/* --- VARIABLES (System Theme) --- */
:root {
    --primary: #0056b3;
    --primary-dark: #004494;
    --bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    --card-bg: rgba(255, 255, 255, 0.9);
    --text-main: #333;
    --text-light: #666;
    --input-bg: #f9f9f9;
    --border: #e1e1e1;
    --shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);
    --error: #e74c3c;
}

@media (prefers-color-scheme: dark) {
    :root {
        --primary: #339af0;
        --primary-dark: #1c7ed6;
        --bg-gradient: linear-gradient(135deg, #0f2027 0%, #203a43 50%, #2c5364 100%);
        --card-bg: rgba(30, 30, 30, 0.85);
        --text-main: #fff;
        --text-light: #aaa;
        --input-bg: #2a2a2a;
        --border: #444;
        --shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.5);
    }
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', sans-serif;
}

body {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-gradient);
    background-size: cover;
    padding: 20px;
    /* Padding added for mobile scroll */
}

/* Back Button */
.back-home {
    position: absolute;
    top: 20px;
    left: 20px;
    color: var(--text-main);
    font-weight: 600;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 15px;
    background: var(--card-bg);
    border-radius: 30px;
    -webkit-backdrop-filter: blur(5px);
    backdrop-filter: blur(5px);
    transition: 0.3s;
    z-index: 10;
}

.back-home:hover {
    transform: translateX(-5px);
    color: var(--primary);
}

/* Card */
.reg-card {
    width: 100%;
    max-width: 450px;
    background: var(--card-bg);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 20px;
    padding: 30px;
    box-shadow: var(--shadow);
    animation: zoomIn 0.5s ease;
}

.brand-header {
    text-align: center;
    margin-bottom: 25px;
}

.brand-header h2 {
    color: var(--text-main);
    font-size: 1.8rem;
}

.brand-header p {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* Inputs */
.input-group {
    position: relative;
    margin-bottom: 20px;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 12px 40px 12px 45px;
    background: var(--input-bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text-main);
    font-size: 1rem;
    outline: none;
    transition: 0.3s;
    appearance: none;
    /* Removes default arrow */
}

/* Specific styling for Select Dropdown */
.select-group select {
    color: var(--text-main);
}

.select-group select:invalid {
    color: var(--text-light);
}

.arrow-icon {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
    pointer-events: none;
    font-size: 0.8rem;
}

/* Floating Labels */
.input-group label {
    position: absolute;
    left: 45px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
    pointer-events: none;
    transition: 0.3s;
    font-size: 0.95rem;
}

.input-group input:focus,
.input-group select:focus {
    border-color: var(--primary);
    background: transparent;
}

/* Label Movement Logic */
.input-group input:focus~label,
.input-group input:not(:placeholder-shown)~label {
    top: 0px;
    left: 15px;
    font-size: 0.75rem;
    padding: 0 5px;
    background: var(--card-bg);
    color: var(--primary);
}

.input-icon {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
}

/* Two columns for Password */
.row {
    display: flex;
    gap: 15px;
}

.row .input-group {
    flex: 1;
}

/* Buttons */
.btn-register {
    width: 100%;
    padding: 14px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-top: 10px;
}

.btn-register:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* Links */
.login-prompt {
    text-align: center;
    margin-top: 20px;
    font-size: 0.9rem;
    color: var(--text-light);
}

.login-prompt a {
    color: var(--primary);
    font-weight: bold;
    text-decoration: none;
}

.error-text {
    color: var(--error);
    font-size: 0.85rem;
    text-align: center;
    margin-bottom: 10px;
    min-height: 20px;
}

/* Animations */
@keyframes zoomIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Responsive */
@media (max-width: 480px) {
    .row {
        flex-direction: column;
        gap: 0;
    }
}