:root {
            --icy-bg: #090b10;
            --icy-panel: rgba(255,255,255,.08);
            --icy-panel-strong: rgba(255,255,255,.13);
            --icy-line: rgba(255,255,255,.14);
            --icy-text: #f7fbff;
            --icy-soft: #aeb9c8;
            --icy-orange: #ff6a00;
            --icy-cyan: #35e0d1;
            --icy-lime: #b8f56d;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            min-height: 100vh;
            display: flex;
            overflow-x: hidden;
            background:
                radial-gradient(circle at 16% 0, rgba(53,224,209,.18), transparent 34%),
                radial-gradient(circle at 88% 8%, rgba(255,106,0,.16), transparent 30%),
                linear-gradient(180deg, #0d1017 0%, var(--icy-bg) 100%);
            color: var(--icy-text);
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
        }
        .left-section {
            position: relative;
            width: 48%;
            min-height: 100vh;
            overflow: hidden;
            background:
                linear-gradient(135deg, rgba(9,11,16,.46), rgba(9,11,16,.18) 48%, rgba(255,106,0,.24)),
                url('../image/login_bg.webp');
            background-size: cover;
            background-position: center;
            background-repeat: no-repeat;
        }
       
       
        .auth-back-btn {
            position: fixed;
            top: max(18px, env(safe-area-inset-top));
            left: max(18px, env(safe-area-inset-left));
            z-index: 20;
            width: 42px;
            height: 42px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            border: 1px solid rgba(255,255,255,.16);
            border-radius: 8px;
            background:
                linear-gradient(145deg, rgba(255,255,255,.12), rgba(255,255,255,.04)),
                rgba(8,11,18,.72);
            color: #dff9ff;
            cursor: pointer;
            box-shadow: 0 18px 42px rgba(0,0,0,.34), inset 0 1px 0 rgba(255,255,255,.07);
            backdrop-filter: blur(18px);
            transition: transform .18s ease, border-color .18s ease, background .18s ease;
        }
        .auth-back-btn:hover {
            transform: translateY(-1px);
            border-color: rgba(53,224,209,.62);
            background:
                linear-gradient(145deg, rgba(53,224,209,.20), rgba(255,106,0,.10)),
                rgba(8,11,18,.86);
        }
        .auth-back-btn svg {
            width: 20px;
            height: 20px;
            stroke: currentColor;
            stroke-width: 2.4;
            fill: none;
            stroke-linecap: round;
            stroke-linejoin: round;
        }
        .right-section {
            width: 52%;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            justify-content: center;
            padding: 34px 50px;
            max-width: 560px;
            margin: 0 auto;
            gap: 18px;
        }
        .right-section h2 {
            color: #fff;
            font-size: clamp(28px, 3vw, 40px);
            line-height: 1.1;
            font-weight: 900;
            letter-spacing: 0;
            text-shadow: 0 18px 42px rgba(0,0,0,.36);
        }
        .right-section h2::before {
            content: "WTCBUY";
            display: block;
            margin-bottom: 7px;
            color: var(--icy-cyan);
            font-size: 12px;
            font-weight: 900;
            letter-spacing: .14em;
        }
        .right-section h2::after {
            content: attr(data-i18n-content);
            display: block;
            margin-top: 9px;
            max-width: 430px;
            color: var(--icy-soft);
            font-size: 13px;
            line-height: 1.45;
            font-weight: 700;
            text-shadow: none;
        }
        .input-group {
            width: 100%;
            display: flex;
            flex-direction: column;
            gap: 12px;
            padding: 20px;
            border: 1px solid var(--icy-line);
            border-radius: 10px;
            background:
                radial-gradient(circle at 18% 0, rgba(53,224,209,.12), transparent 34%),
                radial-gradient(circle at 86% 90%, rgba(255,106,0,.12), transparent 34%),
                rgba(255,255,255,.07);
            box-shadow: 0 28px 80px rgba(0,0,0,.36), inset 0 1px 0 rgba(255,255,255,.07);
            backdrop-filter: blur(18px);
        }
        .input-wrapper,
        .password-wrapper {
            position: relative;
            width: 100%;
        }
        .input-group input {
            width: 100%;
            min-height: 48px;
            padding: 13px 15px;
            border: 1px solid rgba(255,255,255,.13);
            background: rgba(8,11,18,.62);
            border-radius: 6px;
            color: var(--icy-text);
            font-size: 14px;
            outline: none;
            box-shadow: inset 0 1px 0 rgba(255,255,255,.05);
            transition: border-color .18s ease, background .18s ease, box-shadow .18s ease;
        }
        .input-group input::placeholder {
            color: rgba(174,185,200,.76);
        }
        .password-wrapper input {
            padding-right: 70px;
        }
        .input-group input:focus {
            border-color: rgba(53,224,209,.62);
            background: rgba(8,11,18,.82);
            box-shadow: 0 0 0 3px rgba(53,224,209,.12), inset 0 1px 0 rgba(255,255,255,.06);
        }
        .toggle-password {
            position: absolute;
            right: 14px;
            top: 50%;
            transform: translateY(-50%);
            cursor: pointer;
            font-size: 18px;
            font-weight: 900;
            line-height: 1;
            color: var(--icy-soft);
            user-select: none;
            background: transparent;
            border: none;
            padding: 0;
            transition: color .18s ease;
        }
        .toggle-password:hover {
            color: var(--icy-cyan);
        }
        .password-hint {
            display: grid;
            gap: 5px;
            padding: 12px 13px;
            border: 1px solid rgba(255,255,255,.10);
            border-left: 3px solid var(--icy-cyan);
            border-radius: 8px;
            background: rgba(8,11,18,.42);
            color: var(--icy-soft);
            font-size: 12px;
        }
        .password-hint-title {
            margin-bottom: 2px;
            color: #fff;
            font-size: 12px;
            font-weight: 900;
        }
        .hint-item {
            display: flex;
            align-items: center;
            gap: 8px;
            color: var(--icy-soft);
            font-size: 11px;
            line-height: 1.35;
        }
        .hint-item .check-icon {
            width: 16px;
            text-align: center;
            color: rgba(174,185,200,.72);
        }
        .hint-item.valid,
        .hint-item.valid .check-icon {
            color: var(--icy-lime);
        }
        .hint-item.invalid {
            color: rgba(174,185,200,.72);
        }
        .code-group {
            display: grid;
            grid-template-columns: minmax(0, 1fr) 126px;
            gap: 10px;
        }
        .code-group button {
            min-height: 48px;
            padding: 0 12px;
            border: 1px solid rgba(53,224,209,.46);
            border-radius: 6px;
            background: rgba(53,224,209,.12);
            color: #dff9ff;
            font-size: 13px;
            font-weight: 900;
            cursor: pointer;
            white-space: nowrap;
            transition: background .18s ease, border-color .18s ease, transform .18s ease;
        }
        .code-group button:hover:not(:disabled) {
            border-color: rgba(53,224,209,.74);
            background: rgba(53,224,209,.18);
            transform: translateY(-1px);
        }
        .code-group button:disabled {
            background: rgba(174,185,200,.20);
            border-color: rgba(174,185,200,.18);
            color: rgba(247,251,255,.58);
            cursor: not-allowed;
            transform: none;
        }
        .agree-box {
            display: grid;
            grid-template-columns: 18px 1fr;
            gap: 9px;
            color: var(--icy-soft);
            font-size: 12px;
            line-height: 1.45;
        }
        .agree-box input[type="checkbox"] {
            width: 16px;
            height: 16px;
            min-height: 0;
            margin-top: 2px;
            accent-color: var(--icy-orange);
        }
        .agree-box a,
        .bottom-login a {
            color: var(--icy-cyan);
            text-decoration: none;
            font-weight: 800;
        }
        .agree-box a:hover,
        .bottom-login a:hover {
            color: var(--icy-orange);
        }
        .signup-btn {
            width: 100%;
            min-height: 52px;
            padding: 14px 16px;
            background: linear-gradient(135deg, #ff7a12, var(--icy-orange));
            color: #fff;
            border: none;
            border-radius: 6px;
            font-size: 16px;
            font-weight: 900;
            cursor: pointer;
            box-shadow: 0 16px 38px rgba(255,106,0,.24), inset 0 1px 0 rgba(255,255,255,.22);
            transition: transform .18s ease, box-shadow .18s ease, filter .18s ease;
        }
        .signup-btn:hover {
            transform: translateY(-1px);
            filter: brightness(1.04);
            box-shadow: 0 20px 46px rgba(255,106,0,.30), inset 0 1px 0 rgba(255,255,255,.24);
        }
        .signup-btn:disabled {
            background: rgba(174,185,200,.28);
            box-shadow: none;
            cursor: not-allowed;
            transform: none;
        }
        .bottom-login {
            width: 100%;
            text-align: center;
            color: var(--icy-soft);
            font-size: 13px;
            font-weight: 700;
        }
        .modal {
            display: none;
            position: fixed;
            inset: 0;
            width: 100%;
            height: 100%;
            padding: 18px;
            background: rgba(0,0,0,.62);
            z-index: 1000;
            justify-content: center;
            align-items: center;
            backdrop-filter: blur(10px);
        }
        .modal-content {
            width: min(360px, 100%);
            background:
                radial-gradient(circle at 18% 0, rgba(53,224,209,.13), transparent 36%),
                rgba(13,16,23,.96);
            border: 1px solid var(--icy-line);
            padding: 28px 26px;
            border-radius: 8px;
            text-align: center;
            box-shadow: 0 28px 90px rgba(0,0,0,.48), inset 0 1px 0 rgba(255,255,255,.08);
            color: var(--icy-text);
        }
        .modal-content .success-icon {
            color: var(--icy-cyan);
            font-size: 50px;
            margin-bottom: 15px;
        }
        .modal-content .error-icon {
            color: var(--icy-orange);
            font-size: 50px;
            margin-bottom: 15px;
        }
        .modal-content h3 {
            margin-bottom: 10px;
            font-size: 20px;
        }
        .modal-content p {
            margin-bottom: 20px;
            color: var(--icy-soft);
        }
        .modal-content button {
            min-width: 110px;
            padding: 10px 26px;
            background: linear-gradient(135deg, #ff7a12, var(--icy-orange));
            color: #fff;
            border: none;
            border-radius: 4px;
            cursor: pointer;
            font-size: 14px;
            font-weight: 900;
        }
        .modal-content button:hover {
            filter: brightness(1.04);
        }
        #confirmHint {
            min-height: 16px;
            font-size: 12px !important;
            margin-top: -4px !important;
            color: var(--icy-soft) !important;
            font-weight: 800;
        }