:root {
    --bg-main: #f8fafc;
    --app-bg: #f8fafc;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --brand-green: #10b981;
    --brand-green-dark: #059669;
    --brand-red: #ef4444;
    --shadow-soft: 0 10px 25px -5px rgba(0,0,0,0.05), 0 8px 10px -6px rgba(0,0,0,0.01);
    --shadow-glow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Inter', -apple-system, sans-serif; background-color: #e2e8f0; color: var(--text-primary); height: 100vh; overflow: hidden; }

.presentation-layout { display: flex; height: 100%; align-items: center; justify-content: center; padding: 2rem; gap: 4rem; }

.back-home { position: absolute; top: 2rem; left: 2rem; color: var(--text-secondary); text-decoration: none; font-weight: 600; font-size: 0.95rem; }
.back-home:hover { color: var(--text-primary); }

/* Flat Mobile Frame */
.mobile-frame-container { display: flex; justify-content: center; align-items: center; }

.mobile-frame {
    width: 375px; height: 812px; background-color: var(--app-bg);
    border-radius: 40px; border: 12px solid #ffffff;
    box-shadow: 0 30px 60px -12px rgba(0,0,0,0.15), 0 0 0 1px rgba(0,0,0,0.05);
    position: relative; overflow: hidden; display: flex; flex-direction: column;
}

.app-header { 
    background: rgba(255,255,255,0.85); 
    backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0,0,0,0.05); 
    z-index: 100; position: sticky; top: 0; 
}
.status-bar { display: flex; justify-content: space-between; align-items: center; padding: 16px 24px; font-size: 0.95rem; font-weight: 700; color: var(--text-primary); }

.lang-toggle { cursor: pointer; background: #f1f5f9; padding: 6px 14px; border-radius: 20px; font-size: 0.75rem; color: var(--text-secondary); transition: all 0.2s;}
.lang-toggle:active { transform: scale(0.95); }
.lang-toggle span.active { font-weight: 800; color: var(--brand-green); }

.app-content { flex: 1; position: relative; overflow-y: auto; background: var(--app-bg); }

.screen {
    width: 100%; min-height: 100%;
    padding: 24px; padding-bottom: 80px;
    background: var(--app-bg);
    display: none; flex-direction: column;
    animation: fadeIn 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.screen.active { display: flex; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(15px); } to { opacity: 1; transform: translateY(0); } }

/* Controller */
.presentation-controller { width: 350px; background: white; border: none; border-radius: 24px; padding: 2.5rem; max-height: 812px; overflow-y: auto; box-shadow: var(--shadow-soft); }
.presentation-controller h2 { font-size: 1.5rem; margin-bottom: 0.5rem; color: var(--text-primary); font-weight: 800; letter-spacing: -0.5px; }
.presentation-controller p { color: var(--text-secondary); margin-bottom: 2rem; font-size: 0.9rem; font-weight: 500; }

.nav-buttons { display: flex; flex-direction: column; gap: 0.75rem; }
.nav-buttons button { background: #f8fafc; color: var(--text-primary); border: 2px solid transparent; padding: 1rem 1.2rem; border-radius: 16px; font-size: 0.95rem; cursor: pointer; text-align: left; font-family: inherit; font-weight: 600; transition: all 0.2s; }
.nav-buttons button:hover { background: #f1f5f9; }
.nav-buttons button.active { background: white; border-color: var(--brand-green); color: var(--brand-green-dark); box-shadow: 0 4px 12px rgba(16, 185, 129, 0.1); }

.simulation-events { margin-top: 2rem; border-top: 1px solid var(--border-color); padding-top: 1.5rem; }
.simulation-events h3 { font-size: 0.8rem; color: var(--text-secondary); margin-bottom: 1rem; font-weight: 800; text-transform: uppercase; letter-spacing: 1px; }
.sim-btn { background: white; border: 1px solid var(--border-color); color: var(--text-primary); padding: 1rem; width: 100%; border-radius: 16px; margin-bottom: 0.75rem; cursor: pointer; font-family: inherit; font-size: 0.9rem; font-weight: 600; transition: all 0.2s; box-shadow: 0 2px 5px rgba(0,0,0,0.02); }
.sim-btn:hover { border-color: #cbd5e1; transform: translateY(-1px); box-shadow: 0 4px 10px rgba(0,0,0,0.05); }
.sim-btn:active { transform: translateY(0); }

/* App UI Elements */
.app-title { font-size: 1.7rem; font-weight: 800; margin-bottom: 1.5rem; color: var(--text-primary); letter-spacing: -0.5px; }

.card { background: white; border: none; border-radius: 20px; padding: 24px; margin-bottom: 16px; box-shadow: var(--shadow-soft); transition: transform 0.2s, box-shadow 0.2s; }
.card.interactive { cursor: pointer; }
.card.interactive:hover { transform: translateY(-2px); box-shadow: 0 15px 30px -5px rgba(0,0,0,0.08); }
.card.interactive:active { transform: translateY(0); box-shadow: var(--shadow-soft); }
.card.highlight { border: 2px solid var(--brand-green); background: #f0fdf4; }

.input-group { margin-bottom: 1.2rem; }
.input-group input, .input-group select { width: 100%; padding: 1.2rem; border: 2px solid transparent; background: #f1f5f9; border-radius: 16px; font-size: 1.05rem; font-weight: 600; outline: none; font-family: inherit; transition: all 0.2s; color: var(--text-primary); }
.input-group input:focus { background: white; border-color: var(--brand-green); box-shadow: var(--shadow-glow); }

.btn-primary { width: 100%; padding: 1.2rem; background: linear-gradient(135deg, var(--brand-green), var(--brand-green-dark)); color: white; border: none; border-radius: 16px; font-size: 1.1rem; font-weight: 700; cursor: pointer; font-family: inherit; transition: all 0.2s; box-shadow: var(--shadow-glow); }
.btn-primary:hover { filter: brightness(1.1); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(1px); filter: brightness(0.9); box-shadow: 0 2px 5px rgba(16, 185, 129, 0.3); }

.btn-secondary { width: 100%; padding: 1.2rem; background: white; color: var(--text-primary); border: 2px solid #e2e8f0; border-radius: 16px; font-size: 1.1rem; font-weight: 700; cursor: pointer; margin-top: 12px; font-family: inherit; transition: all 0.2s; }
.btn-secondary:hover { border-color: #cbd5e1; background: #f8fafc; }
.btn-secondary:active { transform: translateY(1px); }

.badge { display: inline-block; padding: 6px 12px; border-radius: 8px; font-size: 0.75rem; font-weight: 800; text-transform: uppercase; letter-spacing: 0.5px; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.text-center { text-align: center; }

.toast { position: absolute; top: 80px; left: 50%; transform: translateX(-50%); background: #0f172a; color: white; padding: 14px 28px; border-radius: 12px; font-size: 0.95rem; display: none; z-index: 1000; font-weight: 600; box-shadow: 0 15px 30px rgba(0,0,0,0.2); animation: popDown 0.3s cubic-bezier(0.16, 1, 0.3, 1); }
@keyframes popDown { from { opacity: 0; transform: translate(-50%, -20px) scale(0.95); } to { opacity: 1; transform: translate(-50%, 0) scale(1); } }