pointer;margin:16px 0}
.flashcard{width:100%;height:100%;position:relative;transform-style:preserve-3d;transition:transform 0.5s cubic-bezier(0.4,0,0.2,1)}
.flashcard.flipped{transform:rotateY(180deg)}
.fc-face{position:absolute;inset:0;backface-visibility:hidden;background:var(--surface2);border:1px solid var(--border2);border-radius:var(--r);display:flex;flex-direction:column;align-items:center;justify-content:center;padding:28px;text-align:center}
.fc-face.back{transform:rotateY(180deg);background:var(--bg3)}
.fc-label{font-size:10px;font-weight:600;letter-spacing:0.1em;text-transform:uppercase;color:var(--text3);margin-bottom:12px}
.fc-text{font-size:16px;line-height:1.6;color:var(--text);font-family:'DM Sans',sans-serif}
.fc-back-text{font-size:14px;line-height:1.7;color:var(--text2)}
.fc-hint{font-size:11px;color:var(--text3);text-align:center;margin-top:-4px}

/* FLASHCARD NAV */
.fc-nav{display:flex;align-items:center;justify-content:space-between;margin-top:16px;gap:12px}
.fc-counter{font-size:13px;color:var(--text3);font-family:'Syne',sans-serif;font-weight:600;white-space:nowrap}
.fc-progress{flex:1;height:3px;background:var(--bg4);border-radius:4px;overflow:hidden}
.fc-progress-bar{height:100%;background:var(--accent);border-radius:4px;transition:width 0.3s}

/* DECK LIST */
.deck-item{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:18px 20px;display:flex;align-items:center;gap:16px;margin-bottom:10px;transition:border-color 0.15s}
.deck-item:hover{border-color:var(--border2)}
.deck-icon{width:40px;height:40px;background:var(--accent-glow);border-radius:var(--r2);display:flex;align-items:center;justify-content:center;flex-shrink:0;font-size:18px}
.deck-info{flex:1}
.deck-name{font-size:14px;font-weight:500;margin-bottom:3px;font-family:'Syne',sans-serif}
.deck-meta{font-size:12px;color:var(--text3)}
.deck-count{font-family:'Syne',sans-serif;font-size:20px;font-weight:700;color:var(--accent2)}

/* CHIP LIST */
.chips{display:flex;flex-wrap:wrap;gap:6px;margin-top:10px}
.chip{padding:5px 12px;background:var(--bg4);border:1px solid var(--border);border-radius:20px;font-size:12px;color:var(--text2);cursor:pointer;transition:all 0.15s}
.chip:hover,.chip.selected{background:var(--accent-glow);border-color:rgba(108,99,255,0.4);color:var(--accent2)}

/* LOADING */
.loading{display:flex;flex-direction:column;align-items:center;padding:48px;gap:16px}
.spinner{width:36px;height:36px;border:2px solid var(--border2);border-top-color:var(--accent);border-radius:50%;animation:spin 0.8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.loading-text{font-size:14px;color:var(--text2);font-family:'Syne',sans-serif}
/* Indicador HTMX: só aparece durante a requisição */
.htmx-indicator{display:none}
.htmx-request .htmx-indicator{display:flex}
.htmx-request.htmx-indicator{display:flex}

/* RESULT SECTION */
.result-section{animation:fadeUp 0.4s ease}
@keyframes fadeUp{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}

/* QUICK / MODULE CARDS */
.module-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:22px;transition:all 0.2s;display:block;position:relative}
.module-card.active-mod{cursor:pointer}
.module-card.active-mod:hover{border-color:var(--accent);transform:translateY(-2px);background:var(--surface2)}
.module-card.soon{opacity:0.65}
.module-icon{width:42px;height:42px;border-radius:var(--r2);display:flex;align-items:center;justify-content:center;margin-bottom:14px}
.module-label{font-family:'Syne',sans-serif;font-size:15px;font-weight:600;margin-bottom:6px;display:flex;align-items:center;gap:8px}
.module-desc{font-size:12.5px;color:var(--text3);line-height:1.55}

/* WELCOME BANNER */
.welcome-banner{background:linear-gradient(135deg,var(--surface) 0%,var(--bg3) 100%);border:1px solid var(--border);border-radius:var(--r);padding:28px 32px;margin-bottom:24px;position:relative;overflow:hidden}
.welcome-banner::after{content:'';position:absolute;top:-60px;right:-40px;width:200px;height:200px;background:var(--accent);opacity:0.04;border-radius:50%}
.welcome-name{font-family:'Syne',sans-serif;font-size:22px;font-weight:700;margin-bottom:6px}
.welcome-sub{font-size:14px;color:var(--text2);line-height:1.5}

/* SECTION TITLE */
.section-title{font-family:'Syne',sans-serif;font-size:13px;font-weight:600;color:var(--text3);text-transform:uppercase;letter-spacing:0.08em;margin-bottom:12px}

/* EMPTY STATE */
.empty{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:48px 32px;text-align:center;background:var(--surface);border:1px solid var(--border);border-radius:var(--r)}
.empty-icon{font-size:42px;margin-bottom:14px;opacity:0.4}
.empty-title{font-family:'Syne',sans-serif;font-size:16px;font-weight:600;margin-bottom:6px}
.empty-desc{font-size:13px;color:var(--text3);max-width:280px;line-height:1.6}

/* WORD COUNT */
.wc{font-size:11px;color:var(--text3);text-align:right;margin-top:4px}

/* ERROR */
.error-box{padding:28px;text-align:center}
.error-icon{font-size:32px;margin-bottom:12px}
.error-title{font-family:'Syne',sans-serif;font-size:14px;font-weight:600;margin-bottom:8px;color:var(--red)}
.error-text{font-size:13px;color:var(--text2);line-height:1.6}

/* PLACEHOLDER RESULT */
.placeholder-card{min-height:300px;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:10px}
.placeholder-emoji{font-size:40px;opacity:0.2}
.placeholder-text{font-size:14px;color:var(--text3);font-family:'Syne',sans-serif}

/* SCROLLBAR */
::-webkit-scrollbar{width:6px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:var(--border2);border-radius:4px}
::-webkit-scrollbar-thumb:hover{background:var(--text3)}

@media (max-width:760px){
  .sidebar{position:static;width:100%;height:auto}
  .main{margin-left:0;padding:20px}
  .grid-2,.grid-3{grid-template-columns:1fr}
}