*{
    margin:0;
    padding:0;
    box-sizing:border-box;
}

html{
    scroll-behavior:smooth;
}

body{
    font-family:Arial, Helvetica, sans-serif;
    background:#def7ff;
    min-height:100vh;
    overflow-x:hidden;
    color:#222;
}

/* ===========================
   NAVBAR
=========================== */

nav{
    width:100%;
    padding:0.75rem 2rem;
    display:flex;
    justify-content:space-between;
    align-items:center;
    background:#fff;
    border-bottom:1px solid rgba(0,0,0,.08);
    box-shadow:0 2px 8px rgba(0,0,0,.08);
    position:sticky;
    top:0;
    z-index:1000;
}

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

.brand img{
    width:55px;
    height:55px;
    display:block;
}

.brand h1{
    font-family:'Orbitron',sans-serif;
    font-size:clamp(1.4rem,2vw,1.8rem);
    letter-spacing:2px;
    margin:0;
}

.mech a{
    text-decoration:none;
    color:#012043;
}

.circuits a{
    text-decoration:none;
    color:#0057d9;
}

nav ul{
    display:flex;
    align-items:center;
    gap:2rem;
    list-style:none;
}

nav ul li a{
    text-decoration:none;
    color:#003db8;
    font-size:1.05rem;
    transition:.3s;
}

nav ul li a:hover{
    color:#00bcd4;
}

/* ===========================
   HAMBURGER MENU
=========================== */

.hamburger{
    display:none;
    flex-direction:column;
    gap:5px;
    cursor:pointer;
}

.hamburger span{
    width:28px;
    height:3px;
    background:#003366;
    border-radius:3px;
    transition:.3s;
}

/* ===========================
   CONTACT & FEEDBACK POPUPS
=========================== */

.contact-menu,
.feedback-menu{
    position:relative;
}

.contact-box,
.feedback-box{
    display:none;
    position:absolute;
    top:42px;
    right:0;
    width:320px;
    background:#fff;
    color:#012043;
    padding:18px;
    border-radius:12px;
    box-shadow:0 8px 25px rgba(0,0,0,.25);
    z-index:9999;
    animation:popup .2s ease;
}

@keyframes popup{
    from{
        opacity:0;
        transform:translateY(-8px);
    }
    to{
        opacity:1;
        transform:translateY(0);
    }
}

/* ===========================
   MOBILE
=========================== */

@media (max-width:600px){

    nav{
        display:flex;
        justify-content:space-between;
        align-items:center;
        flex-wrap:wrap;
        padding:15px 20px;
    }

    .brand{
        display:flex;
        align-items:center;
        gap:10px;
        flex:1;
    }

    .brand img{
        width:45px;
        height:45px;
    }

    .brand h1{
        font-size:28px;
        margin:0;
    }

    .hamburger{
        display:flex;
        flex-direction:column;
        gap:5px;
        cursor:pointer;
        margin-left:auto;
    }

    .hamburger span{
        width:28px;
        height:3px;
        background:#003366;
        border-radius:3px;
    }

    #nav-links{
        display:none;
        width:100%;
        flex-direction:column;
        margin-top:10px;
        gap:0;
        padding:0;
    }

    #nav-links.active{
        display:flex;
    }

    #nav-links li{
        width:100%;
        margin:0;
        padding:0;
        list-style:none;
        line-height:1;
    }

    #nav-links li a{
        display:block;
        padding:10px 15px;
        margin:0;
        text-align:center;
        line-height:1.2;
    }

    .contact-box,
    .feedback-box{
        position:fixed;
        top:90px;
        left:50%;
        right:auto;
        transform:translateX(-50%);
        width:320px;
        max-width:90%;
    }
}

/* ===========================
   EXTRA SMALL PHONES
=========================== */

@media (max-width:380px){

    nav{
        padding:.8rem;
    }

    .brand h1{
        font-size:1.2rem;
    }
}

/* ===========================
   GEAR GENERATOR
=========================== */

/* ===========================
   SIMULATOR LAYOUT
=========================== */

.simulator-layout{

    display:grid;

    grid-template-columns:280px minmax(0, 1fr);

    width:100%;

    height:calc(100vh - 70px);

    overflow:hidden;

}


/* ===========================
   SIDEBAR
=========================== */

.control-panel{

    width:100%;

    height:100%;

    overflow-y:auto;

    overflow-x:hidden;

    background:#ffffff;

    padding:20px;

    border-right:1px solid rgba(0,0,0,.15);

    box-shadow:2px 0 8px rgba(0,0,0,.08);

}

.intro-text{
    text-align:center;
}

.intro-text h1{
    font-family:'Orbitron',sans-serif;
    font-size:clamp(1.4rem, 2.5vw, 1.8rem);
    color:#012043;
    margin-bottom:10px;
}

.intro-text p{
    margin:1 auto;
    line-height:1.5;
    color:#333;
}


.add-gear-button{

    width:100%;

    padding:12px;

    border:none;

    border-radius:6px;

    background:#0057d9;

    color:white;

    font-size:1rem;

    font-weight:bold;

    cursor:pointer;

}


.add-gear-button:hover{

    background:#003db8;

}

.input-parameter-section{

    margin-top:20px;

}

.input-parameter-section h3{

    text-align:center;

    margin-bottom:20px;

}


.parameter-row{

    display:flex;

    align-items:center;

    margin-bottom:12px;

}


.parameter-row label{

    width:70px;

}


.parameter-row input{

    width:150px;

    padding:6px;

}


.parameter-row select{

    width:230px;

    height:40px;

    padding:6px 10px;

}


.section-title{

    font-size:14px;

    font-weight:bold;

    text-transform:uppercase;

    margin-bottom:10px;

}


.parameter-button{

    width:100%;

    padding:10px;

    border:none;

    background:none;

    text-align:left;

    cursor:pointer;

    font-size:14px;

}


.parameter-button:hover{

    background:#eeeeee;

}


.gear-dropdown{

    display:none;

    padding:5px 10px 10px 25px;

}


.gear-dropdown.active{

    display:block;

}


#gearParameterSelect{

    width:100%;

    padding:7px;

}

/* ===========================
   GEAR TRAIN BUTTONS
=========================== */

.gear-train-buttons{

    display:flex;

    gap:10px;

    margin-top:10px;

}


.gear-train-buttons button{

    flex:1;

    padding:11px;

    border:none;

    border-radius:6px;

    color:white;

    font-size:1rem;

    font-weight:bold;

    cursor:pointer;

}


/* ===========================
   RUN BUTTON
=========================== */

.run-gear-train-button{

    background:#0057d9;

}


.run-gear-train-button:hover{

    background:#003db8;

}


/* ===========================
   STOP BUTTON
=========================== */

.stop-gear-train-button{

    background:#dc3545;

}


.stop-gear-train-button:hover{

    background:#b02a37;

}

/* ===========================
   GEAR LIST
=========================== */

.gear-list{

    margin-top:20px;

}


.gear-item{

    padding:12px;

    margin-bottom:8px;

    background:#f1f7ff;

    border:1px solid #cbd8e8;

    border-radius:6px;

    cursor:pointer;

    font-weight:bold;

}


.gear-item:hover{

    background:#dcecff;

}


/* ===========================
   MODAL OVERLAY
=========================== */

.gear-modal-overlay{

    display:none;

    position:fixed;

    inset:0;

    background:rgba(0,0,0,.45);

    align-items:center;

    justify-content:center;

    z-index:2000;

}


.gear-modal-overlay.active{

    display:flex;

}


/* ===========================
   MODAL
=========================== */

.gear-modal{

    width:380px;

    max-width:90%;

    max-height:90vh;

    overflow-y:auto;

    background:white;

    padding:25px;

    border-radius:12px;

    box-shadow:0 10px 35px rgba(0,0,0,.3);

}


.gear-modal h2{

    font-family:'Orbitron',sans-serif;

    color:#012043;

    text-align:center;

    margin-bottom:20px;

}


.gear-modal label{

    display:block;

    margin-top:12px;

    margin-bottom:5px;

    font-weight:bold;

}


.gear-modal input{

    width:100%;

    padding:10px;

    border:1px solid #aaa;

    border-radius:6px;

    font-size:1rem;

}


.modal-buttons{

    display:flex;

    gap:10px;

    margin-top:25px;

}


.modal-buttons button{

    flex:1;

    padding:11px;

    border:none;

    border-radius:6px;

    cursor:pointer;

    font-size:1rem;

}

#deleteGear{

    background:#dc3545;

    color:white;

    display:none;

}


#deleteGear:hover{

    background:#b02a37;
}




#cancelGear{

    background:#ddd;

}


#generateGear{

    background:#0057d9;

    color:white;

}


#generateGear:hover{

    background:#003db8;

}

#gearPressureAngle:disabled{

    background:#e0e0e0;

    color:#777;

    cursor:not-allowed;

    border:1px solid #aaa;

}

/* ===========================
   CANVAS AREA
=========================== */

.canvas-area{

    flex:1;

    position:relative;

    min-width:0;

    min-height: 0;

    height: 100%;

    overflow:hidden;

}


#simulationCanvas{

    display:block;

    width:100%;

    height:100%;

    background:#def7ff;

    cursor: grab;

}

/* ===========================
   SIMULATOR LAYOUT - MOBILE
=========================== */

@media (max-width:768px){

    .simulator-layout{
        grid-template-columns:1fr;
        grid-template-rows:auto 1fr;
        height:auto;
        min-height:calc(100vh - 70px);
        overflow:visible;
    }

    .control-panel{
        height:auto;
        max-height:60vh;
        border-right:none;
        border-bottom:1px solid rgba(0,0,0,.15);
        box-shadow:0 2px 8px rgba(0,0,0,.08);
    }

    .canvas-area{
        height:60vh;
        min-height:300px;
    }

    .parameter-row{
        flex-wrap:wrap;
    }

    .parameter-row label{
        width:100%;
        margin-bottom:4px;
    }

    .parameter-row input,
    .parameter-row select{
        width:100%;
    }
}

#simulationCanvas{
    touch-action:none;
}