@import url('https://fonts.googleapis.com/css2?family=Montserrat:ital,wght@0,100..900;1,100..900&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Allan:wght@400;700&display=swap');
@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:ital,wght@0,100..700;1,100..700&display=swap');
:root {
    --primary-color: #4A4A4A;
    --secondary-color: #3E3E3E;
    --accent-color: #333333;

    --background-color: #131313;

    --white-light: #F5F5F5;
    --white: #FFFFFF;
    --white-dark: #E0E0E0;

    --grey-light: #171627;
    --grey-medium: #130f20;
    --grey-dark: #090813;
    --grey-dark-btn: #0D1127;
    --grey-dark-border: #0F1C53;

}

.text-white{
    color: var(--white-light);
}
.text-grey{
    color: var(--white-dark);
}

html, body {
    margin: 0;
    padding: 0;
    overflow-x: hidden;
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: url('../images/back2.jpeg') no-repeat center center;
    background-size: cover;
    /*font-family: "Montserrat", sans-serif;*/
    font-optical-sizing: auto;
    font-style: normal;
    font-family: "IBM Plex Sans", sans-serif;
}

main {
    flex-grow: 1;
}

.container-fluid {
    padding-left: 0 !important;
    padding-right: 0 !important;
}
.navbar.header {
    background: rgba(0, 128, 0, 0.25); /* smooth transparent green */
    backdrop-filter: blur(6px); /* glass effect */
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.header .nav-item a {
    text-decoration: none !important;
    color: var(--white-light);
    font-weight: bolder;
    padding: 8px 15px; /* Add padding for better border spacing */
    border-radius: 5px; /* Smooth corners for border */
    transition: 
        color 0.3s ease, 
        border-color 0.3s ease, 
        box-shadow 0.5s ease;
    border: 2px solid transparent; /* Reserve space for border */
    display: inline-block; /* To make padding and border work nicely */
    background-color: rgba(255, 255, 255, 0.1); /* light bg for contrast */
}

/* Hover effect: dotted border with glowing fade */
.header .nav-item a:hover {
    border-style: dotted;
    border-color: var(--accent-color, #00bfff); /* Replace with your glow color */
    color: var(--white); /* Slight color change on hover */

    /* Glow effect using box-shadow */
    box-shadow:
        0 0 8px 2px rgba(0, 191, 255, 0.6), /* bright glow */
        0 0 15px 6px rgba(0, 191, 255, 0.3); /* fading outer glow */
}

/* Active tab style, keep strong but match new glow */
.header .nav-item .active {
    color: var(--white-light);
    /* background-color: var(--grey-dark-btn); */
    box-shadow: inset 0 0 4px rgba(0, 0, 0, 0.05), 0 2px 6px rgba(0, 0, 0, 0.08);
    border: none;
    outline: none;
    transition: box-shadow 0.3s ease;
       background-color: rgba(0, 128, 0, 0.65); /* solid green highlight */
}

/* Optional: subtle glow on active as well */
.header .nav-item .active:hover {
    box-shadow:
        inset 0 0 4px rgba(0, 0, 0, 0.05), 
        0 0 8px 2px rgba(0, 191, 255, 0.6);
}


.button {
    background-color: var(--background-color);
    border: none;
    color: white;
    padding: 10px 20px;
    cursor: pointer;
    text-align: center;
}


.card-primary {
    background-color: var(--grey-medium) !important;
}

.card-secondary {
    background: url('../images/back2.jpeg') no-repeat center center;
}

.card-third {
    background-color: var(--accent-color) !important;
    color: var(--white-light);
}

.card-fourth {
    color: var(--white-light);
    background-color: var(--background-color) !important;
}

.col {
    min-width: 288px;
    margin: 16px
}

.flip-card-container {
    width: 100%;
    height: 200px;
}

.flip-card-inner {
    width: 100%;
    height: 100%;
    transition: transform 0.1s ease-in-out;
    transform-style: preserve-3d;
    position: relative;
}

.flip-card-side {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 1rem;
    padding: 1.5rem;
    text-align: center;
    background: linear-gradient(135deg, var(--grey-dark), var(--grey-light));
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
    color: var(--white-light);
    border: 0.5px solid var(--primary-color);
}

.front {
    z-index: 2;
}
.flip-card-side:hover {
    background: linear-gradient(135deg, var(--grey-dark-border), var(--grey-dark));
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
    color: var(--white-light);
    border: 1px dotted var(--white-light);
}

.flip-card-side.back {
    transform: rotateY(180deg);
}

.cursor-pointer {
    cursor: pointer;
}


.project-card img {
    max-width: 192px;
    max-height: 192px;
}


.voltage-button {
    position:relative;
    button {
        color:white;
        background: #0D1127;
        padding: 0.4rem 1.25rem 0.5rem 1.25rem;
        border-radius:5rem;
        border: 3px solid var(--grey-dark-border);
        font-size:0.8rem;
        line-height:1em;
        letter-spacing:0.075em;
        transition:background 0.3s;
        &:hover {
            cursor:pointer;
            + svg, +svg + .dots {
                opacity:1;
            }
        }
    }
    svg {
        display:block;
        position:absolute;
        top:-0.75em;
        left:-0.25em;
        width: calc(100% + 0.2em);
        height: calc(100% + 0.5em);
        pointer-events:none;
        opacity:0;
        transition:opacity 0.4s;
        transition-delay:0.1s;
        path {
            stroke-dasharray: 100;
            filter: url('#glow');
            &.line-1 {
                stroke:#f6de8d;
                stroke-dashoffset: 0;
                animation: spark-1 3s linear infinite;
            }
            &.line-2 {
                stroke:#6bfeff;
                stroke-dashoffset: 500;
                animation: spark-2 3s linear infinite;
            }
        }
    }
    .dots {
        opacity:0;
        transition:opacity 0.3s;
        transition-delay:0.4s;
        .dot {
            width:1rem;
            height:1rem;
            background:white;
            border-radius:100%;
            position:absolute;
            opacity:0;
        }
        .dot-1 {
            top:0;
            left:20%;
            animation: fly-up 3s linear infinite;
        }
        .dot-2 {
            top:0;
            left:55%;
            animation: fly-up 3s linear infinite;
            animation-delay: 0.5s;
        }
        .dot-3 {
            top:0;
            left:80%;
            animation: fly-up 3s linear infinite;
            animation-delay: 1s;
        }
        .dot-4 {
            bottom:0;
            left:30%;
            animation: fly-down 3s linear infinite;
            animation-delay: 2.5s;
        }
        .dot-5 {
            bottom:0;
            left:65%;
            animation: fly-down 3s linear infinite;
            animation-delay: 1.5s;
        }
    }
}


/* Container padding */
#login .container {
    max-width: 420px; /* Limit width for a neat form */
    background: linear-gradient(135deg, var(--grey-dark), var(--grey-light));
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.25);
    padding: 40px 30px;
}

/* Label style */
#login label.form-label {
    background-color: var(--accent-color, #007bff);
    color: #fff;
    font-weight: 600;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0, 123, 255, 0.4);
    user-select: none;
}

/* Input fields */
#login input.input-field {
    border: 2px solid var(--grey-dark-btn, #444);
    border-radius: 8px;
    padding: 12px 15px;
    font-size: 1rem;
    background-color: var(--grey-darker-bg, #1e1e1e);
    color: var(--white-light, #eee);
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    box-shadow: inset 0 2px 5px rgba(0, 0, 0, 0.4);
}

/* Input focus effect */
#login input.input-field:focus {
    border-color: var(--accent-color, #007bff);
    box-shadow: 0 0 8px 2px rgba(0, 123, 255, 0.6);
    outline: none;
}

/* Login button */
#login button.login-button {
    background: linear-gradient(135deg, #00bfff, #007bff);
    border: none;
    color: white;
    font-weight: 700;
    padding: 14px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 4px 10px rgba(0, 123, 255, 0.5);
}

/* Button hover effect */
#login button.login-button:hover {
    background: linear-gradient(135deg, #007bff, #00bfff);
    box-shadow: 0 6px 18px rgba(0, 191, 255, 0.8);
}

/* Button active effect */
#login button.login-button:active {
    background: linear-gradient(135deg, #005bbb, #004f99);
    box-shadow: none;
    transform: scale(0.98);
}

/* Responsive tweaks */
@media (max-width: 576px) {
    #login .container {
        padding: 30px 20px;
    }
}


/* Contact form container: light card with shadow and rounded corners */
#contact .container {
  max-width: 500px;
  background: linear-gradient(135deg, var(--grey-dark), var(--grey-light));
  padding: 40px 30px;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(0, 123, 255, 0.15);
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Form labels: subtle pastel blue with letter spacing */
#contact label.form-label {
  display: block;
  font-weight: 600;
  color: var(--white-light); /* deep blue */
  margin-bottom: 8px;
  letter-spacing: 0.04em;
}

/* Input and textarea styling */
#contact input.form-control,
#contact textarea.form-control {
  border: 2px solid #a8c0ff;
  border-radius: 10px;
  padding: 12px 15px;
  font-size: 1rem;
  background-color: var(--white-dark);
  color: #222;
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.05);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
  resize: none; /* no resizing for textarea */
}

/* Input and textarea focus glow effect */
#contact input.form-control:focus,
#contact textarea.form-control:focus {
  border-color: #4a90e2;
  box-shadow: 0 0 14px 3px rgba(74, 144, 226, 0.5);
  outline: none;
}

/* Placeholder color for inputs */
#contact input.form-control::placeholder,
#contact textarea.form-control::placeholder {
  color: var(--white-light);
  font-style: italic;
}

/* Submit button with gradient and glow */
#contact button.contact-submit {
  background: linear-gradient(135deg, #4a90e2, #357abd);
  border: none;
  color: var(--primary-color);
  font-weight: 700;
  padding: 14px 0;
  font-size: 1.15rem;
  cursor: pointer;
  border-radius: 10px;
  box-shadow: 0 5px 15px rgba(53, 122, 189, 0.6);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

/* Hover and active states for button */
#contact button.contact-submit:hover {
  background: linear-gradient(135deg, #357abd, #4a90e2);
  box-shadow: 0 7px 20px rgba(74, 144, 226, 0.8);
}
#contact button.contact-submit:active {
  background: linear-gradient(135deg, #2a5e9f, #285688);
  box-shadow: none;
  transform: scale(0.98);
}


.spin-card img {
    transition: transform 0.6s ease-in-out;
}

.spin-card:hover img {
    transform: rotate(360deg);
}

.custom-btn {
    background: linear-gradient(135deg, #007bff, #6610f2);
    color: #fff;
    border: none;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    letter-spacing: 0.5px;
    border-radius: 50px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.custom-btn:hover {
    background: linear-gradient(135deg, #6610f2, #007bff);
    transform: translateY(-2px);
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.15);
    color: #fff;
    text-decoration: none;
}



/* Responsive padding */
@media (max-width: 576px) {
  #contact .container {
    padding: 30px 20px;
  }
}


@keyframes spark-1 {
    to {
        stroke-dashoffset: -1000;
    }
}
@keyframes spark-2 {
    to {
        stroke-dashoffset: -500;
    }
}
@keyframes fly-up{
    0% { opacity:0; transform:translateY(0) scale(0.2); }
    5% { opacity:1; transform:translateY(-1.5rem) scale(0.4);}
    10%,100%{ opacity:0;  transform:translateY(-3rem) scale(0.2);}
}
@keyframes fly-down {
    0% { opacity:0; transform:translateY(0) scale(0.2); }
    5% { opacity:1; transform:translateY(1.5rem) scale(0.4);}
    10%,100%{ opacity:0;  transform:translateY(3rem) scale(0.2);}
}